Re: [help] Only noise being seen while IQ balance / phase lo / phase hi.


Don VE3IDS
 

Jose
If you clip the top lead of R37, that should separate R37 and C22 so you can do resistance checks of both without disturbing the board joints at this time. The cap should have infinite resistance. 

Don ve3ids


On Sun., May 31, 2020, 9:06 p.m. Jose Tent, <ksaito2@...> wrote:
Mutimeter:
    I'm using a 10030S Southwire digital multimeter.  Cheap, but not the absolute bottom of the barrel either.   

R37 Voltage REDUX:
I rechecked the voltage on R37 today again.   Well, the voltage on the top connected to IC10 Pin 5 is always higher by a bit through the swing of the volume pot. 
   Voltage top of R37 (IC10 pin 5) :     0.93v (@low Vol)    / 2.36v (@med Vol)    / 2.98v (Full vol) 
   Voltage bottom of R37 (C22)     :      0.8 V                    /  1.72v                     /   2.47v

Q7
I checked Q7 confirmed correct insertation.  Soldering looks good as far as I can see without any soldering whiskers. But it's hard to see since it's under the Volume pot. 

C22:
Ajparent1 is the second person mentioning installing C22 incorrectly. C22 doesn't have polarity. It is installed at the correct place. 

----

SO I guess we seem to have concurence that C22 may be bad and to proceed with taking it out and measuring IC10 voltage per Alan's post ??
(I'd rather remove c22 than IC10, so that is kind of a good news among the bad news) 

BTW, I want to thank everyone for helping me.   This has been educational.  



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