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VGA over CAT5e
Hi Guys,
I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al |
VGA over CAT5e
wrote in message
... Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al Al Well I was going to say different cable for different uses, but then I found this site: http://www.geocities.com/dougburbidge/vgaovercat5.html The author says they've achieved 15 metres. For the cost of the cable and solder time, worth trying. If that doesn't work you can get gadgets that convert from VGA to RJ45 and back again: http://www.svideo.com/vgacat5.html Best Paul. |
VGA over CAT5e
wrote:
Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al This cable, has a round connector in the center, and is intended to make it easier to penetrate walls. This cable is 50ft long, and claims to support 1600x1200 (refresh rate not stated, could be 60Hz). http://www.tripplite.com/EN/products...xtModelID=3351 Look for more "Easy Pull" items here. They also make DVI and HDMI versions. http://www.tripplite.com/EN/products...?txtEntryID=32 In all the advertising cruft on the pages, it doesn't state what the O.D. of the connector is. It looks like it might be 1" diameter or so, but hard to say for sure. It mentions pulling through 3/4" conduit here. That is, if you trust marketing people to pull cables. http://www.tripplite.com/shared/lite...yer/952906.pdf Another brand example here. RapidRun modular cabling system. 3/4" conduit. http://www.cablemeister.com/product.php?productid=50731 They also make RGBHV to VGA breakout cables. Such a cable would be missing signals for DDC (used by a computer to get resolution information from a monitor), but cables like this are sometimes used for projector devices connected to computers. Your application would probably be happy with the basic RGBHV signals. RGB is color, HV are sync signals. There are several ways to carry sync, including sync on green. So again, the requirements can vary a bit, and having all five RGBHV helps cover all possibilities. http://www.ramelectronics.net/render...ts/VGA2BNC.jpg The idea would be, you make the hole big enough, to pass the BNC connectors one at a time. The example picture above, has made the BNC connectors excessively fancy. A little extra slack on the five coaxes, would probably help. The solution is less ideal than the RapidRun, but perhaps easier to buy locally. You can connect the BNCs with some coax wires with mating BNCs on the end. I suppose you could buy BNC kits, as long as they're designed for the thin coax, and simply fit crimp BNCs on the end of each coax. So that would be another possibility. If soldering a VGA connector, the hard part would be connecting the RGB coax signals. Coax and soldering don't mix. Which is why I put so many "pull" style solutions in the above :-) If you visited me two hours after giving me a soldering job like that to do, I'd be in "full cuss mode". The insulation inside coax melts easily. Paul |
VGA over CAT5e
On Oct 6, 5:55*pm, Wayne.B wrote:
On Sun, 5 Oct 2008 21:05:00 -0700 (PDT), wrote: Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. http://www.google.com/search?hl=en&q...t+vga+extender generates 257,000 *hits. http://www.google.com/search?hl=en&q=kvm+cat5+extender generates 140, 000 hits. Here's a few that look promising: http://sewelldirect.com/KVMcat5extender.asp http://www.cablestogo.com/product.as...=503&sku=39970 Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? You would need the skills of a micro-surgeon and a very fine solder tip. I am liking the ethernet idea. I found these mounts I could use which have sealed end caps for when not in use: http://au.farnell.com/1254803/connec...ol-pcd-rjfrb71 This way it has a fighting chance of surviving in the marine enviroment! -Al |
VGA over CAT5e
writes:
Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. How about cutting the connector from one cable end, pulling the cable and then soldering a new one to the end. Or building entirely new VGA cable the length you want by soldering the connectors yourself to both ends. The soldering the cable consisting of several mini coax condictors and many other conductor DB15 VGA connector is not the easiest job, but doable if you are good at building cables. I have done that kind of soldering myself when I have needed some custon VGA cables for some applications. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. Runnign VGA over CAT5e is possible. There are commercial active adapters that do the conversion "right" and work even for some longer distances. Those cost money but work quite well. Then in Internet there are some simple plans to run VGA over CAT5e cables. When you use a shielded CAT5e cable and not too long distances, those hacks can work quite well but might not give perfect "crystal clear" picture like a real VGA cable or commercial converter would give. Running VGA signal on unshielded CAT5e cable with simple DIY passive adapters is not a vry good idea: the image quality will get worse and your cable will radiate out considerable RF interference which could interfere for example with boat radios. I was wondering if anyone had any better ideas, keeping costs fairly low. I just gave you several ideas. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Yes. I have done this several times. -- Tomi Engdahl (http://www.iki.fi/then/) Take a look at my electronics web links and documents at http://www.epanorama.net/ |
VGA over CAT5e
wrote in message
... Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. You have lots of replies to this already, but just curious as to whether you've considered instead putting a small laptop in your "bridge" and using remote desktop or vnc to control your "Nav Station" (assuming its a standard pc). You could even go wireless and avoid the need for cable runs all together. -- Brian Cryer www.cryer.co.uk/brian |
VGA over CAT5e
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VGA over CAT5e
