| Page 1 of 2 | 1 | 2 |
|
|
Wireless 802.11 NMEA server
I just want to say a big thanks to everyone on this group who
responded to my post last year regarding a wireless NMEA navigation server. Based on your ideas and suggestions we've turned it into a real product and are currently beta testing it with a number of boats: http://www.marinewireless.us Anyhow, thanks again for all the feedback and help in turning this idea into reality. Now we'll just have to see if there is any real market demand for wireless navigation ;-) -Todd |
Wireless 802.11 NMEA server
Todd, I'm using the B&B Electronics serial direct to network box
between our NMEA network and a $39 Netgear wireless router. The box is $149, not $700 West Marine pricing. Are you using their Virtual Serial Port software? It works great with The Cap'n, totally transparent. The Cap'n thinks it's talking to the serial port, not the TCP/IP of the Linksys PCMCIA card in the side of the Dell Latitude. Pretty cool to sit on the bow and waypoint the B&G Network Pilot....(c; I can also simultaneously logon to Ashley Marina's WiFi open network near the docks very nicely. Too bad noone has a better WiFi network out in the harbor....dammit. The RS-232 I/O works very nicely with our Noland Multiplexer's RX/TX port. The Cap'n gets the data and waypoints her around great! B&B Electronics specializes in remote instrumentation...... On 6 Nov 2003 11:20:57 -0800, (Todd) wrote: I just want to say a big thanks to everyone on this group who responded to my post last year regarding a wireless NMEA navigation server. Based on your ideas and suggestions we've turned it into a real product and are currently beta testing it with a number of boats: http://www.marinewireless.us Anyhow, thanks again for all the feedback and help in turning this idea into reality. Now we'll just have to see if there is any real market demand for wireless navigation ;-) -Todd Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Todd" wrote in message
... I just want to say a big thanks to everyone on this group who responded to my post last year regarding a wireless NMEA navigation server. Based on your ideas and suggestions we've turned it into a real product and are currently beta testing it with a number of boats: http://www.marinewireless.us Nice piece of marketing. Take an off-the-shelf product (Soekris Engineering net4521 , ~ $200 including case), put your own label on it, load it with linux and sell it for 4 times the price of the off-the-shelf product... Pity though that this NMEA navigation server has no real NMEA inputs/outputs. :-) Meindert |
Wireless 802.11 NMEA server
Is it just me or is rec.boats.electronics becoming a playground for
the SPAMMERS? On Fri, 7 Nov 2003 08:29:33 +0100, "Meindert Sprang" wrote: "Todd" wrote in message m... I just want to say a big thanks to everyone on this group who responded to my post last year regarding a wireless NMEA navigation server. Based on your ideas and suggestions we've turned it into a real product and are currently beta testing it with a number of boats: http://www.marinewireless.us Nice piece of marketing. Take an off-the-shelf product (Soekris Engineering net4521 , ~ $200 including case), put your own label on it, load it with linux and sell it for 4 times the price of the off-the-shelf product... Pity though that this NMEA navigation server has no real NMEA inputs/outputs. :-) Meindert Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... Is it just me or is rec.boats.electronics becoming a playground for the SPAMMERS? Who gave you that idea?? :-)) Meindert |
Wireless 802.11 NMEA server
"Meindert Sprang" wrote in message
Nice piece of marketing. Take an off-the-shelf product (Soekris Engineering net4521 , ~ $200 including case), put your own label on it, load it with linux and sell it for 4 times the price of the off-the-shelf product... Pity though that this NMEA navigation server has no real NMEA inputs/outputs. :-) Meindert Meindart, Indeed, the soekris is a great unit and embedded linux was a natural choice. Our thinking regarding no real NMEA inputs/outputs was that we want to support seatalk networks, seatalk/nmea networks, and straight nmea so going with an external multiplexer (e.g. Noland, Brookhouse, Raymarine NMEA bride, etc...) makes a lot more sense and quite frankly is a lot easier at this early stage. I would eventually like to integrate something like the Brookhouse unit which does both NMEA and Seatalk and ultimately get the cost down more but that only happens when you can start buying in some significant volume. I think you're oversimplifying regarding $200 for the soekris since that's only a part of the equation. There's also 200mW senoa wireless card, external antenna, internal storage, 12 volt connection wiring, virtual serial port software, nmea navigation embedded server software, a web based administration interface, etc... We're making nowhere near the 4 times profit you suggest on this unit so it's not as nice a piece of marketing as you give me credit for, although I wish it were ;-) Thanks for your feedback, it really is a big help to see which areas folks are critical of so I can work on sorting those out for when we begin actually selling the product to end users! Cheers, Todd -- Marine Wireless http://www.marinewireless.us |
Wireless 802.11 NMEA server
Larry,
I didn't know about the B&B unit, thanks for pointing it out! I'm glad to see other folks are doing wireless navigation on their boats. Does the B&B unit support multiple clients (e.g. multiple laptops and handhelds) getting the NMEA data at the same time? Do you have the netgear and B&B running through the inverter or were you able to wire them both into the 12V power? It sounds like a good and inexpensive solution! That's the downside of making a product specific for the marine industry... low volume = higher pricing. Cheers, Todd -- Marine Wireless http://www.marinewireless.us (Larry W4CSC) wrote in message ... Todd, I'm using the B&B Electronics serial direct to network box between our NMEA network and a $39 Netgear wireless router. The box is $149, not $700 West Marine pricing. Are you using their Virtual Serial Port software? It works great with The Cap'n, totally transparent. The Cap'n thinks it's talking to the serial port, not the TCP/IP of the Linksys PCMCIA card in the side of the Dell Latitude. Pretty cool to sit on the bow and waypoint the B&G Network Pilot....(c; I can also simultaneously logon to Ashley Marina's WiFi open network near the docks very nicely. Too bad noone has a better WiFi network out in the harbor....dammit. The RS-232 I/O works very nicely with our Noland Multiplexer's RX/TX port. The Cap'n gets the data and waypoints her around great! B&B Electronics specializes in remote instrumentation...... On 6 Nov 2003 11:20:57 -0800, (Todd) wrote: I just want to say a big thanks to everyone on this group who responded to my post last year regarding a wireless NMEA navigation server. Based on your ideas and suggestions we've turned it into a real product and are currently beta testing it with a number of boats: http://www.marinewireless.us Anyhow, thanks again for all the feedback and help in turning this idea into reality. Now we'll just have to see if there is any real market demand for wireless navigation ;-) -Todd Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Todd" wrote in message Meindart,
Indeed, the soekris is a great unit and embedded linux was a natural choice. And a good one too! Glad you didn't opt for a M$ product ;-) Our thinking regarding no real NMEA inputs/outputs was that we want to support seatalk networks, seatalk/nmea networks, and straight nmea so going with an external multiplexer (e.g. Noland, Brookhouse, Raymarine NMEA bride, etc...) makes a lot more sense and quite frankly is a lot easier at this early stage. I would eventually like to integrate something like the Brookhouse unit which does both NMEA and Seatalk and ultimately get the cost down more but that only happens when you can start buying in some significant volume. Mmm, might want to discuss this with you directly. I think you're oversimplifying regarding $200 for the soekris since that's only a part of the equation. There's also 200mW senoa wireless card, external antenna, internal storage, 12 volt connection wiring, virtual serial port software, nmea navigation embedded server software, a web based administration interface, etc... We're making nowhere near the 4 times profit you suggest on this unit so it's not as nice a piece of marketing as you give me credit for, although I wish it were ;-) Ok, I was a bit overreacting :-) Indeed it takes a lot of effort to make it a complete product. I remember when I had the first prototype of my multiplexers ready and how long it took before it was a sellable product. that took longer than to develop the first proto. Thanks for your feedback, it really is a big help to see which areas folks are critical of so I can work on sorting those out for when we begin actually selling the product to end users! You're welcome :-) Cheer, Meindert |
Wireless 802.11 NMEA server
|
Wireless 802.11 NMEA server
Why do I keep dreaming of an 802.11g network interface on every piece
of electronics NMEA connects by wires, now? Hell, with broadband, I could overlay the color radar display from the Raymarine right all the computer screens aboard! AND NO WIRES TO PULL THROUGH THE DAMNED BOAT!!.....(9C:) TCP/IP all around..... Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
How true. It has taken so long for NEMA2000 to get settled and will be
even longer before it gets implemented by a significant number of vendors that wires are going to be superfluous before it finds a market. Network instruments will be the last thing installed on Rutu before I add water. Larry W4CSC wrote: Why do I keep dreaming of an 802.11g network interface on every piece of electronics NMEA connects by wires, now? Hell, with broadband, I could overlay the color radar display from the Raymarine right all the computer screens aboard! AND NO WIRES TO PULL THROUGH THE DAMNED BOAT!!.....(9C:) TCP/IP all around..... Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... Why do I keep dreaming of an 802.11g network interface on every piece of electronics NMEA connects by wires, now? Hell, with broadband, I could overlay the color radar display from the Raymarine right all the computer screens aboard! Well, do "steel hull" or "aluminum hull" ring a bell? Apart from that, you have to bring power to the electronics anyway, so whats wrong with an extra pair for data? Meindert |
