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Video System Wiring - Help?

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Hi all, I'm new to RC-CAM and expect to be hanging around here quite a bit; great information!

I picked up a Tx, Rx, and small CCD camera without any wires or cables; price was right. Now I need some advise on wiring the video system. Specifically, what kind of wire or cable and connectors should I use, and where specifically I can buy such supplies? So....type and gauge power wire from the battery to the transmitter and camera. Also, what kind of cable is required from camera to transmitter for video. I have attached a wiring diagram of what I plan if that will help, and a pic my tx and cam minus the battery and two DE regulators. Just to let you know, I did have it wired up at one point using just 18awg speaker wire to test. It does work, but with a lot of interference.

I did a search and found a coax cable that might work well. Take a look when you get the chance http://bwccat.belden.com/ecat/pdf/179DT.pdf. The cable has an nominal diameter of .1" (2.54mm) and is shielded. States it is suitable for digital video. I would think that both the power cables and video cable would have to consist of some sort of shielding from EMI and other types of interference. As shown in the pic, I have the wire that connects into the cam, but would like to replace that as it is old and does not look to very efficient.

Before I install this on my Logo10, I will play around with it on my TrexSE, so I am trying to keep the cabling as light a possible without compromising integrity of video signal. Basically, I will be mounting cam on a small gimbal on the front of the Trex. The av sys batt will be up front as well as the av tx.

So apart from what type/gauge cabling, would anyone also have any specific online sources?

post-5-1168111935_thumb.jpg

Edited by qb7

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You will have interference, it's better to use a second battery for the video

it's too long to answer you, frankly at the price they sell video tx & rx, I will put your stock in the garbage and start with new 100mW or 500mW tx

These video tx are very hard to make it work well, and you started very badly...

Edited by Vrflyer

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I'm a little more optimistic on this setup. The camera is a Panasonic CX-161, which is a nice color CCD (actually, it is my favorite board camera). The Video Tx is interesting looking. Looks like a ham radio design from plans or a kit. What freq is it and how much RF power does it put out? What does the Rx look like? Do you have detailed information on the system? (I'm just curious about its origins).

Going to the trouble to use shielded cable for power and video is just not worth the effort. I do realize that the video signal should be routed with 75 ohm coax, but the short lengths just don't warrant that. As far as wire gauge goes, 24 AWG is typical, but even 26AWG is useful. Keep the wires as short as possible!

Those DE DC-DC Vregs will probably create video interference unless you construct a decent low pass LC filter on the power supply lines. In other words, be prepared for some frustration. It might be a good idea to start with a linear VReg (LM2940 or similar), get it to work, then introduce the noisy switcher supplies when you have confidence to do so.

If you are not experienced with soldering and constructing electronic circuits, then I advise that you find an Elmer to give you some hands on help. Otherwise, it may all go up in smoke.

Just to let you know, I did have it wired up at one point using just 18awg speaker wire to test. It does work, but with a lot of interference.

There are many types of "interference." Without specific details it could mean anything (good or bad). You should post a video link to an example if you need help resolving the noise.

As VRflyer mentioned, don't share the video system battery with the model's motor or r/c gear. At some point you can experiment with doing that, but this is not the time to encourage trouble.

So apart from what type/gauge cabling, would anyone also have any specific online sources?

This is the place. Brew a pot of coffee and read every post on this forum. Also visit the old rc-cam msn forum for even more info. Just learn from our past mistakes, most of which have been discussed over the years.

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Yep, most of what you want to know is on thes forum somewhere ! You just have to be able to find it :)

Your transmitter looks good, I guess its about 500mW. The only worry I have with it is that there seems to be no screening, just heatsrink. I would add a thin tin cover not too close to the componants or make sure its not too close to anything when installed. Good luck.

Terry

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You will have interference, it's better to use a second battery for the video

I use an AnyVoltMini on my RC car so the camera+transmitter are powered directly from the car's battery and I don't get any inteference on the transmitted video signal.

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Yes Haku it can work, but for a first attempt its better not to use a switcher as more people have had problems using one than have not.

Terry

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And the problems is not on the video signal, it's more the receiver onboard the planes that will be affect and lost range. For a r/c car, it's not important unless you want to go very far. Also on a planes we have long wire that pick up the noise around, r/c car are small so no long wire, so perhaps you will not note any lost on r/c car.

