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#1
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Thanks again for everyone's input.
To clarify why I am installing a SSB. My boat is a 28' documented vessel with a fisheries endorsement. I fish commercially as much as 100 nm from shore. Any documented commercial fishing vessel operating outside of VHF radio range from shore stations (maybe 25-30 miles on a good day) is required by the Commercial Fishing Vessel Safety Act to carry a MF/HF radio. I have my FCC ship station license and restricted radiotelephone operator permit. I also have a 406 MHz Type 2 EPIRB (also required by law) and other safety devices too numerous to name (also required by law). All I really need to be able to do is contact the nearest shore stations. I'm not looking to talk halfway around the world. Now back to the installation. I'm leaning toward a guyed installation on the pilot house roof. This will get the antenna up and away from all metal structures. I drew up a sketch of the concept, but I still can't seem to upload any picture files to this server. I'm planning on going with a Shakespeare 5390 17.5' fiberglass coated whip. I'm thinking of attaching three stainless guy wires about 4' up from the base. The idea I have for attaching anchors for the guy wires is to fabricate three aluminum brackets with holes to clip the guy wires to and installing them 120° apart on the antenna whip by wrapping them with fiberglass tape and encapsulating with resin, much the same way that the eyes on fishing rods are attached to the rod blanks. The stainless steel guy wires will attach to three points on the edge of the pilot house roof. My question is will these metal brackets and guy wires cause problems with antenna performance (or roast the occupants of the boat)? The brackets will be electrically isolated from the conductors inside the whip by the fiberglass coating on the whip, but will RF energy still be affected (shunted down through the guy wires to the pilot house)? Does anyone else have any other ideas? Brad |
#2
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posted to rec.boats.electronics
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The shorter whip should hold up better than the long one. It would be
good to determine the frequencies your coast stations will be using and confirm that your antenna tuner will handle those frequencies with the 17 foot whip. You don't want to use metal guy wires so close to the antenna. Dacron would probably be a better choice than stainless for the guys. It also has some stretch to it. I would think 3/16" braided dacron would be more than adequate for the purpose. The metal wires could affect antenna performance, but there's no real danger to people in the pilothouse. There's another advantage to aluminum! The greater difficulty is that if you attach the guys at 8 feet up, the angles to the corners of the pilothouse will be really small, which is not so good. It would be better at 3-4 feet up, but they guys won't help much if they are that low. You'll probably get some additional insights as you mount and attempt to guy the antenna. If the pilothouse roof is aluminum, you're in good shape. Mount the tuner close to the base of the antenna and you should be fine. Good luck! Chuck bradleyj wrote: Thanks again for everyone's input. To clarify why I am installing a SSB. My boat is a 28' documented vessel with a fisheries endorsement. I fish commercially as much as 100 nm from shore. Any documented commercial fishing vessel operating outside of VHF radio range from shore stations (maybe 25-30 miles on a good day) is required by the Commercial Fishing Vessel Safety Act to carry a MF/HF radio. I have my FCC ship station license and restricted radiotelephone operator permit. I also have a 406 MHz Type 2 EPIRB (also required by law) and other safety devices too numerous to name (also required by law). All I really need to be able to do is contact the nearest shore stations. I'm not looking to talk halfway around the world. Now back to the installation. I'm leaning toward a guyed installation on the pilot house roof. This will get the antenna up and away from all metal structures. I drew up a sketch of the concept, but I still can't seem to upload any picture files to this server. I'm planning on going with a Shakespeare 5390 17.5' fiberglass coated whip. I'm thinking of attaching three stainless guy wires about 4' up from the base. The idea I have for attaching anchors for the guy wires is to fabricate three aluminum brackets with holes to clip the guy wires to and installing them 120° apart on the antenna whip by wrapping them with fiberglass tape and encapsulating with resin, much the same way that the eyes on fishing rods are attached to the rod blanks. The stainless steel guy wires will attach to three points on the edge of the pilot house roof. My question is will these metal brackets and guy wires cause problems with antenna performance (or roast the occupants of the boat)? The brackets will be electrically isolated from the conductors inside the whip by the fiberglass coating on the whip, but will RF energy still be affected (shunted down through the guy wires to the pilot house)? Does anyone else have any other ideas? Brad |
#3
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posted to rec.boats.electronics
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bradleyj wrote in