Wireless 802.11 NMEA server
On Sat, 8 Nov 2003 00:36:32 +0100, "Meindert Sprang"
wrote: "Larry W4CSC" wrote in message ... Why do I keep dreaming of an 802.11g network interface on every piece of electronics NMEA connects by wires, now? Hell, with broadband, I could overlay the color radar display from the Raymarine right all the computer screens aboard! Well, do "steel hull" or "aluminum hull" ring a bell? Apart from that, you have to bring power to the electronics anyway, so whats wrong with an extra pair for data? Meindert The DC power is already in every space I ever install an instrument. I don't have to pull a wire through the bilge or engine room or overhead to get it. It's already there, plenty of it. As for your comment about wireless in metal hulls, try running a 2400 Mhz WiFi in a steel hull. 2400 Mhz flows right through hatches and other openings over 3" wide. But most people, here, don't have, or more accurately, wouldn't have a metal hull. Your argument to defend your turf is moot. Networking on metal boats could simply be added to the DC circuitry, like the powerline routers are doing now....though they'd have to operate above 24 Mhz to keep interference with the HF radios down. We've fooled around with a powerline router system with wall brick terminals that have Ethernet jacks on them, from Netgear. Every AC jack on the dock becomes a wideband internet connection across the marina. Works great! That could be added to the existing AC or DC power lines in metal boats.....USING TCP/IP NETWORKING, not some idiotic, proprietary protocol designed to prevent you from hooking A company's equipment to B company's equipment....you know....like we have now. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
As a metal boat owner, I don't have a choice. The boat looks like a series
of Faraday cages, with metal watertight doors pulled down against very thin gaskets and all the thru bulkhead fittings of minimum size. There will be no 3" gaps; one of the advantages of metal is that you have a good chance of keeping fire and flood in one compartment if you're careful. Even if I had a choice, however, I'd probably stick with wire. A boat is not a house or office. Aside from alternators, we have a variety of sources of potential interference -- radios (150 watt sideband and 25 watt VHFs), radar, and so forth. 802.11 "should" ignore all of that. But "should" is a big word at sea. Although the 10baseT pairs could also act as antennas and could pick up RFI, my instinct is that it's a safer choice. As for using either the AC or DC lines, I have the same objection. And even in relatively small boats, the AC system is usually split bus (so you can plug in two 120V 30A lines to a dock), so you have to do some capacitive coupling. Of course in saying all of this, I do have the advantage that we're doing a major refit, and it's very easy to lay in an extra conduit for the network (actually it isn't even extra as we'll have a conduit for phone and signaling anyway). Certainly if I were adding a network to an existing boat that wasn't well set for easy access everywhere (that's another topic), I'd certainly take a shot at using wireless and test the hell out of it at the dock. -- Jim Woodward www.mvFintry.com .. "Larry W4CSC" wrote in message ... On Sat, 8 Nov 2003 00:36:32 +0100, "Meindert Sprang" wrote: "Larry W4CSC" wrote in message ... Why do I keep dreaming of an 802.11g network interface on every piece of electronics NMEA connects by wires, now? Hell, with broadband, I could overlay the color radar display from the Raymarine right all the computer screens aboard! Well, do "steel hull" or "aluminum hull" ring a bell? Apart from that, you have to bring power to the electronics anyway, so whats wrong with an extra pair for data? Meindert The DC power is already in every space I ever install an instrument. I don't have to pull a wire through the bilge or engine room or overhead to get it. It's already there, plenty of it. As for your comment about wireless in metal hulls, try running a 2400 Mhz WiFi in a steel hull. 2400 Mhz flows right through hatches and other openings over 3" wide. But most people, here, don't have, or more accurately, wouldn't have a metal hull. Your argument to defend your turf is moot. Networking on metal boats could simply be added to the DC circuitry, like the powerline routers are doing now....though they'd have to operate above 24 Mhz to keep interference with the HF radios down. We've fooled around with a powerline router system with wall brick terminals that have Ethernet jacks on them, from Netgear. Every AC jack on the dock becomes a wideband internet connection across the marina. Works great! That could be added to the existing AC or DC power lines in metal boats.....USING TCP/IP NETWORKING, not some idiotic, proprietary protocol designed to prevent you from hooking A company's equipment to B company's equipment....you know....like we have now. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
On Sat, 8 Nov 2003 09:09:57 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote: As a metal boat owner, I don't have a choice. The boat looks like a series of Faraday cages, with metal watertight doors pulled down against very thin gaskets and all the thru bulkhead fittings of minimum size. There will be no 3" gaps; one of the advantages of metal is that you have a good chance of keeping fire and flood in one compartment if you're careful. Sure wish I could get by your boat to test it out. Every wire going from compartment to compartment is a great antenna for 2400 Mhz....right through those watertight bulkheads. It would be interesting to see how far the usable signal got with the transmitter that close. Even if I had a choice, however, I'd probably stick with wire. A boat is not a house or office. Aside from alternators, we have a variety of sources of potential interference -- radios (150 watt sideband and 25 watt VHFs), radar, and so forth. 802.11 "should" ignore all of that. But "should" is a big word at sea. Although the 10baseT pairs could also act as antennas and could pick up RFI, my instinct is that it's a safer choice. The only 2400 Mhz RFI source on your boat is probably your microwave oven at 2450 Mhz. There is no interference from 150W of HF through the wireless.....LIKE THERE IS ON EVERY WIRE OF THE NMEA SYSTEM aboard the boat. NMEA wiring cannot be effectively shielded as long as manufacturers keep using hookup wire that's not shielded (Garmin) and even stupid Icom, itself, who made the M802 HF-SSB forces you to connect NMEA B (-) to the SHIELD OF A BNC CONNECTOR to hook NMEA input to the HF SSB with DSC. How stupid! Of course, NONE of the plastic boxes the damned cheap marine crap comes in is shielded in the first place against the HF transmitter or your 5W walkie talkie on deck. There's no FORCED standards, just NMEA suggestions from the NMEA the manufacturers control....sorta like the fox guarding the henhouse. As for using either the AC or DC lines, I have the same objection. And even in relatively small boats, the AC system is usually split bus (so you can plug in two 120V 30A lines to a dock), so you have to do some capacitive coupling. There's 2 primary transformers sitting on top of the floating dock at Ashley Marina. The powerline router signal coupled through them, to my amazement, good enough to get the WiFi through them. Of course in saying all of this, I do have the advantage that we're doing a major refit, and it's very easy to lay in an extra conduit for the network (actually it isn't even extra as we'll have a conduit for phone and signaling anyway). Certainly if I were adding a network to an existing boat that wasn't well set for easy access everywhere (that's another topic), I'd certainly take a shot at using wireless and test the hell out of it at the dock. On the larger boat, that's very nice. But, most boat manufacturers, in their attempts to maximize profits, don't put in even the most rudimentary conduit. The wires are just haphazardly laid in behind some panel squished between the panel and the fiberglass shards sticking out. The Endeavour was like that. The Amel Sharki is a different class. The overhead has conduit leading from the outside of the void between the cabin overhead and the deck into the void where there are wires to go in. There's plenty of space, but, alas, no way to fishtape from this little conduit nipple to the next. I finally made up a ring slider I could tie the fishtape to and slide it along the existing French wiring in the void to the other conduit nipple on the other end. It serves quite well. The void acts about 1 to 1.5" high over the main salon. Many wires go through there forward and aft. Do you have a strong high-channel-number UHF TV station in your area? Might be fun to play with a portable TV to see how far inside the boat its signal gets, but that's only 1/3 the network's frequency at 800 Mhz. Do cellular phones work inside? Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
(Larry W4CSC) wrote in message ...
Are you actually making this, or are you relabeling off-the-shelf stuff as someone says? Are you using this "Virtual Serial Port" software B&B is selling? Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" Hi Larry, Making versus relabling is a really grey issue when it comes to computer hardware. Just look at your wireless access point. They're using a CPU and board from one company, having the case manufactured by a different overseas company, and then using someone else's (probably prism based) 802.11 card and external antenna. Some access point manufacturers write their own firmware and others use linux (e.g. the Dell 802.11 access points). We're doing the same thing, very similar to Dell in that we have a domestic supplier we work with for the CPU and case, another vendor for the wireless transmitter, andenna, and solid state storage, linux as the embedded platform, and then our own embedded software on top of that. We currently do the assembly in-house. With regards to the virtual serial port software we currently use our own. With our beta program we will be evaluating our own virtual serial port software against another vendors and whichever comes out on top is what we will include with the final marine wireless navigation server. Best, Todd -- Marine Wireless http://www.marinewireless.us |
Wireless 802.11 NMEA server
"Jim Woodward" jameslwoodward at attbi dot com wrote in message ...
