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HelixEasystar

Problems with 900MHz-500mW system..HELP

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Hi ppl

I have some problems with my system (900 mhz-500mhz) and i was hoping that someone could help me?

The problem is that when i have connected the batteries,camera(KX-191 from rangevideo) to a LCD screen i just see a black screen???!!! But when im moving the TX antenna around, the screen blurs and change a little bit. But No IMAGE:

Im using lipo 3 cell 800mah on the camera and TX .

I have tried with antenna paths and the orginal antenna but no image..

Is there anyone that have any idea of what can be wrong??

I have tested the camera and it works fine and the TX is getting hot (heard that it was a good thing)

thx for all help :)

Helix from Norway..

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I'd suggest you check the freq DIP switches. Sometimes they are labeled backwards. So, try various settings to see if you stumble upon a match.

Does the black screen turn to random snow if you turn off the Tx? If it does, then it would mean that you have Tx RF present (a good thing), but probably have a problem in the camera/Tx wiring or the DIP switches are wrong.

Beyond that, it might help to see some clear close-up photos of how the camera is wired to the Tx.

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I'd suggest you check the freq DIP switches. Sometimes they are labeled backwards. So, try various settings to see if you stumble upon a match.

Does the black screen turn to random snow if you turn off the Tx? If it does, then it would mean that you have Tx RF present (a good thing), but probably have a problem in the camera/Tx wiring or the DIP switches are wrong.

Beyond that, it might help to see some clear close-up photos of how the camera is wired to the Tx.

Hi.

* I have checkd the freq in all different ways a hope. just the same response..

* Yea the screen turns to snow when i unplugg the TX..

* It can be the wiring between cam and TX,,but how can i check that??

Espen

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It can be the wiring between cam and TX, but how can i check that??

Remove power from the system. Leave everything else as-is.

Unplug the 4-pin cable from the video Tx.

Using your ohmmeter set to a low ohms scale, measure the resistance across the yel and black pins of the Tx cable.

It should be 70-80 ohms, or something close. What do you measure?

BTW, what camera are you using?

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Remove power from the system. Leave everything else as-is.

Unplug the 4-pin cable from the video Tx.

Using your ohmmeter set to a low ohms scale, measure the resistance across the yel and black pins of the Tx cable.

It should be 70-80 ohms, or something close. What do you measure?

BTW, what camera are you using?

Hi.

I have mesured the resistance now and i get no response on the voltometer...???

It has to be the cable then since,everything else works..

Espen

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Just use the ohmmeter to troubleshoot the video signal paths on your cables.

BTW, what camera are you using?

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Hi yea im gonna try that.. I used a voltometer and with that i got no response..

I use the KX 191 cam from rangevideo..

Just use the ohmmeter to troubleshoot the video signal paths on your cables.

BTW, what camera are you using?

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Just so there is no confusion, troubleshoot the video cable using an ohmmeter and not a voltmeter. If you are using a multimeter, then it would be set to ohms.

I can't say for sure on the KX-171 since I don't have one, but the video input on an industry standard designed camera should be close to 75 ohms. That is what should have been measured in the earlier test. Since you found an open circuit, is shouldn't take but a couple minutes to find the defective cable (or bad cable adapter if one is used).

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Hi sorry for the late reply..

I have now measured the camera cabel and it was 75 ohm... And the TX is getting hot but not the camera!!

So you say that i have to just get a new camera cabel then and it should work??

I have tested the wires and after 10 min try out the TX is hot and camera is still cold..

So that concloud that is the wireing then?!

Just so there is no confusion, troubleshoot the video cable using an ohmmeter and not a voltmeter. If you are using a multimeter, then it would be set to ohms.

I can't say for sure on the KX-171 since I don't have one, but the video input on an industry standard designed camera should be close to 75 ohms. That is what should have been measured in the earlier test. Since you found an open circuit, is shouldn't take but a couple minutes to find the defective cable (or bad cable adapter if one is used).

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Just continue to troubleshoot it. It shouldn't take but a couple minutes to see if 12VDC is getting all the way to the camera. You can use your voltmeter for that.

Plus, don't forget the best troubleshooting tool in the toolbox is your eyeballs. So zoom them onto the power connectors (and cables) and look for problems.

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Should try to plug your camera directly on a tv to know if it works. And, if not, on the tv, it will be easier to troubleshoot.

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I know what you are going through. I have found that you MUST turn things on in a certain order for it to work. Firstly the camera, then the video transmitter, then the receiver. If I turn on the video transmitter first, then the camera...it doesn't work!!!

Ross

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