I'm guessing here as I'm not sure about your amp at all, but would suspect
that it was designed for a 5 watt stock output radio. If you are indeed
putting out over 20 watts (all where you want it; no guarantees here), you
are likely overdriving it. Somehow, the units have to work together. Kinda
like you go to the store and want the fastest hard drive they have in stock.
Gee, kinda expensive, but it is guaranteed to be the "fastest". So you get
home, open up your computer (with an IDE interface) and guess what? IDE
drives aren't the fastest drive and you now own an ultra scsi hard drive
that won't work with your computer. You got what you asked for, but it is
not compatible with your system. I am also not familiar if you are using
the radio/amp as a base; if so, it is possible that you are demanding more
from the amp than the power supply can provide; in this case, a hum on the
DC to the amp would result as it falls out of regulation 120 times per
second and very possibly results in a hum on your signal. Many folks would
be far better served looking for a good antenna rather than an amp. Would
you believe that a vertical antenna mounted low (say on top of a ranch
house) over "normal" ground can result in a 6 dB loss compared to the same
antenna mounted two wavelengths above ground? This can well be true, at
least as far as the signal strength put towards the horizon (which is where
you want it) is concerned! Also, 5/8 wave antennas can produce real gain as
opposed to a 1/4 wave whip. Combine going from a 1/4 wave ground plane on
your roof to a 5/8 on a tower and you could come up with quite a few dB
difference - a difference approaching adding that amp (and very possibly at
a lower cost). It will also improve your reception.

This is somewhat conjecture on my part, however. Perhaps someone else can
give you some ideas.


73 from Rochester, NY
Jim




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