Doug:

To add to what Roy says, I have been able to only get 20 to 25 dB total
attenuation at VHF with a single pot. And, the effect he overlooked is that
unless you use the exact same electrical length cables, the attenuation will
be different for every other configuration. So, if you develop a feel for
knob position vs distance while hunting, it will change if you don't use
exactly the same cables each time.

Haunt the swapfests and evilbay for attenuators. I have seen HP units go
pretty cheap. Be careful of Kay brand, as they are known to have bad
switches when they get old. If you want to learn the innards, that is a
good way, rebuilding a Kay.

I think there was an old HP spectrum analyzer main frame with a model number
like 853 which you can't give away these days. But, it has a nice rotary
attenuator in it, if you find one. Then you just have to dispose of the
rest of the box.

--
Crazy George
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