Certainly if I were adding a network to an existing boat that wasn't well set for easy access everywhere (that's another topic), I'd certainly take a shot at using wireless and test the hell out of it at the dock. -- Jim Woodward www.mvFintry.com Jim, I think you make a good point that testing is definitely the key before leaving the dock. Metal boats do present a problem for wireless networks and my take on doing wireless on a metal boat (assuming you want to and certainly not everyone does) is to mount the external antenna in the salon area so that any cabins (with non-metal or open doors) can access it and the signal can get up the companionway stairs to the cockpit. Would that give you a signal on the foredeck? As you say you'd just have to test it since it will vary with each boat. As an aside I would never recommend anyone use wireless as their sole means of electronic navigation. When we designed our wireless navigation server it was always as an addition to a set of fixed mounted instruments and even more importantly as an addition to having a paper chart and being able to navigate when you lose all form of power aboard. We also require an external NMEA multiplexer to combine the NMEA signals (or convert Seatalk) which allows you to unplug our wireless navigation server and plug the serial connection directly into a laptop were our hardware to fail. Best, Todd -- Marine Wireless http://www.marinewireless.us |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... The only 2400 Mhz RFI source on your boat is probably your microwave oven at 2450 Mhz. There is no interference from 150W of HF through the wireless.....LIKE THERE IS ON EVERY WIRE OF THE NMEA SYSTEM aboard the boat. NMEA wiring cannot be effectively shielded as long as..... You just take every opportunity for a rant about NMEA, don't you? Why would NMEA at 4800 baud produce more interference than a 100mbit network on UTP (U=Unshielded)? NONE of the plastic boxes the damned cheap marine crap comes in is shielded in the first place against the HF transmitter or your 5W walkie talkie on deck. Another one: It is NOT necessary to put electronics in a shielded boax to be EMC proof. It all depends on proper PCB layout. A lot of equipment in plastic unshielded boxes carry FCC or CE approval. They don't get that approval when the equipment is radiating like hell or going dead when keying an SSB. Meindert |
Wireless 802.11 NMEA server
What you describe is very typical. Very few of the high tech companies in
the Boston area actually "manufacture" in the sense that I knew it as a kid in Chicago. They never cut metal or paint it. They don't fab, stuff, solder or test PC boards. They just put things together that others make to spec. Recently even the putting together is offsite. As more and more of what's important in products like radars becomes the software, we'll see more products that differ only in software. My choice of Furuno for our big radar (I think, tune in later when I actually buy it) is based entirely on software and user interface. In truth, I haven't even looked at the antenna specs to see if there are any differences between Furuno, Raymarine, and Simrad. There's a fair amount of this in marine electronics. JRC made the Raytheon 41XX -- seems strange, as Raytheon is one of the premier radar companies in the world, but that's the way it was. Airmar makes most of the industry's depth sounder transducers. And so forth. -- Jim Woodward www.mvFintry.com .. "Todd" wrote in message m... (Larry W4CSC) wrote in message ... Are you actually making this, or are you relabeling off-the-shelf stuff as someone says? Are you using this "Virtual Serial Port" software B&B is selling? Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" Hi Larry, Making versus relabling is a really grey issue when it comes to computer hardware. Just look at your wireless access point. They're using a CPU and board from one company, having the case manufactured by a different overseas company, and then using someone else's (probably prism based) 802.11 card and external antenna. Some access point manufacturers write their own firmware and others use linux (e.g. the Dell 802.11 access points). We're doing the same thing, very similar to Dell in that we have a domestic supplier we work with for the CPU and case, another vendor for the wireless transmitter, andenna, and solid state storage, linux as the embedded platform, and then our own embedded software on top of that. We currently do the assembly in-house. With regards to the virtual serial port software we currently use our own. With our beta program we will be evaluating our own virtual serial port software against another vendors and whichever comes out on top is what we will include with the final marine wireless navigation server. Best, Todd -- Marine Wireless http://www.marinewireless.us |
Wireless 802.11 NMEA server
Larry and Todd:
It's not quite so simple -- take a look at http://www.mvfintry.com/pix/portland800.jpg. There are two w/t compartments on the main deck and six below, all possibly with data, as well as tanks. The wheelhouse can also be separated by a w/t door. (Remember that in The Perfect Storm movie, Andrea Gail flooded from the wheelhouse. What really happened, we'll never know.) Maybe you guys are right -- that wireless would work fine -- certainly there are a lot of openings in the bulkheads, although they're all small (2" tops) and sealed with intumescent caulk to keep fire and flood in one place if they happen -- AC, DC, H&C potable water, sal****er fire main, black and gray water, compressed air, diesel, and all the information wires. Question then, given that running wire is really easy, because we'll have the conduit for phone, burglar, fire alarm, audio, etc. anyway (sure, maybe all of these can be wireless also, but there are some security issues, etc.), am I better off with wired or wireless? If Larry's right and 802.11 will really reject everything that it might meet, is it a more robust installation to go wireless? This assumes that all of the primary stuff on the bridge is wired -- we're talking about personal computers (in the broader sense of the words) and a couple of non-critical remote readouts here. None of this will go in until we get her on this side of the pond next summer (God willing). I'd be delighted to try it sometime after then.... -- Jim Woodward www.mvFintry.com .. .. "Todd" wrote in message m... "Jim Woodward" jameslwoodward at attbi dot com wrote in message ... Certainly if I were adding a network to an existing boat that wasn't well set for easy access everywhere (that's another topic), I'd certainly take a shot at using wireless and test the hell out of it at the dock. -- Jim Woodward www.mvFintry.com Jim, I think you make a good point that testing is definitely the key before leaving the dock. Metal boats do present a problem for wireless networks and my take on doing wireless on a metal boat (assuming you want to and certainly not everyone does) is to mount the external antenna in the salon area so that any cabins (with non-metal or open doors) can access it and the signal can get up the companionway stairs to the cockpit. Would that give you a signal on the foredeck? As you say you'd just have to test it since it will vary with each boat. As an aside I would never recommend anyone use wireless as their sole means of electronic navigation. When we designed our wireless navigation server it was always as an addition to a set of fixed mounted instruments and even more importantly as an addition to having a paper chart and being able to navigate when you lose all form of power aboard. We also require an external NMEA multiplexer to combine the NMEA signals (or convert Seatalk) which allows you to unplug our wireless navigation server and plug the serial connection directly into a laptop were our hardware to fail. Best, Todd -- Marine Wireless http://www.marinewireless.us |
Wireless 802.11 NMEA server
On Sat, 8 Nov 2003 20:09:43 +0100, "Meindert Sprang"
wrote: "Larry W4CSC" wrote in message ... The only 2400 Mhz RFI source on your boat is probably your microwave oven at 2450 Mhz. There is no interference from 150W of HF through the wireless.....LIKE THERE IS ON EVERY WIRE OF THE NMEA SYSTEM aboard the boat. NMEA wiring cannot be effectively shielded as long as..... You just take every opportunity for a rant about NMEA, don't you? What rant? The truth is an unshielded RS-232 serial connection with ground hooked to one side of the damned balanced line is a big transmitter! Unshielded plastic crap has no business around an HF receiver with any kind of a switching IC inside it. Well....duhhhh.... I don't give a **** about your maximized profits in that plastic box. Why would NMEA at 4800 baud produce more interference than a 100mbit network on UTP (U=Unshielded)? Well, duhhh.....Lemme see....we have a 4800Hz square wave...so starting at the fundamental frequency of 4.8Khz, a square wave (just pretend it's not data for a minute) has an odd harmonic every 4.8Khz from 4.8Khz to....well....30 Mhz, easy? Hmm...100mbit is 100 Mhz. So, there's a carrier buzz around the upper end of the FM band....then there's that 3rd harmonic at 300 Mhz, way above Channel 16, as it were....well? Duhh.... Of course, the wireless network equipment is all built to FCC SPECIFICATIONS (i.e. Type Accepted, Class B Computing Device?) and is SHIELDED to pass?.....well, duhhhh... 