Re: K5BCQ click fix 2nd generation installed #ubitx


OK, I am stumped and I could use some help. For context, the issue is no Audio at all when powered on ANT attached or not.

I annotated this drawing to match my pictures.

Here's what I've tested all but the TX test was without mic attached:
  1. Rework
    • I resoldered a few wires that didn't look great.
    • I cleaned up a dropped blob of solder that was all over C250 and R251 on the main board. (oops)
      Ultimately, I had to pull C250 off the board, clean the solder off the board and reattach. The solder caps came off C250. I rebedded it in solder on the pads as best I could. It is firmly attached and continuity around it is correct. <<-- This might be it. Not sure.
    • I cleaned the board and main board anywhere I did work with rubbing alcohol and a q-tip
  2. I replaced my TDA2822 just to see and it had no change.
  3. General Continuity Tests
    • I have continuity from the outboard end of the wire (from the main board) to the next component on the add-on board (i.e., across the next trace) as follows:
      • Blue  to R5
      • Brown to R3
      • Black to C1
      • Purple to Bottom right leg of Q3 (as in drawing above)
      • Yellow to R2
      • Orange to top of Q2
    • My trace breaks on the main board are all good. No continuity across those.
    • My jumper wires at the breaks are good. Continuity across those tested across and not on the jumper wires.
  4. Power Tests (RX)
    • I DO NOT see any voltage on Blue wire to the Black wire (GND) on the board. This makes sense .. its on the TX side.
    • I DO see 12v from on the Brown wire to Black wire (GND) on the board. This is the RX side so again, that makes sense.
  5. TX Tests
    • PTT does enable TX on the display
    • PTT turns on 12V on the Blue TX wire (see above)
    • PTT turns off 12V on Brown RX wire (see above) 
  6. Speakers
    • I tested with a mono speaker that I've used before
    • I've tested with a stereo headphone that I've used before

My fear is that I've messed up the capacitors (that's what those brown things are right?) at C250, C50 and C63.

Am I correct in my sizing of these from the V3 schematic (
C50 & C63 - 1u
C250 = .1u

Am I also correct that C50 and C63 are polarized? I could have screwed that up when I desoldered them, dropped them 300 times before I barely stood them on end and tombstoned them. ;)

I'm stumped and could definitely use an Elmer.
Patrick W7PEA

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