There were a few posts a week or so ago about using the 2N5109 as a
preamp for Beverage and other receive antennas.
October, 1976 issue of HAM RADIO MAGAZINE has a schematic with parts
list for such a unit. This design is broadband, and I would think it
would be very desireable to place a filter and tuned circuit at the
input.
The specs are very interesting: 3 db NF @ 200 mhz; gain of 11 db from
50-216 mhz; and cross-modulation distortion of -70db. Used in earlier
TV preamps, this device is still available for very low cost.
For a bandpass filter which can be used ahead of this preamp, refer to a
good article by W7ZOI in HAM RADIO MAGAZINE, February, 1975.
Bill, VE3CSK
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