Hairball 1176 - Discrete Meter Circuit/Null Adjust **GR Meter problem**

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jdier

Member
Joined
Feb 9, 2017
Messages
10
Very much a newbie to electronics, but completed my Hairball 1176.  Power Supply test perfect, completed build and Q Bias went great.

When I get to Discrete Meter Circuit/Null Adjust, I am unable to make the meter move at all.  It sits < 0/-20 

It does not appear that I have blown the meter as I can put test tone to the input, choose +4 or +8, and my input and output controls appear effect the meter the way I would expect.

Once I switch back to GR, the meter remains all the way left, just under 0/-20.

I pulled the FET Meter board and there does not appear to be any shorts.  (however, I did notice that there are three points unused marked "22" "GRN" and "BLK"

Any help would be greatly appreciated.

Jim
 
New Hairball 1176 rev. A
I can't complete calibration # 3 the Gain Reduction Meter Tracking Adjustment.
on step # 4  Set attack full CCW (off position). Set input control for +10dBu (2.44 VAC) at your output XLR. i only get 1.4 vac and i set input control all the way , and miter  dose not move in GR mode.
i ran some drums thru the comp and it sounds great,  miter works in +8 and +4 mode BUT NOT MOVING IN GR mode.
 

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