low intermod RF amplifiers for HF.
clifford wright wrote:
Good day!
Can anyone point me towards a good design for a good RF stage for my
home
brew HF receiver. I have no less than 6 others hams in my small town
and
one within 400 metres, so I need good strong signal performance.
10 to 15 dB gain would be ample, but I would like to have 50 Ohm
input and
output impeadances.
The receiver is an upconverter to 45MHz with a 15 kHz bandwidth xtal
filter followed by a downconverting mixer to either 9MHz or 10.7 MHz
with
separate IF strips.
Tuning is by a PA0KLT synthesiser.
I have been a bit out of touch lately and am not very up to date with
the
latest MOSFETS etc. The mixers use the 1992 Ulrich Rohde FET double
balanced mixer circuit.
The rest of the sytem was built back in the early 1990's but put to
one
side until a better frequency sythesiser was available.
Now it looks like the time to get things moving again!
Regards Cliff Wright ZL1BDA ex G3NIA.
Why do yo need more amplification in front of your receiver. It's
making more sense to use a tunable preselector.And putting the
amplification in the IF's.
Regards,
Jan PE1SBG
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