"garyr" wrote in message
...
I'm trying to build a 80/40 meter receiver and I'd like to be able to
switch the RF input between the two bandpass filters. This sort of thing
is
usually done with relays but I'd like to avoid that if possible. A
SN74CBT3306 would be ideal but I think the on-resistance would be too
high,
thought it's hard to tell from the data sheet. Are there other devices
that
would be suitable for this application? What do you think about using
2N7000's for this job?

The input and output capacitors of the double-tuned filters are 2200 &
2700
pF so the stray capacitance of the switching circuitry would not affect
the
response very much.

Thanks in advance
Hello
IMHO diodes switches are by far the way to go.
They have been used for years in TV tuners at UHF frequencies.
They are very small and allow to place the switch exactly where it should
be.
They can support power as in TX/RX or atténuator swithes.
Cmos IC's are used too in some SDR receivers but having to bring RF tracks
to a small SMD implies stray capacitance and inductance problems.



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