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cdog4w

new to wireless cams, need help with rc car use

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To begin, this site is great, tons of useful information. I've been reading up and have a rough plan of what I can do to improve video quality. To start, this is the specific cam I purchased (looks to be the most recent version of the HK cam):

http://www.geeks.com/details.asp?invtid=20...-50MW-N&cat=VID

And here is the test video (divx 5.11) I shot on a small RC in my office (captured on a desktop using a hauppauge wintv-go pci card):

http://cstanleyw4.home.comcast.net/rc/cam_on_car.avi

In the video, the camera was running on a 9V battery. The included AC adapter runs at 8V DC and the "instructions" say ~6-12V. The camera was simply taped to the top of the car, no damping whatsoever. As you can see it is also an office environment with plenty of computers, fleorescent lighting and other fun things to throw off the signal. Unfortunately I would like to use this in a similar environment, an indoor rc track.

On to my problem and questions. If you watch the video, you will see flashes of color while the car is in motion. The picture is good enough for me when stationary. Since I'm ground based, range will not be as important as picture quality.

-It seems like the best solution would be to first build a patch antenna for the receiver. Unfortunately I don't have access to a frequency counter and cannot afford to purchase one currently. I will try calling an electronics store to see if they would let me test by bringing the camera + 9V to the store, but I doubt I will have luck there. If this fails I will attempt using 1.1GHz or so since most people have said there system is around that frequency. I am also wondering if this type of antenna is suitable for rc car use. Seems like the answer is yes if oriented properly. Also of note is that the connector on the receiver is normal coax (type F I think?) and not SMA.

-People also suggest that the 9V battery is a poor power source and a regulated power supply would be better. If this is the case, I could either patch into the car's lipo (2 cell, peaks at 8.4V and is usually around 7.5V when I'm done) or get a separate lipo to power the camera/transmitter. Not regulated but better than a 9V?

-If that doesn't solve it, my next step would be to mod the transmitter antenna. The ground plane antenna is recommended, but I also noticed that the antenna is not cut to the proper length (as debated in multiple threads) and is about 3.5" or 90mm. It seems people have had luck cutting it to 65mm, but I would rather leave modding the transmitter to the last resort. I have basic rc soldering skills so I could probably replace the antenna if the cut to 65mm doesn't work.

Thanks in advance for any help!

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Getting good mobile performance indoors is tough. But, your plans may improve things enough to reduce the multipathing seen in your video.

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