[R-390] RF IMD Problem SOLVED!

[David Wise]

> From: Philip B Atchley [mailto:ko6bb@juno.com]
>=20
> NEXT, out of desperation I changed the RF amplifier, 6DC6=20
> tube with one
> borrowed from Dons Receiver.  EUREKA!!! IMD totally gone AND=20
> the S meter
> moved from 80dB to fully pegged on my local station (as other R-390A's
> have done in the past)          =20
>=20
> What I DON'T understand is this.  These two tubes checked=20
> IDENTICALLY in
> the B& K emission tester, both checked IDENTICALLY for gain in my
> receiver at 21MHz.  Neither test shorted or gassy!  RF GAIN=20

I have no diagnosis for you, Phil, but I hope you
keep that tube around so others on the list can
play with it.  I'd love to know what it's doing.

73,
Dave Wise