Hi Milt,
> I would be interested in the particulars of your negative experience with
> the ARR GaAsFET preamplifiers.
I just measured an AR2.
Output power 1 dB gain compression -11dBm
NF .6 dB
gain:
1.8......... 24.31 dB
7.0..........15.15
30............13.48
50.............13.85
400............7.98
This is a "1.8 to 2 MHz" model. I didn't measure LF cutoff, but it
wasn't starting to roll-off much at 1 MHz!!! People might get the
false impression this amp rejects out of band signals a worthwhile
amount!
This amplifier would be good on a small resonant loop antenna, but
would be worthless on anything large and/or broad-banded. The
accumulation of signals from some low frequency to 400 MHz and
higher would drive this thing crazy, it also gain compresses at a
pretty low level.
Even a four dB NF is plenty on 160, unless the antenna is super
small and you are in a quiet location. I have problems with
overload (without filters) on my Beverages using preamplifiers that
compress at +10 dBm output! I can't imagine using this amplifier
on anything but a small resonant loop.
73, Tom W8JI
w8ji@contesting.com
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