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Sorry for being so lengthy

Recently picked up a wireless spy cam and a DSB-V100 USB Video Capture Device off ebay for my RC plane and/or heli. The cam of course for the platform and the DSB-V100 for the laptop at the field to video my flights. I do not own a camcorder so the laptop was the next best thing. By connecting the wireless reciever to the USB-V100 then previewing and recording using windows movie maker.

I of course have tested the cam in the house on my home TV and attached to a rc truck and drove it down the block and back, over 200'. from the living room TV the reception was great, sat on the couch the whole time as a FPV. Tuned in the freq no problem and I was off.

Now the problem: Connected it up to the DSB-V100 and laptop onto window movie maker, the reception was very difficult to tune in, then the line of site was only a couple of feet and very jumpy and wouldn't stay clear more than a few seconds. Is the laptop putting of too much freq through the cables or am I missing more hardware somewhere.

Thanks for all your help and knowledge :angry:

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To get a handle on this problem, you need to determine where the suspected EMI/RFI is coming from. Your symptoms suggest it is related to the frame grabber or PC. But, these problems can manifest in many different ways, so the actual source can be elsewhere (RFI can be conducted or radiated). If it isn't the grabber, it could easily be the PC or some other accessory connected to it.

Merely trying another framegrabber isn't a reliable solution, but it might just help. None will have the necessary EMI/RFI suppression needed to prevent a closely coupled UHF/Microwave receiver with high sensitivity from getting dorked signals. That part is up to you.

One last thing. If you leave all the cables plugged in and then disconnect the grabber's USB cable from the PC, does the range improve? If so, then the problem is related to the grabber, the PC, or anything else attached to that part of the system. Try toroidial cores on all the cables.

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Keep in mind there is a short delay between what is transmitted and what you see on the computer screen. If you are tuning the RX by looking at the computer screen, you are very likely going past the optimal setting because you stop moving the tuning knob when the image on the laptop looks good. Unfortunately this good looking image actually occurred a half second ago at a previous tuning-knob setting. The result is a slightly off-tuned receiver.

To prove (or disprove this theory), get the tuning "close", then move the transmitter farther away until you experience the degraded range. Then try retuning the reciever very slowly. If my theory is right, you will have a maddening experience of getting the tuning right, only to have the signal disappear a half second later. At that point, simply move the receiver knob a small fraction and wait a half second to see the result. Repeat until you get the best picture.

I hope that is the problem!

Regards,

Bill

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I have tested against the laptop and the picture is there, tuned in and have a picture but if the cam moves to much then the picture is lost. Iv'e tried replacing the cheap antennea that came with the rx with a piece of coaxial cable, but how long is a nother question.

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