wrote in message ... Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al VGA cable is shielded and CAT5 is not, so you would get some horrible ghosting. BTW, there may still be some ghosting even with VGA cable |
VGA over CAT5e
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VGA over CAT5e
On Mon, 6 Oct 2008 17:23:03 +1300, "PeeCee" wrote:
wrote in message ... Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al Al Well I was going to say different cable for different uses, but then I found this site: http://www.geocities.com/dougburbidge/vgaovercat5.html The author says they've achieved 15 metres. For the cost of the cable and solder time, worth trying. I used to make up VGA cables for control room applications. 15M using individual screened conductors was about the recommended limit If that doesn't work you can get gadgets that convert from VGA to RJ45 and back again: http://www.svideo.com/vgacat5.html Best Paul. |
VGA over CAT5e
"philo" wrote in message ... wrote in message ... Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al VGA cable is shielded and CAT5 is not, so you would get some horrible ghosting. BTW, there may still be some ghosting even with VGA cable STP CAT5e or CAT 6 would do the trick, and at these lengths the cost difference isn't an issue. -John O |
VGA over CAT5e
Alfred wrote:
On Sun, 5 Oct 2008 21:05:00 -0700 (PDT), wrote: Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? If you are handy with a soldering iron there is no problem. You may have to buy a new plug/socket though as the one you cut off may be potted. Unfortunately, unless you do this for a living, one is unlikely to have a nice temperature controlled iron with a micro-chisel tip, like a MetCal. I've spent most of my adult life doing this and fine soldering without ballsing things up is both an art and a skill, takes practise, a good eye and a steady hand. Buy an adaptor and use the Cat5 or 6 route, probably be a lot less headache. Cheers Marty |
VGA over CAT5e
It might be worthwhile to think-out a bit beyond the size of the hole
though which you want to pass this signal. Stuff like "what will hold-up best when I'm at the bridge, in a storm, near a rocky shore and I really need to know where I am?" I say that only half in jest. rick jones -- oxymoron n, commuter in a gas-guzzling luxury SUV with an American flag these opinions are mine, all mine; HP might not want them anyway... :) feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH... |
VGA over CAT5e
In article ,
glen herrmannsfeldt wrote: JohnO wrote: "philo" wrote in message (snip) VGA cable is shielded and CAT5 is not, so you would get some horrible ghosting. BTW, there may still be some ghosting even with VGA cable STP CAT5e or CAT 6 would do the trick, and at these lengths the cost difference isn't an issue. There might be a minimum amount that they will sell, but the real problem isn't shielding but impedance and balanced/unbalanced line. If you transition from a balanced line (UTP) to an unbalanced line (coax), unless exactly impedance matched, it won't work right. UTP cable depends on the voltage and currents on the two wires being exactly opposite to cancel out and not radiate the signal. Coax depends on the voltage on the shield being zero. To couple between them you either need a transformer (if there is no DC component), or active circuitry such as differential amplifiers. VGA has a DC component so you can't use transformers. -- glen You can use a transformer, but wired as a *balun* (coils in series with the lines instead of across them); this provides the required impedance transformation while still passing DC. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
VGA over CAT5e
JohnO wrote:
"philo" wrote in message (snip) VGA cable is shielded and CAT5 is not, so you would get some horrible ghosting. BTW, there may still be some ghosting even with VGA cable STP CAT5e or CAT 6 would do the trick, and at these lengths the cost difference isn't an issue. There might be a minimum amount that they will sell, but the real problem isn't shielding but impedance and balanced/unbalanced line. If you transition from a balanced line (UTP) to an unbalanced line (coax), unless exactly impedance matched, it won't work right. UTP cable depends on the voltage and currents on the two wires being exactly opposite to cancel out and not radiate the signal. Coax depends on the voltage on the shield being zero. To couple between them you either need a transformer (if there is no DC component), or active circuitry such as differential amplifiers. VGA has a DC component so you can't use transformers. -- glen |
VGA over CAT5e
Rich Seifert wrote:
(snip) You can use a transformer, but wired as a *balun* (coils in series with the lines instead of across them); this provides the required impedance transformation while still passing DC. So that is how they do it. TV baluns, from 300 ohm balanced to 75 ohm coax, don't do that. http://en.wikipedia.org/wiki/Balun Does that restrict which impedance transformation you can make? -- glen |
VGA over CAT5e
On 6 Oct, 18:30, Rick Jones wrote:
It might be worthwhile to think-out a bit beyond the size of the hole though which you want to pass this signal. *Stuff like "what will hold-up best when I'm at the bridge, in a storm, near a rocky shore and I really need to know where I am?" *I say that only half in jest. I have worked with commercial solutions using this technology. Was about 5 or 6 years ago. I forget the name of the product. One serious problem was that by *design* (as I understand it) the various different pairs in the cat5 cable have different twist rates. This results in different cable lengths and produces different delays for each of the RGB and Sync. The solution overcame this by having user adjustable delays controlled by DIP switches at the remote end. (or is sync on one of the RGB?) doesn't matter - is still broken. NIGHTMARE - in the event of any moves or changes. Not sure of your proposed length would run into this or not. I suspect it would since the frequency required to drive a display is rather high. In the case I observed the differential delay issue was *very* significant over two floors of a narrow buillding. There of course may be commercial solutions available now that avoid the problems entirely. Perhaps by combining the signals into one pair. Composite Video? |