2400 Mhz isn't gonna tear up anything on our boat. Will it yours? NONE of the plastic boxes the damned cheap marine crap comes in is shielded in the first place against the HF transmitter or your 5W walkie talkie on deck. Another one: It is NOT necessary to put electronics in a shielded boax to be EMC proof. It all depends on proper PCB layout. A lot of equipment in plastic unshielded boxes carry FCC or CE approval. They don't get that approval when the equipment is radiating like hell or going dead when keying an SSB. May we test your plastic box in the FCC Lab? I can make that arrangement if you like..... Even if the damned thing had the most rudimentary sprayed-on shielding like the monitor you're reading or the computer sitting next to it, it would be an improvement. But, then, of course, I'd want SHIELDED BALANCED WIRES in SHIELDED CONNECTORS, next, wouldn't I.....not some damned fool screw terminals, or worse yet spring terminals like B&G and Raymarine uses, as if we were hooking up a student lab station in a grade school project. You wanna SEE radiation, wait until those cheezy spring terminals corrode against the copper wires making that great DIODE harmonic generator! I've already found two! Whatever happened to those nice metal, waterproof, shielded connectors with all the wires INSIDE the shield, instead of hangin' out the end of a cheap plastic cable with a little tab labeled NMEA (+)? Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
On Sat, 8 Nov 2003 14:49:10 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote: Larry and Todd: It's not quite so simple -- take a look at http://www.mvfintry.com/pix/portland800.jpg. The page cannot be found The page you are looking for might have been removed, had its name changed, or is temporarily unavailable. Please try the following: If you typed the page address in the Address bar, make sure that it is spelled correctly. Open the home page, and then look for links to the information you want. Click the Back button to try another link. HTTP 404 - File not found Internet Information Services Technical Information (for support personnel) More information: Microsoft Support..... Here's the answer to that problem...(c; There are two w/t compartments on the main deck and six below, all possibly with data, as well as tanks. The wheelhouse can also be separated by a w/t door. (Remember that in The Perfect Storm movie, Andrea Gail flooded from the wheelhouse. What really happened, we'll never know.) But, through all those watertight bulkheads, there are wires going through stuffing tubes, right? Are all the wires Navy style with armored shields around them? Maybe you guys are right -- that wireless would work fine -- certainly there are a lot of openings in the bulkheads, although they're all small (2" tops) and sealed with intumescent caulk to keep fire and flood in one place if they happen -- AC, DC, H&C potable water, sal****er fire main, black and gray water, compressed air, diesel, and all the information wires. Oh, the memories. We did an electrical hazard inspection from Shop 51 CNSYD on the USS Saratoga, the old CV in Jacksonville. My God, what a mess she was. 64,000 electrical hits, 29,000 of them Class 1 (must be fixed before restarting the inspection). After two of our tiger team got hurt reaching up into wireways to trace cables they couldn't see, the team leader forbad anyone reaching up into any space he couldn't see his hand in. 440VAC, 400Hz bites HARD! Shake a wireway and sparks shot out all over! Hot wires just layin' up in there! The main electrical feeds go down through the voids on either side of the ship. We traced these big 3phase wires to a bulkhead but they just disappeared on the other side. We found a void noone ever cut a hatch into! The shipfitters cut a hole in it big enough for an inspection hatch and we found three cables, about #0000, DANGLING FROM THE STUFFING TUBES for a length of over 35'! The ship motion had swayed them back and forth, banging them against the bulkheads and wrenching the cables where they went through the stuffing tubes until the bare conductors were breaking apart! All this from the last yard period about 2 years previous. Someone forgot to tie them up and install an inspection hatch! NAVSEA was horrified....(c; The whole inspection was because of that cruiser that caught fire off Lebanon way back in the early 80's and the fire followed the wiring through open, unpacked collars from compartment to compartment. On Saratoga, alone, we ran Florida, Georgia and South Carolina suppliers out of TempSeal to pack them with. Some collars on that carrier are 36" wide by 8-10" high with only a couple of cable running through them! Poor Sara....many she rest in peace. Oh, another fun discovery before I quit. I opened up the fan room that provides fresh air for Central Control, the engineering space where they control all the propulsion from. The huge fan in there puts a big vacuum on this compartment, which gets its intake up a shaft alley under the flight deck. There was a thermostat in there to measure incoming air temperature in the compartment. The capillary tube for this thermostat went through the deck through a FOUR INCH HOLE someone had cut out with a torch, then they dropped the tube down into the compartment below. I got the chief engineer and showed him this hole. "Commander, look down through that hole and tell me what you see.", I requested. "I see some big piece of equipment.", he replied. "We thought so, too. IT'S THE TOP OF THE #2 BOILER! How many people in Central Control will die if that boiler explodes or leaks combustion fumes sucked up by that fan?", I asked, politely. He never answered, running out of the compartment to find the idiot who torched that hole.....Boy he was ****ED! Question then, given that running wire is really easy, because we'll have the conduit for phone, burglar, fire alarm, audio, etc. anyway (sure, maybe all of these can be wireless also, but there are some security issues, etc.), am I better off with wired or wireless? If Larry's right and 802.11 will really reject everything that it might meet, is it a more robust installation to go wireless? This assumes that all of the primary stuff on the bridge is wired -- we're talking about personal computers (in the broader sense of the words) and a couple of non-critical remote readouts here. Naw, in your application, I'd make sure it was all wired. I agree with the other posters hard wires should be the primary feed for data.....however, wouldn't it be nice to be able to see that oil pressure on the #1 engine that faltered and our current course and speed from the notebook in your cabin?.....(c; Or the PDA in your pocket? None of this will go in until we get her on this side of the pond next summer (God willing). I'd be delighted to try it sometime after then.... Good luck to you. Give us a better URL. I'd like to have a look. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
I found all the pictures. What a beautiful project!
Why would anyone with a great-running Lister diesel one couldn't wear out in a lifetime, ever think about replacing it with a truck engine bound to die? God will get you for that, some day..... What a beautiful engine. 750 RPM. Who could wear that out?! Just leave it idle if you don't want to crank it!....(c; Thump......Thump......Thump......Thump......What's idle, 80 RPM? Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... On Sat, 8 Nov 2003 20:09:43 +0100, "Meindert Sprang" wrote: You just take every opportunity for a rant about NMEA, don't you? What rant? The truth is an unshielded RS-232 serial connection with ground hooked to one side of the damned balanced line is a big transmitter! Unshielded plastic crap has no business around an HF receiver with any kind of a switching IC inside it. Well....duhhhh.... That is nonsense. It all depends on proper PCB design. I HAVE measured it, for crying out loud! Why would NMEA at 4800 baud produce more interference than a 100mbit network on UTP (U=Unshielded)? Well, duhhh.....Lemme see....we have a 4800Hz square wave...so starting at the fundamental frequency of 4.8Khz, a square wave (just pretend it's not data for a minute) has an odd harmonic every 4.8Khz from 4.8Khz to....well....30 Mhz, easy? You were talking about interference on 2400MHz, right? Apart from that, have you ever heard of slew rate? A properly filtered 4800 baud output has filters on it, which just cuts off any higher harmonics that can be dangerous. So even with a single wire hooked up to the NMEA output, it can be silent on HF. Hmm...100mbit is 100 Mhz. So, there's a carrier buzz around the upper end of the FM band....then there's that 3rd harmonic at 300 Mhz, way above Channel 16, as it were....well? Duhh.... Of course, the wireless network equipment is all built to FCC SPECIFICATIONS (i.e. Type Accepted, Class B Computing Device?) and is SHIELDED to pass?.....well, duhhhh... 2400 Mhz isn't gonna tear up anything on our boat. Will it yours? Nope. NONE of the plastic boxes the damned cheap marine crap comes in is shielded in the first place against the HF transmitter or your 5W walkie talkie on deck. Yes. Tried it. 15Watts of VHF against the box didn't hurt it. We tested up to 12V/m (that is above the required limits of IEC945) and it kept on working. May we test your plastic box in the FCC Lab? I can make that arrangement if you like..... Please be my guest. Meindert |
Wireless 802.11 NMEA server
Thanks.
