Re: QCX 40m Version 4 new build problem

James Daldry W4JED
 

Hi, Wes

IC10A is a zero-gain voltage follower. Pins 1, 2, and 3 should be at exactly the same voltage. Anything else means (a) you have a bad IC10 (HIGHLY unlikely) or (b) there is no connection between pins 1 and 2. Check it on the top side with an ohmmeter. Then resolder pins 1 and 2 anyway. Maybe cover the 2 with a single "blob" of solder.

73

Jim W4JED

On 12/18/19 1:21 PM, Wesley Matthews wrote:
Alan,

Thanks for sticking with me. I checked all the parts again, re-soldered some questionable joints, and even wiggled every part on the board with a ceramic screw driver. Pin 1 on IC10, using an external DVM, is still 13v.
R21, R35 all read correct. I double checked the AF Gain pot also.

Could there be a short in T1 that might wreak havoc with audio gain?

Wes
WM7WM
--
72/73

Wes
WM7WM

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