[Drake] R4B Oscillator Stability/diversity reception

[Ka9p@aol.com]

First of all thanks to everyone that responded with radios and parts for my 
R4B diversity receiver project.  It's up and running and alot of fun. I was 
really pleased with the response of reasonably priced stuff and not having to go 
swim in thE-Bay for them. 

As it turns out the simplest way to slave the pre-mix oscillators with no 
holes, no mods is to yank the 6HS6 pre-mixer from the slaved receiver and simply 
running a cable between the two "oscillator" jacks already on the chassis.  If 
you've got a pair and want to try diversity, this is a 5 minute, reversible 
way to get there and works just as well as other fooling around I won't 
embarass myself discussing here :)

Slaving the pre-mix oscillator without slaving the IF crystal oscillator or 
the 50 khz bfo has resulted in long term stability between the receivers of 
between near zero and about 20 hertz, which is fine for AM but sometimes a little 
much for SSB/cw.

What I'm wondering is whether anyone has a good guess as to which (or both) 
of these oscillators is the major source of the drift, as I'd like to take a 
step wise approach to slaving them with as little alteration of the radios as 
possible.  I am aware the C line has a 50 khz output jack, which makes me 
suspect the BFO, and that the IF crystals are color coded according to their 
temperature coefficient, which makes me suspect that as well (I have a "C" and a 
"R").

If anyone has any ideas on this, or the best way to slave those oscillators, 
I'd really appreciate hearing your thoughts.

Thanks, Scott