As I say on site, the Lister is a real conundrum. I love the thing. It will run forever, even on three cylinders. Absolutely rock solid dependable. It has three ways of cooling (three pumps have to fail to shut it down) and two ways of providing lube oil pressure, can run either wet or dry sump. It has a nice sound. It has temp gauges on every cylinder -- full instrumentation both below and in the wheelhouse. I have an exhaust valve sitting on my desk -- 3.5" diameter x 10" tall. It's a wonder. To start it, you go down in the engine room, turn on the lube oil (remote dry sump), the seawater main, and the 24v to the starter, spin a wheel on the front to decompress, bar the flywheel over a couple of times to make sure everything's free, and push a button on the "Motormatic" box. Relays start clicking, the prelube pump (24v) starts, and oil pressure comes up. When oil pressure hits 50psi, the starter engages. After a quarter turn or so, you spin off the decompress and it starts. The prelube pump stops. You turn off the 24v to the starter and let it warm up for a few minutes. You can shut it down from the wheelhouse, but you have to go down and shut off the lube oil. Now, this is a wonderful sequence, particularly the Motormatic (in this age of computer everything), but can you imagine trying to sell it as a yacht over here in fifteen years? It has a number of little open catch basins for fuel that leaks off. It's hard mounted to huge engine beds, so the whole boat vibrates when it's running -- four huge pistons, and while you can practically count the strokes, they're very present. The official RN manual says that you shouldn't run the boat between 7.5 and 10 knots, only faster or slower (top is 10.3), because of various resonances. Parts are beginning to be a problem (new starter $4,000). And, as also shown graphically on the site, it's huge (see http://www.mvfintry.com/pix/erplan800.png) -- the Cat 3406 is no little thing, but look at the difference. While the engine room is 20 feet square, I've got a lot to go in it and removing the Lister helps. And so forth. I'm sad, though. I'll miss it, except when trying to sleep. -- Jim Woodward www.mvFintry.com .. "Larry W4CSC" wrote in message ... I found all the pictures. What a beautiful project! Why would anyone with a great-running Lister diesel one couldn't wear out in a lifetime, ever think about replacing it with a truck engine bound to die? God will get you for that, some day..... What a beautiful engine. 750 RPM. Who could wear that out?! Just leave it idle if you don't want to crank it!....(c; Thump......Thump......Thump......Thump......What's idle, 80 RPM? Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
On Sun, 9 Nov 2003 10:08:42 +0100, "Meindert Sprang"
wrote: That is nonsense. It all depends on proper PCB design. I HAVE measured it, for crying out loud! Gee, the manufacturers that HAVE to pass FCC specs on radiation don't know that. They spend lots of money coating cases, using metal cabinets, and other shielding. You should go into consulting. Organ manufacturers would love to put out digital organs and keyboards without having to coat the whole thing in tin foil and expensive shielded boxes with foil shielded data lines to pass the FCC tests. Why would NMEA at 4800 baud produce more interference than a 100mbit network on UTP (U=Unshielded)? Well, duhhh.....Lemme see....we have a 4800Hz square wave...so starting at the fundamental frequency of 4.8Khz, a square wave (just pretend it's not data for a minute) has an odd harmonic every 4.8Khz from 4.8Khz to....well....30 Mhz, easy? You were talking about interference on 2400MHz, right? Apart from that, have you ever heard of slew rate? A properly filtered 4800 baud output has filters on it, which just cuts off any higher harmonics that can be dangerous. So even with a single wire hooked up to the NMEA output, it can be silent on HF. Whoa, sport! Your attack on me was about 4800 baud NMEA and it RADIATES LIKE HELL into the HF on every boat I know of because of the way you manufacturers treat the interconnects, dangling the 4800 baud pulses out there in unshielded space. Quit sidestepping the issue. Unshielded 4800 baud data has no place around a submicrovolt HF receiver within a few feet of its receiving antenna.... AS with consumer electronics, until the regulators step in to force the manufacturers to conform to some sort of radiation standard, nothing will change. We'll all still receive expensive new equipment with data wires dangling out open to hook to the cheap terminals on the unshielded plastic boxes...... Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
On Sun, 9 Nov 2003 08:02:07 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote: To start it, you go down in the engine room, turn on the lube oil (remote dry sump), the seawater main, and the 24v to the starter, spin a wheel on the front to decompress, bar the flywheel over a couple of times to make sure everything's free, and push a button on the "Motormatic" box. Relays start clicking, the prelube pump (24v) starts, and oil pressure comes up. When oil pressure hits 50psi, the starter engages. After a quarter turn or so, you spin off the decompress and it starts. The prelube pump stops. You turn off the 24v to the starter and let it warm up for a few minutes. You can shut it down from the wheelhouse, but you have to go down and shut off the lube oil. Wow...prelubing. That thing never runs at all without oil. No wonder the ones 70 years old are still pumping! Thanks for the procedure. Very interesting. Your new diesel will be simple. Flip the switch, Crank the starter and wait while the bare metal scrapes against each other until the oil pressure rises 10 seconds later. Sounds "temporary" doesn't it? No wonder the overhaul shop is packed...(c; Now, this is a wonderful sequence, particularly the Motormatic (in this age of computer everything), but can you imagine trying to sell it as a yacht over here in fifteen years? I'm amazed at the automation. I have visions of a 16mm training film for Lister engineers showing this neatly dressed narrator in his 1934 double-breasted suit pointing out how "Motormatic takes the work out of starting it." I can see you'd have to find a diehard diesel kinda guy to buy it...It's a "manly thing".... It has a number of little open catch basins for fuel that leaks off. It's hard mounted to huge engine beds, so the whole boat vibrates when it's running -- four huge pistons, and while you can practically count the strokes, they're very present. The official RN manual says that you shouldn't run the boat between 7.5 and 10 knots, only faster or slower (top is 10.3), because of various resonances. Parts are beginning to be a problem (new starter $4,000). I have a ham radio friend who is master of SeaLand "Performance", a Dutch-made 950' containership. Performance has a very interesting diesel power plant, 7 cylinders, 38,800HP at 110 RPM, 2-stroke, forced air loop charging. She's about 3 decks high. The cylinders are about 5' in diameter with a 12' stroke. I couldn't pick up the spare injector..(c; She's totally computer controlled! The duty engineer has no need of being in the engine room. The computer will page him on his pocket pager if it detects something it doesn't like. Each injection is computer controlled for best combustion at this throttle setting in each cylinder. It has no transmission or reduction gear. The output shaft, which goes over the main generator room's massive power plants to run all the refridgeration containers on deck, goes directly to the single screw. A picture of the screw in drydock shows his wife standing at the base of a blade that's about three times as tall as she is. The screw is huge! On the engineer's board in the air conditioned control room with windows overlooking the engine gallery, there is a warning sign "DO NOT OPERATE BETWEEN 32 AND 38 RPM". This is the resonant frequency of the ship and engine. They run up through here very rapidly and never operate from 30 to 40 RPM because the engine pulses will rip the hull apart when the whole thing resonates with the engine going one way and the hull the other. Starting is simple. Push the throttle ahead to the position you like. 6000 PSI of compressed air is injected into the proper cylinder just past TDC and #2 diesel fuel sprays into the pressure. The ensuing explosion cranks it as the computer watches on. The compressed air injection stops as the cylinders start firing on their own from just the compression. The computer automatically turns on all the blowers, etc., by itself. Once the engine exhaust comes up to BOIL the bunker oil (one grade above Bunker 'C'), the computer switches the injection over from the expensive #2 home heating oil to the boiling bunker oil that was too thick to inject a little while ago. Now she settles in and at econocruise only burns 75 tons of bunker oil a day to get to Europe. To reverse, pull the throttle back into reverse and the computer goes back to air injection to blast the engine into reverse. Of course, the 2-stroker will run equally well in both directions. Larry says he can do an emergency stop from econocruise in....well....a while. Takes a lot of power to stop all that mass in those boxes... She'll come about in about 2 and a half miles! How's that for a high speed turn? He's been a master for many years. "You never get tired of playing with it.", he tells me. It was a most impressive tour. I'd love to see it running some day. He says the thumping is quite loud in there, something like a diesel pile driver running. And, as also shown graphically on the site, it's huge (see http://www.mvfintry.com/pix/erplan800.png) -- the Cat 3406 is no little thing, but look at the difference. While the engine room is 20 feet square, I've got a lot to go in it and removing the Lister helps. Sorta makes you wonder what Cat left out.....metal? And so forth. I'm sad, though. I'll miss it, except when trying to sleep. I'll bet if its thumping varies, you wake right up, too..... Thanks for the information and your thoughts/story. Great website. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
I think the Cat is the wrong direction for your personality. I sense
that you are a gadget freak like me. Here is the repower option for certain engine nervana. :-) http://www.thesandpebbles.com/san_pa...blo_engine.htm Jim Woodward wrote: Thanks. As I say on site, the Lister is a real conundrum. I love the thing. It will run forever, even on three cylinders. Absolutely rock solid dependable. It has three ways of cooling (three pumps have to fail to shut it down) and two ways of providing lube oil pressure, can run either wet or dry sump. It has a nice sound. It has temp gauges on every cylinder -- full instrumentation both below and in the wheelhouse. I have an exhaust valve sitting on my desk -- 3.5" diameter x 10" tall. It's a wonder. To start it, you go down in the engine room, turn on the lube oil (remote dry sump), the seawater main, and the 24v to the starter, spin a wheel on the front to decompress, bar the flywheel over a couple of times to make sure everything's free, and push a button on the "Motormatic" box. Relays start clicking, the prelube pump (24v) starts, and oil pressure comes up. When oil pressure hits 50psi, the starter engages. After a quarter turn or so, you spin off the decompress and it starts. The prelube pump stops. You turn off the 24v to the starter and let it warm up for a few minutes. You can shut it down from the wheelhouse, but you have to go down and shut off the lube oil. Now, this is a wonderful sequence, particularly the Motormatic (in this age of computer everything), but can you imagine trying to sell it as a yacht over here in fifteen years? It has a number of little open catch basins for fuel that leaks off. It's hard mounted to huge engine beds, so the whole boat vibrates when it's running -- four huge pistons, and while you can practically count the strokes, they're very present. The official RN manual says that you shouldn't run the boat between 7.5 and 10 knots, only faster or slower (top is 10.3), because of various resonances. Parts are beginning to be a problem (new starter $4,000). And, as also shown graphically on the site, it's huge (see http://www.mvfintry.com/pix/erplan800.png) -- the Cat 3406 is no little thing, but look at the difference. While the engine room is 20 feet square, I've got a lot to go in it and removing the Lister helps. And so forth. I'm sad, though. I'll miss it, except when trying to sleep. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
Wireless 802.11 NMEA server
Thanks again.
