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Attention: RC-CAM.com will be closing down August 2021.

The RC-Cam.com forum was the very first online community dedicated to the advancement of wireless video cameras on radio controlled (R/C) models. This is now called "FPV" (First Person View). We are proud of the contributions that our members have made to the FPV hobby.

We've seen significant changes over the last twenty years. Initially there were a lot of eager R/C hobbyist that built their own video systems. Allowing these creative individuals to share their work was the purpose of this site. Now the FPV market is flooded with low cost systems; Sadly DiY FPV video projects are now rarely discussed.

RC-CAM.com (main site and forum) will be closing down August 2021. This was announced several months ago (March 2021) to allow our members ample time to download any information that is important to them. After the site is shutdown the information will no longer be available here.

We appreciate every member's involvement with advancing the FPV hobby. It is indeed sad to say goodbye to all our online friends. Be safe and stay healthy.



900mhz antenna questions


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Hello to all. I'm doing as much reading as I can on antennas for 900mhz video use but I have some questions...

First, everyone seems to recommend the rangevideo whip for the transmitter. I cannot see how this antenna, being only 4.5", long can be a true half wave. Is not a half wave for 900 mhz closer to 6.5"? Can anyone explain?

Also, the rangevideo patch antenna is also a hit with RC but it has what appears to be quite a long cable. Mr. RC states, in his article on how to build a patch antenna, that the normal coax cable causes much signal strength loss. Again, can anyone shed some light?

Hope I'm not nitpicking... just trying to understand is all : )

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Mr. RC states, in his article on how to build a patch antenna, that the normal coax cable causes much signal strength loss. Again, can anyone shed some light?

In the 2.4GHz GP Patch project, coax is highly discourage due to the cable's losses at that frequency. However, coax attenuation at ~900MHz is substantially lower (assuming it is wisely chosen cable). So short lengths of good coax on a 900MHz system are practical. But if you want the most performance then keep it as short as possible.

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