"xpyttl" wrote in message
...
Huh? Yes, he is well into RF and construction techniques will be different.
But while there are advantages to air-coil cores, their use in recievers
went out with hollow state detectors.

I think that Coilcraft, API-Delavan, Pulse, etc. would be surprised to hear
them. Although I'd grant you that you don't typically find many air coils in
mass-market consumer electronics anymore, they're still used all over the
place in industrial and military design... where I work we buy tens of
thousands of the things every year for radio receivers!

Plenty of articles appearing in QEX and on-line also use air-core coils, since
it's a pretty fast and you can, of course, get whatever value you want with no
"minimum purchase" quantities.

---Joel Kolstad