In article .com,
Joe Analssandrini wrote:

My terminology may have been confusing and hard to understand. What I
meant was that the pitch of a sustained musical note will change while
using the Drake synchronous circuit. This happens when the signal is
subject to fading and the circuit attempts to maintain lock. It is most
noticeable on musical shows, naturally. The note sounds as though it's
being lowered a semitone or sometimes even more - in other words, the
music sounds as if it's going a bit flat or "sour."

Sounds like there's a bit too much FMing of the "BFO" (local carrier
oscillator).

One bit of trivia I remember reading in an old QEX (I think). Some of the
hams who work with real narrowband modes, (the guy who did "Synchronous
CW", Pettit?), was working on a phase shift keyed narrowband mode and
had a very stable receiver that could output the phase of the signal
it was tuned to. He said that some of the shortwave broadcast signals
were not stable in phase. (My guess, the result of some of these high
effiency digital transmitters). In the short term, the carrier phase
danced all around. This would give a PLL with a relativly short time
constant filter that sort of symptom.

Feedback control systems (ie. the Phase Locked Loop) can be a real bitch.

In any case, it is my opinion that during actual listening, the AOR
AR7030 Plus' synchronous detection circuit is "superb" and the Drake
circuit is "merely" excellent.

Do you work as an advertising copy writer? Or work in some sort of
sales/marketing job? ;-)

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)