Receive Preamp question
"Rod Maupin" wrote in message
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I am wanting to buy some receive preamps and am wondering if I'm looking at
it the correct way. Here are two examples from two different
manufacturers, both for the same band.
#1) .55dB NF, 16dB gain
#2) .9dB NF, 20dB gain
So, do you go for more gain or less NF? Since this is for weak signal
VHF/UHF work, I would say go for less NF but you can tell me what you
think.
Normally you go for the lowest NF. The NF is set by the first amplifier and
it should have enough gain to overide the NF of the next stage. With too
much gain you could overload the receiver, but unless you are in an are with
lots of transmitters it is doubtful you will with 20 db of gain.
The gain can be madeup anywhere in the system but the NF is set by the first
stage and anything after that will not help if the receiver is anything much
to start with.
Unless you are in a quiet location and are mounting the preamps at the
antenna I doubt that you will notice much differance in actual use.
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