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Transmitters


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I just purchased another transmitter, as yet another backup. Its a 11/2 watt transmitter and receiver.Its from a company out of this country so who knows what it will be like. The price was right, at around $800.00 for the total package including a 5" LED t.v. moniter. It is microwave at 1.2GHz.I believe it runs on a police frequency. Have any of you ever had a real unpleasent experience with the law due to illegal transmissions? Thanks for any and all feedback. Good shoots, Aloha, Ron

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These new transmitters are in some countries legal and in others not. Here in Bangkok I found from the same factory transmitters from 1.2, 2.4 and 5 GHz. And in different wattages. Anyway, 1,5 watts is always too much and always illegal. (But not in Thailand apparently).

I have a similar transmitter, 0,5 watts, also illegal and I found that the output can interfere with other electronic equipment, like monitors and recorders. Use good quality cables and shielding.

Works very well though.

 

That said, it´s not so much the output of the transmitter as the quality of the receiver that makes the final result/image. Most of the time you will use it in a range of 10 to 30 meters(100ft) and anything from 10 milliWatts can give a decent picture in the GHz range.

But for unobstructed line of sight over long distances(1 to 5 kms) you can try the 5GHz 1 watt!

 

And be VERY illegal!

 

Rob van Gelder, Bangkok, Thailand

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That said, it´s not so much the output of the transmitter as the quality of the receiver that makes the final result/image.

As Mr. Wolf Seeberg pointed out to me, it's the transmitter's antenna that can make all the difference. A little rubber duck ant. might be a 1/4 wave of the transmitting frequency. Double the length of the ant. and you effectively double the output strength of the transmitter. Go four times the length to a full wave and the signal is four times as strong. Of course it can be difficult to walk along with a rig with an 18" antenna poking out, but this does do dramatic things to your signal. It can even take a legal transmitter and match the strength of an illegal one--and still remain legal under FCC guidelines.

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Hi,

 

First off a full wave antenna at 2GHz is only 5.904 inches long so it is possible to have one without it getting horribly in the way. Unfortunately as frequency rises reflections become more of a problem.

 

Also in the UK at least fitting an out of spec, multiple-wavelength antenna can make a legal transmitter illegal; I would be very surprised if the FCC didn't have similar rules for exactly these reasons. It would presumably at least nullfy any certification, making it illegal to operate.

 

Phil

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