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Custom tuned video transmitter antennas


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#1 Robert Starling SOC

Robert Starling SOC

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Posted 06 March 2007 - 09:21 PM

Harkening back to my days as an amatuer radio operator I tracked down an antenna company today who will custom cut and manufacture video transmitter antennas to your specific frequency requests / needs.

An antenna is only truely (at least nearly) perfect on a specific frequency; the farther you move from that center, the less effective the antenna is. Transmitter power is robbed by high SWR and dissipated in the form of heat. You can easily loose more than 50% of the power especially with multi channel transmitters. The better quality transmitters have "tuner" circuitry inside to fake out the transmitter so it doesn't burn up but you're still not getting the power to the antenna where you need it. Considering you can only have optimal performance about 5 mhz to either side of a tuned frequency, and if you look at the fact that a Modulus spans about 225 mhz, if you're only using one antenna you're loosing ground fast.

The company is Smiley Antenna 1-800-527-5439 and they've been around for at least the 20 plus years since I've been licensed. They only make antennas.

The basic product is listed as a Slim Line 1/4 wave 440 mhz antenna but they custom make them to your frequency specs (amatuer radio is not allocated in the 500-900 mhz range so it's not a stock item). Here's the link:

http://www.smileyant...;products_id=48

Here is a link to the frequency list for US TV broadcast channels.

http://www.rf-links....tv_channels.htm

The good news is they're only $16 each with BNC connector.

If you want more information on antennas and radio wave characteristics here is a link to a Forum posting I wrote a few months ago:

http://www.steadicam...x...ic=3882&hl=
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#2 Lawrence Karman

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Posted 06 March 2007 - 11:38 PM

Thanks for the info.
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#3 Frenzy

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Posted 18 April 2007 - 03:06 PM

Katie Holmes touching her boobs!
http://Katie-Holmes-...hp?movie=698419
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