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You will have interference, it's better to use a second battery for the video

it's too long to answer you, frankly at the price they sell video tx & rx, I will put your stock in the garbage and start with new 100mW or 500mW tx

These video tx are very hard to make it work well, and you started very badly...

I had an IT problem, so just getting back to replying now.

I actually plan to use a 2nd battery. I'm not sure about the one I listed, but has to power the tx, cam, and two servos on a micro gimbal. I will probably start off with a smaller one and work my way up to what will work best. My reason for taking this route is to learn from scratch about how the system ticks. If for some reason it wont't operate effectively once together, then I will definately punt it and buy a packaged system.

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I'm a little more optimistic on this setup. The camera is a Panasonic CX-151, which is a nice color CCD (actually, it is my favorite board camera). The Video Tx is interesting looking. Looks like a ham radio design from plans or a kit. What freq is it and how much RF power does it put out? What does the Rx look like? Do you have detailed information on the system? (I'm just curious about its origins).

Thomas, thanks for the heads up on the Camera model as no one could ID it until now. I sent pics of the cam, Tx and Rx to Videocomm. They could not ID the Rx and Cam, but figured the Tx was indeed theirs and most likely a model T-2495 Series (2.4Ghz 900mW). That's about all I know about I sent a pic to Videocomm to confirm and they said it looked more like their That's all I know about the Tx. Theydo not think the Rx was a Videocomm. I will post a few pics and maybe get lucky with you recognizing it!

post-5-1168260685_thumb.jpg

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Going to the trouble to use shielded cable for power and video is just not worth the effort. I do realize that the video signal should be routed with 75 ohm coax, but the short lengths just don't warrant that. As far as wire gauge goes, 24 AWG is typical, but even 26AWG is useful. Keep the wires as short as possible!

Roger that on the video cable and 24-26AWG wire.

Those DE DC-DC Vregs will probably create video interference unless you construct a decent low pass LC filter on the power supply lines. In other words, be prepared for some frustration. It might be a good idea to start with a linear VReg (LM2940 or similar), get it to work, then introduce the noisy switcher supplies when you have confidence to do so.

Edited by qb7

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The only worry I have with it is that there seems to be no screening, just heatsrink. I would add a thin tin cover not too close to the componants or make sure its not too close to anything when installed. Good luck.

Terry

Terry, Can you expand on the tin cover screening? Is this with respect to EMI? Also, what are Tx's typically wrapped with (the black material)? I have heard of a guy who was doing a photo shoot of cell-towers, and mitigated interference by wrapping his Tx in tin foil. If we are talking about protection from both the elements and EMI, what about a large diameter wrap of the EMC shrinkMate at the following link? http://cableorganizer.com/heat-shrink/cond...heat-shrink.htm.

Edited by qb7

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And the problems is not on the video signal, it's more the receiver onboard the planes that will be affect and lost range. For a r/c car, it's not important unless you want to go very far. Also on a planes we have long wire that pick up the noise around, r/c car are small so no long wire, so perhaps you will not note any lost on r/c car.

Bonjour VrFlyer. I am a "Canuk" also! But have not lived in Canada for many years. Decided to leave the white stuff and reside in the tropics. I have followed some of your talk on first person video, and will be pursing that also in the near future. So, expect a PM or two!

Thanks all again for you help on this.

Lachlan

Edited by qb7

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Terry, Can you expand on the tin cover screening? Is this with respect to EMI? Also, what are Tx's typically wrapped with (the black material)?

I will try, all I mean is to put a sheild to stop any outside forces from detuning your TX. Yes think EMI but not the record company :)

I have not seen the black material, probably just heat shrink.

Here is a pic of my 459Mhz R/C receiver which shows a tin screen in use, I hope it helps.

post-5-1168267349_thumb.jpg

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I will try, all I mean is to put a sheild to stop any outside forces from detuning your TX. Yes think EMI but not the record company :)

I have not seen the black material, probably just heat shrink.

Here is a pic of my 459Mhz R/C receiver which shows a tin screen in use, I hope it helps.

Heh, heh! Roger on the record company! Thanks for the pic; go the idea.

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I checked the new photos of your tx, and finally it's not look to bad.

I did not saw their best side. It's happens also with womens sometimes :)

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Ya, both (tx/women) are quite similar; ya take off a layer or two and you may find something quite different. Could be good, could be scary! :D

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