It is my understanding that 2nd and 3rd order Intercept points
(ICP2in and ICP3in) are an important characteristics for an amplifier used
for MW frequencies. I suspect the same is true on 160 meters, partly because
of the MW BCB signals.
The Nov 21 1994 issue of DXnews has an article titled "Ultralinear
2N5109 and=20 2N3053 Amplifiers". Back issues or copies of the article may still
be available from the NRC. http://www.nrcdxas.org/catalog/ Articles A87, A88
These amplifiers known as common base transformer feedback (CBTF) or
common base noiseless feedback (CBNF) were first described in May, 1976
MICROWAVE JOURNAL. This amplifier in the push/pull configuration can have an
ICP2in greater than 95dbm and ICP3in of 27dbm to 34dbm with 12db of gain. Gain
is changed by using different turns ratios on the feedback transformer.
I have not found any other information on these amps, if anyone has
more info I would like to know.
Mike Knowlton
Panama City Fl.
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