: I'm thinking of attaching three stainless guy wires about 4' up from the base. Oops....nope. The guy wires must not become part of the radiator, which wire will do. The guys should be line, not wire. Use the kind of line you'd see on a sailboat topping lift and you'll do fine. It's good the line flexes some as the fiberglass whip is designed to flex some and that takes the stress off everything. You can make a 3-point metal plate that will slip over the smaller, upper part of the whip, but with a hole that won't pass the metal part where it widens, which I think happens two times on this antenna you're considering. Slip the whip through the hole and let it seat itself down the mast with further securing. It isn't going anywhere. The small metal plate is too small to make any big RF statement on HF. This gives you a tiepoint for the small supporting, INSULATING, line to tie off to your cabin roof points. The fold-down mount will then be easy. Release one line, maybe use a clip on it to tie it to the boat and she'll fold right over for trailering, which I can see makes my previous fixed suggestion impossible. Bolt the HF antenna tuner to the top of the cabin right beside the base so the folding doesn't hit it (port or starboard) and keep the "hot" lead from the tuner to the antenna as short as possible. Be sure to ground the tuner's ground lug to a ring terminal bolted to the cabin roof, as short as possible, with a heavy strap. Coat the connections with some grease to keep the water away from them and seal it up. This ground will make the whole boat the ground counterpoise and turn the plastic blowboat HF users green with envy for your great ground plane. Wouldn't two DIESELS be much cheaper and lots more reliable than outboard gas guzzlers in a commercial operation??? |
#4
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Wouldn't two DIESELS be much cheaper and lots more reliable than outboard
gas guzzlers in a commercial operation???[/quote] Yes, diesels would be prefereable. However this hull was specifically designed for twin outboards. It has a transom extension for mounting the outboards. The hull is also pretty shallow, so there's not much space for engines under the deck. As for costs, the outboards were MUCH cheaper to purchase than diesels would have been, especially since I got them used. These are relatively new direct injected, computer controlled 2-strokes and the boat is pretty light (about 5000 lbs dry), so I get great gas mileage; about 2 mpg crusing at 25 knots. What I'd really love would be a pair of 150 HP diesel OUTBOARDS, but I don't think there's any such thing. Having two engines covers me on reliability. I can still make over 25 knots on one motor. Full speed at WOT on both motors is almost 40 knots. One of the earlier posts mentions RF noise concerns from the motors. Any other opinions on this? I could line the motor cowls with aluminum foil if this would help. Also, with a 17.5' antenna, at what frequencies would I have best performance at? What kind of ranges could I expect? The only really important frequency for me is 2182 kHz (int'l distress). I need to be able to contact local Coast Guard stations (several of which will be less than 150 miles away at any given time) on this frequency in an emergency. Last edited by bradleyj : February 1st 06 at 02:47 PM |
#5
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bradleyj wrote in
: These are relatively new direct injected, computer controlled 2-strokes and the boat is pretty light (about 5000 lbs dry), so I get great gas mileage; about 2 mpg crusing at 25 knots. What I'd really love would be Oh, God.....Please tell me they are NOT Ficht engines that you're going to sea with...Please.... |
#6
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bradleyj wrote in
: One of the earlier posts mentions RF noise concerns from the motors. Any other opinions on this? I could line the motor cowls with aluminum foil if this would help. If these are Ficht engines, I doubt you'll ever hear anything, foil or not, on an HF radio. Hell, they wipe out a 5KW AM on 1250 in the harbor! The computers and that stupid injection system blowtorch eating the heads off the spark plugs..all those make incredible RF noise. You'd never be able to shield it all as it sneaks out every wire going to the console, its own antenna. Please tell me those are not Ficht engines....How awful. |
#7
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On Wed, 1 Feb 2006 14:08:56 +0000, bradleyj
wrote: The only really important frequency for me is 2182 kHz Actually not since it is not much used anymore, lots of reasons. 4125 khz is probably your best bet under most conditions. Here is more information: http://www.navcen.uscg.gov/marcomms/...ewFreq2005.htm Regarding engine noise, time will tell. At idle with a good radio and noise supression circuitry, it may not be that bad. You can get noise supressed plugs and wires if need be. Alternators can be an issue also. |
#8
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Yes everyone, they are Ficht engines. After doing a tremendous amount of research on these motors prior to buying them (including conversations with mechanics who have worked on them), I came to the conclusion that the modifications that OMC made to address the design defects originally present in these motors did the trick. As part of these mods, these particular motors were refitted with redesigned cylinder heads, fuel system modifications and new ECU software. These motors were installed on a NMFS vessel in Alaska for four years. When they repowered their fleet in 2003, I purchased them with about 325 hours on them and put another 100 trouble-free hours on them myself last year. I do the vast majority of my fishing within 20 miles of shore and when I do go offshore, I never go out more than about 100 miles. The chances of both engines failing simultaneously is pretty remote.