One can install pre-lube on anything, and I probably will. The CAT weighs around 4,200 pounds with gear, versus 12,000 for the Lister. No one would call 4,200 pounds for 400hp a lightweight engine. I should add that 400hp (which we may never use) is the "run flat out until you have to change the oil" rating. The same block is available in various ratings up to 800hp. I don't think your friend's ship's engine uses 6000psi air to start. That would be 16,000,000 pounds thrust on the 5' piston. 60-100psi or so would be more typical of the air starts I've seen. I've always like air start (that is, with valves -- not an air operated starter motor) as it seemed elegant to use the pistons themselves, rather than this little electric motor. I also like the fact that on vessels smaller than your friend's, you can often hand crank a compressor to do a dead ship start. (Fintry does this with a spring starter on the Perkins 6-354 that used to be a genset and now will be an hydraulic power pack -- it has an electric starter also). Of course you have to have a separate valve train for air, so it's probably more complicated than an electric starter, even if you count the batteries and alternator. On a big engine, though, you don't have much choice. If you ever get a chance, go aboard one of the Liberty ships, or any of the old triple expansion steamers -- the third cylinder is enormous..... -- Jim Woodward www.mvFintry.com .. "Larry W4CSC" wrote in message ... On Sun, 9 Nov 2003 08:02:07 -0500, "Jim Woodward" jameslwoodward at attbi dot com wrote: To start it, you go down in the engine room, turn on the lube oil (remote dry sump), the seawater main, and the 24v to the starter, spin a wheel on the front to decompress, bar the flywheel over a couple of times to make sure everything's free, and push a button on the "Motormatic" box. Relays start clicking, the prelube pump (24v) starts, and oil pressure comes up. When oil pressure hits 50psi, the starter engages. After a quarter turn or so, you spin off the decompress and it starts. The prelube pump stops. You turn off the 24v to the starter and let it warm up for a few minutes. You can shut it down from the wheelhouse, but you have to go down and shut off the lube oil. Wow...prelubing. That thing never runs at all without oil. No wonder the ones 70 years old are still pumping! Thanks for the procedure. Very interesting. Your new diesel will be simple. Flip the switch, Crank the starter and wait while the bare metal scrapes against each other until the oil pressure rises 10 seconds later. Sounds "temporary" doesn't it? No wonder the overhaul shop is packed...(c; Now, this is a wonderful sequence, particularly the Motormatic (in this age of computer everything), but can you imagine trying to sell it as a yacht over here in fifteen years? I'm amazed at the automation. I have visions of a 16mm training film for Lister engineers showing this neatly dressed narrator in his 1934 double-breasted suit pointing out how "Motormatic takes the work out of starting it." I can see you'd have to find a diehard diesel kinda guy to buy it...It's a "manly thing".... It has a number of little open catch basins for fuel that leaks off. It's hard mounted to huge engine beds, so the whole boat vibrates when it's running -- four huge pistons, and while you can practically count the strokes, they're very present. The official RN manual says that you shouldn't run the boat between 7.5 and 10 knots, only faster or slower (top is 10.3), because of various resonances. Parts are beginning to be a problem (new starter $4,000). I have a ham radio friend who is master of SeaLand "Performance", a Dutch-made 950' containership. Performance has a very interesting diesel power plant, 7 cylinders, 38,800HP at 110 RPM, 2-stroke, forced air loop charging. She's about 3 decks high. The cylinders are about 5' in diameter with a 12' stroke. I couldn't pick up the spare injector..(c; She's totally computer controlled! The duty engineer has no need of being in the engine room. The computer will page him on his pocket pager if it detects something it doesn't like. Each injection is computer controlled for best combustion at this throttle setting in each cylinder. It has no transmission or reduction gear. The output shaft, which goes over the main generator room's massive power plants to run all the refridgeration containers on deck, goes directly to the single screw. A picture of the screw in drydock shows his wife standing at the base of a blade that's about three times as tall as she is. The screw is huge! On the engineer's board in the air conditioned control room with windows overlooking the engine gallery, there is a warning sign "DO NOT OPERATE BETWEEN 32 AND 38 RPM". This is the resonant frequency of the ship and engine. They run up through here very rapidly and never operate from 30 to 40 RPM because the engine pulses will rip the hull apart when the whole thing resonates with the engine going one way and the hull the other. Starting is simple. Push the throttle ahead to the position you like. 6000 PSI of compressed air is injected into the proper cylinder just past TDC and #2 diesel fuel sprays into the pressure. The ensuing explosion cranks it as the computer watches on. The compressed air injection stops as the cylinders start firing on their own from just the compression. The computer automatically turns on all the blowers, etc., by itself. Once the engine exhaust comes up to BOIL the bunker oil (one grade above Bunker 'C'), the computer switches the injection over from the expensive #2 home heating oil to the boiling bunker oil that was too thick to inject a little while ago. Now she settles in and at econocruise only burns 75 tons of bunker oil a day to get to Europe. To reverse, pull the throttle back into reverse and the computer goes back to air injection to blast the engine into reverse. Of course, the 2-stroker will run equally well in both directions. Larry says he can do an emergency stop from econocruise in....well....a while. Takes a lot of power to stop all that mass in those boxes... She'll come about in about 2 and a half miles! How's that for a high speed turn? He's been a master for many years. "You never get tired of playing with it.", he tells me. It was a most impressive tour. I'd love to see it running some day. He says the thumping is quite loud in there, something like a diesel pile driver running. And, as also shown graphically on the site, it's huge (see http://www.mvfintry.com/pix/erplan800.png) -- the Cat 3406 is no little thing, but look at the difference. While the engine room is 20 feet square, I've got a lot to go in it and removing the Lister helps. Sorta makes you wonder what Cat left out.....metal? And so forth. I'm sad, though. I'll miss it, except when trying to sleep. I'll bet if its thumping varies, you wake right up, too..... Thanks for the information and your thoughts/story. Great website. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
See my comment to Larry, above -- triple expansion steam is great.
Both of us are machinery nuts -- Dee talks her way onto all sorts of vessels just to see the engine room. We looked at a lot of tugboats in our search for Fintry, and saw a lot of wonderful machines. Finally concluded, though, that tugboats were all engine room and no space for anything else. Who needs 2,000hp in an 80' displacement hull unless you're going to tow something. Otherwise it's just a mechanism for converting diesel into bow wave. -- Jim Woodward www.mvFintry.com .. "Glenn Ashmore" wrote in message news:9esrb.12620$62.6334@lakeread04... I think the Cat is the wrong direction for your personality. I sense that you are a gadget freak like me. Here is the repower option for certain engine nervana. :-) http://www.thesandpebbles.com/san_pa...blo_engine.htm Jim Woodward wrote: Thanks. As I say on site, the Lister is a real conundrum. I love the thing. It will run forever, even on three cylinders. Absolutely rock solid dependable. It has three ways of cooling (three pumps have to fail to shut it down) and two ways of providing lube oil pressure, can run either wet or dry sump. It has a nice sound. It has temp gauges on every cylinder -- full instrumentation both below and in the wheelhouse. I have an exhaust valve sitting on my desk -- 3.5" diameter x 10" tall. It's a wonder. To start it, you go down in the engine room, turn on the lube oil (remote dry sump), the seawater main, and the 24v to the starter, spin a wheel on the front to decompress, bar the flywheel over a couple of times to make sure everything's free, and push a button on the "Motormatic" box. Relays start clicking, the prelube pump (24v) starts, and oil pressure comes up. When oil pressure hits 50psi, the starter engages. After a quarter turn or so, you spin off the decompress and it starts. The prelube pump stops. You turn off the 24v to the starter and let it warm up for a few minutes. You can shut it down from the wheelhouse, but you have to go down and shut off the lube oil. Now, this is a wonderful sequence, particularly the Motormatic (in this age of computer everything), but can you imagine trying to sell it as a yacht over here in fifteen years? It has a number of little open catch basins for fuel that leaks off. It's hard mounted to huge engine beds, so the whole boat vibrates when it's running -- four huge pistons, and while you can practically count the strokes, they're very present. The official RN manual says that you shouldn't run the boat between 7.5 and 10 knots, only faster or slower (top is 10.3), because of various resonances. Parts are beginning to be a problem (new starter $4,000). And, as also shown graphically on the site, it's huge (see http://www.mvfintry.com/pix/erplan800.png) -- the Cat 3406 is no little thing, but look at the difference. While the engine room is 20 feet square, I've got a lot to go in it and removing the Lister helps. And so forth. I'm sad, though. I'll miss it, except when trying to sleep. -- Glenn Ashmore I'm building a 45' cutter in strip/composite. Watch my progress (or lack there of) at: http://www.rutuonline.com Shameless Commercial Division: http://www.spade-anchor-us.com |
Wireless 802.11 NMEA server
Jim,
