On 9 Oct 2003 16:58:37 -0700, Tony Angerame wrote:
Back in 1977 there was a circuit published widely that claimed to
correct drift in a vfo by sampling the output, downconverting it,
comparing it with a crystal oscillator then correcting a varicap in
the vfo. Has anyone ever tried this? How well did it work? This
circuit, if it works, could be resurrected and bring a lot of the
older Boatanchor Rigs back on the air. It was called an FLL or
Frequency Locked Loop and was not very complicated.

Known colloquially as a "Huff and Puff" stabilizer of which PA0KSBs
one is an improved version. There was a simplified version of
PA0KSBs circuit published by G3DXZ, and a faster one by G7IXH.
They were discussed at length in the Radio Society of Great Britains
magazine "Radcom" in 1996 and 97, but that's probably not much help
to you. I believe that G7IXHs version was published in QEX in 1998
if that helps.
--
Cheers,
Stan Barr stanb .at. dial .dot. pipex .dot. com
(Remove any digits from the addresses when mailing me.)

The future was never like this!