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

Jose Tent

Don VE3IDS, 

  • 10k resistors, R39&40. =    10k confirmed.  solder continuity good.
  • 12 volt side of R40, =       11.9v
  • the junction of R39&40 =   3.32v
  • ground side of R39. =      zero
          I believe everything looks good here.   Thanks for the advise about clipping the top wire! Very helpful. 

  • R38 is 120k.  (Took it off the board and confirmed)
  • C22  .....not sure... (no equipment to properly test) 
  • IC10..... not sure....(no equipment to properly test) 

After I checked the above I stared at the circuit diagram for about an hour. and marked where the wrong voltage was being detected.  I also looked up specs on LM4562IC.  I didn't have any revelations, but I'm really starting to understand a lot about this circuit.  

I'm really tempted to buy an oscilloscope so I can trace the tone through the circuit. it's only 38$.  I figured the knowlege that I pickup going through the circuit with that would be worth it. 

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