Wow, what a vessel! Our strategy for these size vessels (and this has only been tested in the lab so I consider it to be pre-beta) is that our wireless navigation servers can be connected together via ethernet cable to get through bulkheads that a wireless signal will not travel. In fact you can connect some of the NMEA devices to 1 wireless nav server and others to the 2nd wireless nav server and any wireless client that connects to either nav server get's all of the nmea data. It remains to be seen how many people will actually want something like this though. For larger vessels where 802.11 signal range presents an issue, we are planning to add wireless mesh networking to the navigation server so you won't need to run any wires to extend the range. This is another configuration that we're working on but will probably only have practical applications in the commercial shipping space or on very large yachts. Cheers, Todd -- Marine Wireless http://www.marinewireless.us "Jim Woodward" jameslwoodward at attbi dot com wrote in message ... Larry and Todd: It's not quite so simple -- take a look at http://www.mvfintry.com/pix/portland800.jpg. There are two w/t compartments on the main deck and six below, all possibly with data, as well as tanks. The wheelhouse can also be separated by a w/t door. (Remember that in The Perfect Storm movie, Andrea Gail flooded from the wheelhouse. What really happened, we'll never know.) Maybe you guys are right -- that wireless would work fine -- certainly there are a lot of openings in the bulkheads, although they're all small (2" tops) and sealed with intumescent caulk to keep fire and flood in one place if they happen -- AC, DC, H&C potable water, sal****er fire main, black and gray water, compressed air, diesel, and all the information wires. Question then, given that running wire is really easy, because we'll have the conduit for phone, burglar, fire alarm, audio, etc. anyway (sure, maybe all of these can be wireless also, but there are some security issues, etc.), am I better off with wired or wireless? If Larry's right and 802.11 will really reject everything that it might meet, is it a more robust installation to go wireless? This assumes that all of the primary stuff on the bridge is wired -- we're talking about personal computers (in the broader sense of the words) and a couple of non-critical remote readouts here. None of this will go in until we get her on this side of the pond next summer (God willing). I'd be delighted to try it sometime after then.... -- Jim Woodward www.mvFintry.com |
Wireless 802.11 NMEA server
On Sun, 9 Nov 2003 10:23:23 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote: If you ever get a chance, go aboard one of the Liberty ships, or any of the old triple expansion steamers -- the third cylinder is enormous..... If you ever get to England, go look at some of the fantastic triple expansion steam engines in museums still working. There are many of them with big webpages to whet your appetite. Simply amazing engines. I've been in the John Brown's engine room. It came to Charleston and I took the tour to support it. She was booked up on the trip up the Cooper, so I trailed her in my jetboat.... Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
On Sun, 9 Nov 2003 10:31:21 -0500, "Jim Woodward" jameslwoodward at
attbi dot com wrote: Who needs 2,000hp in an 80' displacement hull unless you're going to tow something. Otherwise it's just a mechanism for converting diesel into bow wave. I think the same thing every time I see a pleasure trawler with over 125hp or twin engines. What are they going to do, plow up the bottom? We see Super Nordic Tugs on the ICW plowing their way to Florida on their big twin diesels using enormous quantities of diesel as they plow their way through Charleston. Doesn't look like they're any faster than the ones burning far less fuel from a 120 Lehman at a liesurely pace.... How silly. If they're in a hurry, there are jet planes!...... Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... On Sun, 9 Nov 2003 10:08:42 +0100, "Meindert Sprang" wrote: That is nonsense. It all depends on proper PCB design. I HAVE measured it, for crying out loud! Gee, the manufacturers that HAVE to pass FCC specs on radiation don't know that. They spend lots of money coating cases, using metal cabinets, and other shielding. You should go into consulting. Organ manufacturers would love to put out digital organs and keyboards without having to coat the whole thing in tin foil and expensive shielded boxes with foil shielded data lines to pass the FCC tests. Of course it all depends on the application. Certain areas just need complete shielding where extremely low limits are required. All I am saying is that to get something like NMEA equipment quiet and unsusceptible to HF and VHF at reasonable levels like specified in IEC and FCC standards applicable to that kind of equipment, it is not necessary to have everything shielded. And I believe a lot of equipment present on the market prove this statement. And judging from your previous posts here in this group, the interference problems you have had are caused by certain NMEA equipment that is definately not FCC approved. Check the multiplexer and expander you so much prefer: no FCC approval and well known to produce interference. Whoa, sport! Your attack on me was about 4800 baud NMEA and it RADIATES LIKE HELL into the HF on every boat I know of because of the way you manufacturers treat the interconnects, dangling the 4800 baud pulses out there in unshielded space. Quit sidestepping the issue. I am not sidestepping the issue. I just happen to have good experience with NMEA, without any interference on HF. Unshielded 4800 baud data has no place around a submicrovolt HF receiver within a few feet of its receiving antenna.... Like I said befo with properly filtered outputs, which is just mandatory if you want to get something through the IEC of FCC tests, there will be no problem. I mean, it is stupid to have NMEA drivers capable of running at 10Mbaud if you only have to drive 4800 baud. So with the properly dimensioned drivers and RC networks, the slew-rate of the output datasignal is brought back so such a low figure, that there are no significant harmonics present over a few 100 kHz. AS with consumer electronics, until the regulators step in to force the manufacturers to conform to some sort of radiation standard, nothing will change. I don't understand what your implying here. Navigation electronics without specific IEC945 approval falls in the same category as consumer electronics and is therefore subject to the same EMC limits. So there ARE regulations enforced. But we seem to keep on disagreeing on this subject. So lets end this discussion. Best, Meindert |
Wireless 802.11 NMEA server
On Sun, 9 Nov 2003 23:25:24 +0100, "Meindert Sprang"
wrote: And judging from your previous posts here in this group, the interference problems you have had are caused by certain NMEA equipment that is definately not FCC approved. Check the multiplexer and expander you so much prefer: no FCC approval and well known to produce interference. I was waiting for this. I've bypass the Noland and it still tears up MF-HF. If I run just the Garmin and nothing else you can hear it. Any one of the instruments in the boat radiates into the Icom M802 quite badly. The more you turn on, the more noise there is..... Oh, yeah, the Noland, too!....(c; Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... On Sun, 9 Nov 2003 23:25:24 +0100, "Meindert Sprang" wrote: And judging from your previous posts here in this group, the interference problems you have had are caused by certain NMEA equipment that is definately not FCC approved. Check the multiplexer and expander you so much prefer: no FCC approval and well known to produce interference. I was waiting for this. I've bypass the Noland and it still tears up MF-HF. If I run just the Garmin and nothing else you can hear it. Any one of the instruments in the boat radiates into the Icom M802 quite badly. The more you turn on, the more noise there is..... Any chance of using ferrite ringcores on the NMEA lines to surpress it ? Meindert |
Wireless 802.11 NMEA server
On Mon, 10 Nov 2003 07:56:03 +0100, "Meindert Sprang"
wrote: Any chance of using ferrite ringcores on the NMEA lines to surpress it ? Meindert Not as long as the unbalanced lines are all exposed like they are. Every cable from every instrument uses a Belden foil-shielded pair. But the radiation is going to happen, anyway, because the output of some of the instruments is unbalanced, inserting a radiating ground inside the faraday shield. Most instruments, you have to abandon the shield (screen connection for you UK readers) at the point where the instrument's unshielded power cable with its dangling data lead hangs out. There's no way to complete the shielding to the instrument. Maybe Icom is right. Make all the NMEA connections via a coax connector, unbalanced. M802 uses a BNC, in total abandonment of any NMEA balanced concept. The shield of the coax to that BNC MUST be connected to NMEA B (-) to get data on the radio's DSC display. So, I figured RF from the transmitter's case follows this odd ground down into the network shield and screws it all up. But that didn't pan out because the network does the same thing with the cable to the Icom disconnected. Lucky for me that during short SSB transmissions, the system components just ignore the trashed data, so the users don't see there's no NMEA data for the 20 seconds the SSB is talking. I think this is the reason more people don't mention or notice it. The displays just freeze until you stop talking or take a breath when the SSB output power drops to a very low level and data stream resumes. Oddly enough, I don't notice this malady on the Seatalk unbalanced, unshielded part of the system. This may be because its cables are much shorter and all the Seatalk instruments are very close together. (RL70CRC Plus, Smart Heading Sensor, WAAS-GPS). Even the GPS receiver built into its antenna has a very short cable because I found a great little unused place right on top of the helm to port of the crank handle for the main sheet traveler to put both Garmin and Raymarine GPS antennas. Coverage through the fiberglass hardtop on the cockpit is excellent and noone uses the antenna for a grabhandle like they did when the antennas were initially on top of the hardtop. It's cable to the Seatalk plastic box with European screw terminals is only about 10" long. None of the Seatalk wires are over 24", making them much too short to fit an 8 Mhz wavelength. Seatalk radiates, too, even on these short cables. If I shut down the whole NMEA network and just run the RL70CRC Plus, WAAS-GPS and Smart Heading Sensor with the NMEA cables unplugged from the RL70, I can still hear data noise from the Seatalk across the HF bands. Someone knows about this because none of the Seatalk harmonics is on a marine HF channel. I only have a few in the ham bands. It's just too bad there isn't a STANDARD everyone was FORCED to follow that would completely eliminate this easily-fixed interference. USB and RS-232C and RS-422 running at home don't tear up my ham station sitting right next to the computer. I just can't believe marine electronics cannot be built for these lofty prices that doesn't interfere, either. Ferrites won't stop the plastic boxes and unshielded cables with square waves in them from radiating unless you rounded off the edges, which would trash the data timing. The computers in the plastic boxes also radiate. Doesn't take much to trash a submicrovolt receiver and open its squelch. We used to have an Adler-Barbour 12V electronic-controlled cold plate that just ATE, of all frequencies, Channel 16 with its incessant pulsing, opening the squelch of all the VHF receivers with a maddeningly repetitive pulsing shuusssh of the closing squelch.....It only trashed 16, the channel you listen to most. Drove all the helmsmen crazy until we figured out what it was and shut it down. It's someone else's problem now. This fridge runs off a 1-cyl engine compressor. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
