[doktar]

After completing my build, I tested voltages, they are all within spec.
 
When I try to calibrate,  Step 5- I only get about 15-16V max when it should be 20V

Then in step 6- I get 3 gain reduction LEDS on with all 3 trimmers all the way down (CCW) and cannot adjust to only 1 LED (-3)

Gone through the proceedure twice and same results.

Unit sounds as it should. 

[JPK]

Step 5- I only get about 15-16V max when it should be 20V
How many AC Volts max (against 0V) do you get on TP4 and TP5? (should be 11-12VAC)

Then in step 6- I get 3 gain reduction LEDS on with all 3 trimmers all the way down (CCW) and cannot adjust to only 1 LED (-3)
With PEAK at 0 What DC voltage do you get on TP8? (should be 0V).

[doktar]

After repeating, Im now getting about 23V max in step 5. So good there

Step 6 - with peak at 0 - there is 0v AC/DC on TP5.
  With peak adjusted to 10.6V - i get only -3 LED illuminated, but can adjust because all trimmers are down.
  With peak at 1.5, All LEDS are illuminated.  Still no adjustment.
   I'm closer now, but seems like slightly higher GR meter readings.  The -20 illuminates around 2.2 V