[QuadList] VR-1200 Capstan Oscillator Mod for Course and Fine Adjustment Pots

[Chill315 at aol.com]

VR-1200 B Series Inter-Sync 60 Hz Capstan Oscillator Modification
 

This was given to me by someone a long time ago.  It made life  simpler.
 
The capstan Oscillator is difficult to set and is critical for assemble  
edits.  It sets the free run speed for the capstan.  There is a simple  
modification that will provide the user with a course and fine adjustment pot  for 
the oscillator.
 
Remove Board 13 from the Inter-Sync.
 
Find R-78, the 625 Capstan Frequency adjustment.  
 
Lift the wire that connects the end of the pot to Q-12 Collector.   This is 
the end not connected to R-60, a 300K resistor.
 
Attach wire disconnected to the End of R-20 that is not connected to R-38,  
a 20K resistor.
 
Reinstall board
 

TEST and Setup
 
Center R-78
 
Adjust Capstan Oscillator using R-20.
 
>From now on only use R-78 for Capstan Frequency Adjustment unless pot is  
near the end of range.  Then re-center and set Oscillator with R-20.
 
R-20 is now the COURSE adjustment and R-78 is the FINE  adjustment.
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