Wireless 802.11 NMEA server
"Larry W4CSC" wrote in message
... On Mon, 10 Nov 2003 07:56:03 +0100, "Meindert Sprang" wrote: Any chance of using ferrite ringcores on the NMEA lines to surpress it ? Meindert Not as long as the unbalanced lines are all exposed like they are. Every cable from every instrument uses a Belden foil-shielded pair. But the radiation is going to happen, anyway, because the output of some of the instruments is unbalanced, inserting a radiating ground inside the faraday shield. Most instruments, you have to abandon the shield (screen connection for you UK readers) at the point where the instrument's unshielded power cable with its dangling data lead hangs out. There's no way to complete the shielding to the instrument. But you only connect the shielding on the transmitting side of the cable, right? Never connect shielding on both sides unless it is part of the data connection. It is always better to have signal and return in a pair, shielded by a screen that is connected on the TX side. Maybe Icom is right. Make all the NMEA connections via a coax connector, unbalanced. M802 uses a BNC, in total abandonment of any NMEA balanced concept. The shield of the coax to that BNC MUST be connected to NMEA B (-) to get data on the radio's DSC display. Hold on! That cannot be right. If the NMEA source you connect to the M802 has a NMEA A (+) and a NMEA B (-) line, it is a balanced output where both wires are 'live'. If you connect that to the BNC of the M802, which is unbalanced (BNC is grounded), you'll effectively short circuit the NMEA B to ground. In such a case, you only connect the NMEA A to the input and the ground of the NMEA talker to the ground of the listener. you should leave the NMEA B unconnected. So, I figured RF from the transmitter's case follows this odd ground down into the network shield and screws it all up. But that didn't pan out because the network does the same thing with the cable to the Icom disconnected. Lucky for me that during short SSB transmissions, the system components just ignore the trashed data, so the users don't see there's no NMEA data for the 20 seconds the SSB is talking. I think this is the reason more people don't mention or notice it. The displays just freeze until you stop talking or take a breath when the SSB output power drops to a very low level and data stream resumes. Normally this kind of interference could be solved by looping the NMEA wires through ringcores, effectively breaking the antenna formed by the wires. Oddly enough, I don't notice this malady on the Seatalk unbalanced, unshielded part of the system. This may be because its cables are much shorter and all the Seatalk instruments are very close together. (RL70CRC Plus, Smart Heading Sensor, WAAS-GPS). Even the GPS receiver built into its antenna has a very short cable because I found a great little unused place right on top of the helm to port of the crank handle for the main sheet traveler to put both Garmin and Raymarine GPS antennas. Coverage through the fiberglass hardtop on the cockpit is excellent and noone uses the antenna for a grabhandle like they did when the antennas were initially on top of the hardtop. It's cable to the Seatalk plastic box with European screw terminals is only about 10" long. None of the Seatalk wires are over 24", making them much too short to fit an 8 Mhz wavelength. Indeed. And if the NMEA wires are longer, you can 'break' them by using ringcores. Ferrites won't stop the plastic boxes and unshielded cables with square waves in them from radiating unless you rounded off the edges, which would trash the data timing. No problem to round off the edges. I have for instance, put RC networks on the NMEA outputs. You can see the round-offs but a UART samples the signal on several (mostly 16) positions within one bit time. So slow slopes on the signal are no problem. It's not egde-driven but level driven. Meindert |
Wireless 802.11 NMEA server
On Mon, 10 Nov 2003 15:01:06 +0100, "Meindert Sprang"
wrote: "Larry W4CSC" wrote in message ... On Mon, 10 Nov 2003 07:56:03 +0100, "Meindert Sprang" wrote: Any chance of using ferrite ringcores on the NMEA lines to surpress it ? Meindert Not as long as the unbalanced lines are all exposed like they are. Every cable from every instrument uses a Belden foil-shielded pair. But the radiation is going to happen, anyway, because the output of some of the instruments is unbalanced, inserting a radiating ground inside the faraday shield. Most instruments, you have to abandon the shield (screen connection for you UK readers) at the point where the instrument's unshielded power cable with its dangling data lead hangs out. There's no way to complete the shielding to the instrument. But you only connect the shielding on the transmitting side of the cable, right? Never connect shielding on both sides unless it is part of the data connection. It is always better to have signal and return in a pair, shielded by a screen that is connected on the TX side. It's all connected as a Faraday shield on one end only. Sure wish it were foil coax in a sealed environment, dammit. This open crap around screws eats my shorts. Maybe Icom is right. Make all the NMEA connections via a coax connector, unbalanced. M802 uses a BNC, in total abandonment of any NMEA balanced concept. The shield of the coax to that BNC MUST be connected to NMEA B (-) to get data on the radio's DSC display. Hold on! That cannot be right. If the NMEA source you connect to the M802 has a NMEA A (+) and a NMEA B (-) line, it is a balanced output where both wires are 'live'. If you connect that to the BNC of the M802, which is unbalanced (BNC is grounded), you'll effectively short circuit the NMEA B to ground. In such a case, you only connect the NMEA A to the input and the ground of the NMEA talker to the ground of the listener. you should leave the NMEA B unconnected. Won't work unless you connect the coax shield of the BNC connector (radio ground) to the NMEA -. This is EXACTLY what I'm talking about! MANY of the instruments you buy has NO BALANCED NMEA lines! The RL70CRC NMEA inputs are balanced lines....The Garmin are not. The Icom is not. NMEA (-) B input to the VHF is grounded hard inside the box. It's input is unbalanced, too. Yeoman's input and output is unbalanced, as is the B&G Network instruments. None of these have a real NMEA (-) and will NOT read data hooked from NMEA + to screen/shield/ground, from the multiplexer or any balanced NMEA transmitter source hooked up independently. You can't connect it if IT AIN'T THERE!.... So, I figured RF from the transmitter's case follows this odd ground down into the network shield and screws it all up. But that didn't pan out because the network does the same thing with the cable to the Icom disconnected. Lucky for me that during short SSB transmissions, the system components just ignore the trashed data, so the users don't see there's no NMEA data for the 20 seconds the SSB is talking. I think this is the reason more people don't mention or notice it. The displays just freeze until you stop talking or take a breath when the SSB output power drops to a very low level and data stream resumes. Normally this kind of interference could be solved by looping the NMEA wires through ringcores, effectively breaking the antenna formed by the wires. Oddly enough, I don't notice this malady on the Seatalk unbalanced, unshielded part of the system. This may be because its cables are much shorter and all the Seatalk instruments are very close together. (RL70CRC Plus, Smart Heading Sensor, WAAS-GPS). Even the GPS receiver built into its antenna has a very short cable because I found a great little unused place right on top of the helm to port of the crank handle for the main sheet traveler to put both Garmin and Raymarine GPS antennas. Coverage through the fiberglass hardtop on the cockpit is excellent and noone uses the antenna for a grabhandle like they did when the antennas were initially on top of the hardtop. It's cable to the Seatalk plastic box with European screw terminals is only about 10" long. None of the Seatalk wires are over 24", making them much too short to fit an 8 Mhz wavelength. Indeed. And if the NMEA wires are longer, you can 'break' them by using ringcores. Oh, boy, let's patch it......screw that. Let's fix the manufacturing problems and STANDARDIZE! Ferrites won't stop the plastic boxes and unshielded cables with square waves in them from radiating unless you rounded off the edges, which would trash the data timing. No problem to round off the edges. I have for instance, put RC networks on the NMEA outputs. You can see the round-offs but a UART samples the signal on several (mostly 16) positions within one bit time. So slow slopes on the signal are no problem. It's not egde-driven but level driven. Meindert I gave up trying to make it quiet. I got it lowered a bit in strength, but it's still buzzing away like a cheap SCR light control all over the place........ If there's a REAL emergency I HAVE to hear, I'll just shut it down and use the radio in PEACE. Larry W4CSC "Very funny, Scotty! Now, BEAM ME MY CLOTHES! KIRK OUT!" |
| All times are GMT +1. The time now is 10:40 PM. |
|
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 BoatBanter.com