Variable selectivity?
"gareth" wrote in message
...
I'm in the process of making a retro RX, primarily because I've a junk box
going back
50 years and if I don't do something with the bits now, then the executor
of my will is likely to skip the lot.
I recently analysed the Sperry PWD dial from the HRO, and conceived of a
way to reproduce it, but without needing an internal toother ring.
However, my tastes have changed, and I'm now heading for an RX that is
similar in style to the Eddystone EA12.
But the one thing that I owe to the National design in my musings is the
possibility of
emulating the Catacomb from the NC100X RX, as the means of simplifying the
wiring of a bandswitch.
I was originally interested in the variable selectivity of the Eddystone,
and, indeed, have obtained
a photo of the innards of one of the variable IF transformers, but I think
that I'll do a coouple of ladder
filters based on modern practice, with both SSB and CW versions.
Once again, very interesting articles from you, thanks!
Gareth G4SDW
Let's go Beanie, let's go.
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