Most of the amplifiers such as the ARR (Advanced Receiver Research) are
over kill on the amplifier gain i.e. 24 db, however the Motorola RF
preamplifier, Models TLD8421B and TLD8422B have only a 10 db gain. The
latter has a two stage aperture coupled helical resonator and a tuned
output stage to match the receiver input. This little guy has very good
spurious and image rejection, selectivity, and intermodulation
characteristics. We use it at our shared (two club receivers) sites
with a four port splitter. Net output is 2 db. We use the ARR with a
window filter to feed the two port and two four port splitters with gain
left over. This extra gain is padded down to prevent any of the radios
at the output from being overloaded, and we have lots of different
receivers at the splitter outputs.
The pad suggested in other posts after the preamplifier makes a lot of
sense (not desense).
Ciao, Tony
Joe wrote:
> Actually, try somewhere between .5 and 2dB BEFORE the preamp, you might be
> surprised that effective sensitivity will go UP an d desense will go DOWN.
>
> Joe
>
> ---- Dave Baughn <[EMAIL PROTECTED]> wrote:
>
> =============
>
> Try adding a 10 dB pad AFTER the preamp. Should not affect sensitivity but
> may help your desense. AAR preamp has more gain than necessary.
>
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> Yahoo! Groups Links
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