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Registered Member #179
Joined: Thu Feb 16 2006, 02:08AM
Location: Hagerstown, Maryland - Close to Prime Outlets
Posts: 287
...so that I can do a low power broadcast of a TV show to my entire house. I have a modulator that is channel 3 or 4, and I know that it is in essence a very low power transmitter. Can I connect an RF power amp for the TV VHF range to that, connect an antenna, and tune it in on any regular TV?
Registered Member #1630
Joined: Sat Aug 09 2008, 11:36AM
Location: Seoul Korea
Posts: 115
ShawnLG wrote ...
I don't think this is legal. It is agains the FCC rules. There are some consumer products out there that can do wireless video/audio link.
for your own house it is NOT illegal. A VCR uses (some of them) a cable that is connected to your TV, at least i had a few that did that. Wireless transmission is strictly regulated however. Transmitters past 500mW? (don't quote me on the strength) require a HAM radio certificate from the FCC-- same category as UHF radios. You can buy small 100mW trasmitters that broadcast out to 3000ft line of sight, but these are easily interffered with by a microwave, wireless router or simular device.
Registered Member #179
Joined: Thu Feb 16 2006, 02:08AM
Location: Hagerstown, Maryland - Close to Prime Outlets
Posts: 287
Alright guys, I'm not planning to transmit to the neighborhood...just a few MW to reach my interior walls, and with the size of my yard, even the neighbors wouldn't pick it up.
Registered Member #103
Joined: Thu Feb 09 2006, 08:16PM
Location: Derby, UK
Posts: 845
If you're thinking of using a TV 'aerial booster' as your RF amp that won't be very effective. I think you'll need more power than you think to get a clear TV picture anywhere in the house, especially as all the TVs will have their aerials pointing in random directions. I reckon you'll need about 1 watt broadcast from a dipole in the center of the house, just search for a broadband VHF power amp on the net and throw something together. Alternatively, you might even get a stronger signal by broadcasting from outside, back at your house - directly at the TV antennas which I assume you already have set up pointing outside
Registered Member #1630
Joined: Sat Aug 09 2008, 11:36AM
Location: Seoul Korea
Posts: 115
Bored Chemist wrote ...
Am I the only one who sees the irony in this "I'm not planning to transmit to the neighborhood...just a few MW ".
that should be mW .. MW holy cow, I think this guy has a massive Turbo diesil generator in his basement with a plan on ruling the airwaves to start the next revolution.
Registered Member #30
Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706
Well, getting back on topic... I don't see any reason why it wouldn't work, provided you can get or make a suitable power amp, which could be difficult at TV frequencies.
If one aerial booster doesn't bust out enough power, how about 5 daisy-chained together? Or maybe you could replace the amplifier chip in the booster with a more powerful MMIC.
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Want to amplify the RF of a video modulator...
Or maybe you could replace the amplifier chip in the booster with a more powerful MMIC.