VGA over CAT5e
On Mon, 6 Oct 2008 16:27:41 -0700 (PDT), wrote:
There of course may be commercial solutions available now that avoid the problems entirely. Perhaps by combining the signals into one pair. The most common solution now is to use an ethernet KVM (keyboard, video and mouse) switch. All signals get packetized. |
VGA over CAT5e
On Oct 7, 3:55*am, Martin Baxter wrote:
Alfred wrote: On Sun, 5 Oct 2008 21:05:00 -0700 (PDT), wrote: Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? If you are handy with a soldering iron there is no problem. You may have to buy a new plug/socket though as the one you cut off may be potted. Unfortunately, unless you do this for a living, one is unlikely to have a nice temperature controlled iron with a micro-chisel tip, like a MetCal.. I've spent most of my adult life doing this and fine soldering without ballsing things up is both an art and a skill, takes practise, a good eye and a steady hand. Buy an adaptor and use the Cat5 or 6 route, probably be a lot less headache. Cheers Marty Haha. Actually I am lucky - I have a Hakko 936 Temp Controlled Iron, but have found a place I can buy a HD15 connector I can use with crimp pins - this might be easier than trying to solder it? |
VGA over CAT5e
Not sure of your proposed length would run into this or not. I suspect it would since the frequency required to drive a display is rather high. Length in this case 4m absolute MAX! -Al |
VGA over CAT5e
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VGA over CAT5e
"philo" writes:
wrote in message ... Hi Guys, I need to get a VGA signal from the Nav Station in my boat to the monitor in the bridge. I could just run a VGA cable (about 4m worth) but I need to pass the cable through some small holes for the looming (sp?) and the DB15 connectors wont fit unless I make the hole bigger. I am thinking about running the VGA singal over CAT5e, which a Google search seems to suggest is possible. I was wondering if anyone had any better ideas, keeping costs fairly low. Has anyone here had any success cutting the end off a VGA cable and wiring on a new DB15 for example? Thanks in advance, -Al VGA cable is shielded and CAT5 is not, so you would get some horrible ghosting. Thethe wrong cable impedance and lack of shileding between RGB signals will not cause ghosting. Most ghosting will be caused by the impedance mismatches. The lack of shield in cable will cause that that cable will pick up more easily external interference and will radiate out more RF interference and properly shielded VGA cable. BTW, there may still be some ghosting even with VGA cable True. The VGA cables vary in quality. The good ones are good but there are also bad ones. One thing to keep in mind in VGA connections is that it is a good idea to keep the number of VGA connectors along the link minimum (ideally only at source and destination), because the VGA connector impedance is not exactly 75 ohms as the system is designed for, and having many such wrong impedance connectors on the way will cause impedanc mismatches that cause reflections. For VGA cables is best to use a correct length cable in the beginning, and avoid using orignal cable + extension cable combinations. -- Tomi Engdahl (http://www.iki.fi/then/) Take a look at my electronics web links and documents at http://www.epanorama.net/ |
VGA over CAT5e
In article ,
glen herrmannsfeldt wrote: Rich Seifert wrote: (snip) You can use a transformer, but wired as a *balun* (coils in series with the lines instead of across them); this provides the required impedance transformation while still passing DC. So that is how they do it. TV baluns, from 300 ohm balanced to 75 ohm coax, don't do that. http://en.wikipedia.org/wiki/Balun Does that restrict which impedance transformation you can make? The impedance transformation is determined by the winding ratio, regardless of whether the coils are in series or parallel with the lines. Putting the balun in series provides better low-frequency response (down to DC), but of course this configuration does not provide any electrical isolation. It functions very much like a common-mode choke, with an impedance change. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
VGA over CAT5e
"Alfred" wrote in message
... On Mon, 6 Oct 2008 17:23:03 +1300, "PeeCee" wrote: snip I used to make up VGA cables for control room applications. 15M using individual screened conductors was about the recommended limit mmm wouldn't surprise me. I've seen VGA extension cables as short as 2M exhibit ghosting. P. |
VGA over CAT5e
"PeeCee" writes:
"Alfred" wrote in message ... On Mon, 6 Oct 2008 17:23:03 +1300, "PeeCee" wrote: snip I used to make up VGA cables for control room applications. 15M using individual screened conductors was about the recommended limit mmm wouldn't surprise me. I've seen VGA extension cables as short as 2M exhibit ghosting. There are well built VGA extension cables (use 75 ohm mini coax cables at least for RGB signals). Those work generally well. Also there are those crappy cables built just from general purpose computer cable with lots of wires inside one outer shield. Those cheap cables have typically wrong impedance and considerable crosstalk between signals - ghosting problems Then the used resolution + refresh combination has effect. Almost any crapphy cable works for 640x480 60 Hz resolution but for 1280x12o4 and higher resolutions the quality of the cable starts really slow up. -- Tomi Engdahl (http://www.iki.fi/then/) Take a look at my electronics web links and documents at http://www.epanorama.net/ |
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