If any one of you badmouthing the Fichts has ever owned one and had problems with it I'd like to hear your story. I'll be a bit surprised if anyone can offer anything more than "I know someone who knows someone....". The original design of these motors was definitely deficient and their fix came too late. It contributed substantially to the ruination of OMC, more through the loss of reputation than the quality of their products. |
#9
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I was surprised to find your post in this NG, but what the heck. :=)
I have owned and operated a 1998 FICHT since buying it new in 1999. I've had no parts failures and the only work ever done on the OB was spark plug replacement and ECU updates. The engine is quiet, efficient, and clean burning. There is no soot on my prop hub and the thing never smokes. There is an interesting thread by FICHT owners on either thehulltruth.com or boatfix.com forums, sorry I don't remember which. Butch "bradleyj" wrote in message ... Yes everyone, they are Ficht engines. After doing a tremendous amount of research on these motors prior to buying them (including conversations with mechanics who have worked on them), I came to the conclusion that the modifications that OMC made to address the design defects originally present in these motors did the trick. As part of these mods, these particular motors were refitted with redesigned cylinder heads, fuel system modifications and new ECU software. These motors were installed on a NMFS vessel in Alaska for four years. When they repowered their fleet in 2003, I purchased them with about 325 hours on them and put another 100 trouble-free hours on them myself last year. I do the vast majority of my fishing within 20 miles of shore and when I do go offshore, I never go out more than about 100 miles. The chances of both engines failing simultaneously is pretty remote. If any one of you badmouthing the Fichts has ever owned one and had problems with it I'd like to hear your story. I'll be a bit surprised if anyone can offer anything more than "I know someone who knows someone....". The original design of these motors was definitely deficient and their fix came too late. It contributed substantially to the ruination of OMC, more through the loss of reputation than the quality of their products. -- bradleyj |
#10
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In article ,
bradleyj wrote: Thanks agaifor everyone's input. To clarifwhy I am installing a SSB. My boat is a 28' documented vessel with a fisheries endorsement. I fish commercially as much as 100 nm from shore. snipped for brevity....... Noback to the installation. I'm leaning toward a guyed installation on the pilot house roof. This will get the antenna up and away from all metal structures. I drew up a sketch of the concept, but I still can't seem to upload any picture files to this server. I'm planning on going with a Shakespeare 5390 17.5' fiberglass coated whip. I'm thinking of attaching three stainless guy wires about 4' up from the base. The idea I have for attaching anchors for the guy wires is to fabricate three aluminum brackets with holes to clip the guy wires to and installing them 120apart on the antenna whip by wrapping them with fiberglass tape and encapsulating with resin, much the same way that the eyes on fishing rods are attached to the rod blanks. The stainless steel guy wires will attach to three points on the edge of the pilot house roof. My question is will these metal brackets and guy wires cause problems with antenna performance (or roast the occupants of the boat)? The brackets will be electrically isolated from the conductors inside the whip by the fiberglass coating on the whip, but will RF energy still be affected (shunted down through the guy wires to the pilot house)? Does anyone else have any other ideas? Ok, now we have just about enough information to make some relativly speaking, informed observations. 1. A 17.5 Ft unloaded whip isn't going to be much of a radiator in the MF/HF Marine Radio Bands, below 8 Mhz, no matter what autotuner you put under it. 2. Just who are you planning to talk to with this MF/HF Radio? Most of the High Seas Public Corespondence Stations went off the air a decade ago, so that leaves Private Coast Stations, which may or may not want to handle your traffic, unless you actually setup a scheduale with them. 3. You maybe are thinking that the local USCG will actually be listening to the High Seas Calling Frequencies, and they actually, may be, but for your operational area, the MF and low HF Frequencies give the comm's for that area, and your antenna isn't actually going to preform good enough to allow resonable expectation of succesful communications. 4. As Larry states, it is a very good thing that you have a 406 EPIRB aboard for Distress Alerting, because if you are depending on the above MF/HF Radio to save your life, best you get lots of Life Insurance, and buy a Plot before you go out past VHF coverage. 5. I suppose you could have a Wx Ballon and Hydrogen Canister aboard and use that to lift a decent length MF Antenna for Emergency Communications, but just how well are you going to be able to do that while in an Emergency Situation. Yea, Yea I know that the FVSA says you have to fit a MF/HF Radio in order to be out passed VHF Coverage, in Sea Area A2, but in that area it is designated that MF comms should be used, and your Antenna System is going to be more like a Dummy Load, at MF Frequencies than an antenna. Bruce in alaska -- add a 2 before @ |
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