In article , Neil
Preston wrote:

I want to be able to send a UHF TV signal (400-800 MHz) from one end of the
house to the other. I have a UHF digital PLL modulator with an output level
of 7dBmV minimum, and would like to use it to feed a small linear 100 mW
"power" amp to a 1/4 wave whip.

I don't think I'll find such a critter very easily, (if at all) so I would
like some suggestions as to how I might find resources to build one. (Of
course, a pre-designed schematic and PCB layout would be ideal!)

Anyone have any suggestions as to where to start? (Besides Google... BTDT.)

Neil Preston, CET


I'll take a wild ass guess that you don't want the signal propagating
equally in all directions, but that you have a particular signal path
in mind.

Putting something as simple as a corner reflector (or a parabolic
reflector) behind the transmitting antenna can give you an effective 10
to 12 dB signal increase. Focusing the receive antenna helps as well.
If you build a pair of reflectors, your total investment will be on the
order of 75 cents. Look at freeantennas.com for templates you can
scale for your frequency. Reflectors let you focus the rf energy where
you want it.

If you *really* want to use an amplifier, search ebay for minicircuits.
They make prepackaged rf amplifiers, along with a lot of other rf
goodies. But you're going to have to adapt your gadget and antenna
system to interconnect with 50 ohm lines and SMA connectors. And
somehow I doubt the output of the transmitter is spectrally pure. It's
bound to have *some* filtering in it (one would hope), but when you put
it into a very wideband amplifier (such as the MiniCircuits ZFL-1000GH)
that amp will amplify *ALL* the signal -- fundamental, spurs,
harmonics, you name it. And do you know what the output level of your
transmitter is (into a 50 ohm load)? You need to know that to properly
select the amplifier.

Try the reflector aproach first.

--
Namaste--