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I understand that you are using a video camera and Tx combination that does not work with your camcorder when the GP707 is used (some minor video tearing due to video content)

--This is correct, I may add colour render problems and image horizontal bar deviations to the right

Additional problems (lack of color, contrast, etc.) are seen on the recorded image when you 'Y' the camcorder with your glasses (note: a common issue with simple Y'd video cables).

--Correct, but also true when GP707 is connected directly to JVC camcorder, not true when I use the FS634rx, even with Y

But this Rx works fine with your glasses or video monitor,

--Also correct, although the camcorder maintain the problems above reported

even while Y'd with the camcorder.

Not true, the image is grainier than with FS634rx when have the JVC splitting the signal

Furthermore, the camcorder works fine with the AWM634 Rx. You have found that the camcorder's video input is Hi-Z.

--Correct!

Thomas,

I want to thank you once more for your time and patience.

Furthermore, I made a video self explanatory where you can see all the things I am trying to put here in words.

http://www.vimeo.com/3045408

If you have a vimeo account, I invite you to download it and see it at 720x576.

Thanks again.

Edited by jalves

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How many 75 ohm resistors do you have? We can make a variety of terminator values for test purposes by stringing several together.

Top on my list is to see if we can make the GP707 work with the camcorder, with no other video devices. If we fail doing that, there is no need to move on.

BTW, I could not watch the video at this time (received the "waiting in line" warning).

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This tests were done without any resistor added, only the original wires, no modification at all.

As you said, we need to recap, that's what I did.

Top on my list is to see if we can make the GP707 work with the camcorder, with no other video devices. If we fail doing that, there is no need to move on.

Acknowledge!

Per comparison, the GP707 has always a darker image than his FS634rx counterpart, the Y degrades MUCH more the GP707 image than the FS634rx, in this one, is almost unnoticed.

Edited by jalves

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How many 75 ohm resistors do you have?

IIRC only 3 of them.

Please, say How many and the value of the resistors We need, I'll buy it tomorrow (is plain night here).

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For a quick test, use three (four if you have them) 75 ohm resistors in series to create a larger value (225 - 300 ohms). Use this as a terminator on the input of the camcorder. Directly connect the GP707 to it. Ignoring any color or brightness issues, does the video tearing problem become less offensive? If this helps, then obtain the variety of resistors mentioned earlier for further testing.

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I use three 75Ohm in series, connect signal to ground.

Only noticed that the principal horizontal video bar slide down a bit. All the tears in video maintained (also color and brightness problems)

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Because the tears are still there, that suggests that there will be little hope to solve the problem with terminator tricks. At this point I'd recommend you change the Rx to something that is known to be compatible with your video system.

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Because the tears are still there, that suggests that there will be little hope to solve the problem with terminator tricks. At this point I'd recommend you change the Rx to something that is known to be compatible with your video system.

Ok,

One last question:

Is all the video splitter the type I post above??

If I want a GOOD active video splitter, what should I search for (the problem here is they all have the same specs).

Thanks again for your help.

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The consumer video splitters that look like yours are nearly all the same design (cloned and copied by several China sources). If you need adjustable gain, then I don't know of any to recommend that would be much different. If you don't need a gain pot, then NG Hobbies has a buffer board that has 75 ohm terminations (but be sure to request the new/latest design, not the older one).

I don't believe you will get any joy from another video buffer. The symptoms suggest you have other issues besides basic signal level problems. But, if you try one and get good results, then be sure to report back here. :)

It seems to me that the only offending item is the GP707, so wouldn't it be simpler to just use an AWM634 Receiver, or something else that is fully compatible with your existing system? The buffer you have now should work with the AWM634 too, so you would be able to continue using it too.

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The consumer video splitters that look like yours are nearly all the same design (cloned and copied by several China sources). If you need adjustable gain, then I don't know of any to recommend that would be much different. If you don't need a gain pot, then NG Hobbies has a buffer board that has 75 ohm terminations (but be sure to request the new/latest design, not the older one).

I don't believe you will get any joy from another video buffer. The symptoms suggest you have other issues besides basic signal level problems. But, if you try one and get good results, then be sure to report back here. :)

It seems to me that the only offending item is the GP707, so wouldn't it be simpler to just use an AWM634 Receiver, or something else that is fully compatible with your existing system? The buffer you have now should work with the AWM634 too, so you would be able to continue using it too.

Ok Thomas,

I won't forget to post here if I solve GP707/JVC problem.

Many thanks for your help.

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Just want to add that I bought a 7'' lcd television with AV in, no problem with airwaves based receiver, but the little gem was incapable of displaying the image received by the GP707, what a "lemon" receiver this is!

Edited by jalves

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I guess you got a defective unit, or a bad quality "copy" from some 3rd party manufacturer. The original definitely is good :)

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Or it could be a version with an incompatible pre-emphasis modulation or the operating frequencies could be off a bit. These would affect bandwidth and harm video sync performance (your problem appears to be related to horizontal syncs). But, the first thing to suspect would be a defective unit. If it is still under warranty you could try to get an exchange.

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They look the same as the ones I used in my 4 way system, I had to tune them all in by gently squashing or streatching one of the tuning coils, maybe the one that you can see through the hole (I dont remember).

Terry

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Interesting. I have seen at least 6 different designs for those, and this is even completely different. None of those I've seen had a coax inside for example...

You should compare with your friend's one. And yes, send it for an exchange.

Edited by Kilrah

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