I manage a EMC test lab in the Seattle area. Typically we place a LNA pre-amp
at the DRG Horn we use for Radiated RF Emissions measurements above 1GHz. Below
1Ghz, we place a pre-amp at our measurement receiver - not the antenna.
Assuming a ham is using properly terminated double shielded CATV 75 ohm coax
for the RX antenna, the insertion loss of the coax should be less than 2db for
a 200 ft run. I find it hard to believe a ham would be able to "hear" the
difference between pre-amp locations during real live operating conditions. If
a ham wants to further improve the noise figure of their LNA, they would be
well served by placing a bandpass filter, for the band of interest, at the
front end of the pre-amp. Vy 73 de KO7I Sent from my Galaxy
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