1. Calibrate GAIN and CV MOD Controls
Larry Hendry has a detailed procedure for adjusting the VCA so that the GAIN and CV MOD pots will match up with the front panel markings. I performed this procedure on two MOTM-110s and came up with the following values for R1, R5, and R26:
 
	
		| 
		 | 
		
			VCA #1
		 | 
		
			VCA #2
		 | 
	 
	
		| 
			R1
		 | 
		
			48.2K
		 | 
		
			49.1K
		 | 
	 
	
		| 
			R5
		 | 
		
			57.5K
		 | 
		
			55.2K
		 | 
	 
	
		| 
			R26
		 | 
		
			38.4K
		 | 
		
			40.6K
		 | 
	 
 
 
I used 47K resistors for R1, 56K resistors for R5, and 39K resistors for R26 by measuring with a DVM and choosing the closest match from my stock of 5% resistors.
Larry Hendry's MOTM-110 tuneup procedure.
 
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