Voltage check question. 10 and 44-45 [resolved]

[Paul Birkeland]

You can pull the cap out of the Reduction completely with the new resistor installed to see if that changes anything.

If you hit the cap and burn it enough with the soldering iron, I'm sure it could be damaged, but this is pretty rare.

[canonken]

New resistor on the way.

Before I solder it back in, is there ANYTHING else that I should check or could cause this?

Thanks,

Ken

[canonken]

AAAGGGGHHHH!!!

Put in the new resistor and still reading 80 volts on 10.

Is there anything else (the chain of components between 10 and 15) that could cause this issue?  As you know, some of these parts are hidden when the 4 caps are installed.  If it is electronically impossible for it to NOT be something else, that would help.

I'm not sure what else to try.  I don't know how I could assemble the rest of the kit correctly, but continue to fail at reflowing 10 and 11, then removing, replacing the resistor.  I am not saying I am skilled, but I feel redid the connections enough it would work from dumb luck.

Is there something I can do to rule out the .47uF capacitor as the culprit?

Thanks!

[Paul Birkeland]

Remove the 0.47uF cap from that side of the amp and recheck the voltage.

[canonken]

Thanks for the reply.

Won't that mean 0V on 10 by default - as the only way I am getting 80V to 10 is via the 80V on 2?  I get 73V on 13-15 (not 80V).

Or are you asking to remove one of the two leads from the cap (I can lift it out of the way, make sure I don't touch it) - and recheck voltage on 1-16 (the entire affected side)?

[Paul Birkeland]

Take the 0.47uF cap out of the amp and recheck the voltage on terminal 10.

[canonken]

Hi,

I removed the .47uF cap completly.  10 reads 0 volts.

If I do a continuity check on the cap, it beeps constantly and shows a impedance of 0.1 to 0.5 ohms.

I happen to have a mis-shipped (same line of Dayton as the .47uf) .1uF cap, and it immediately shows OL and no beep when read with the same meter.

Thanks again for your support.

[Paul Birkeland]

I would toss in a replacement cap.  Is there any physical damage to the cap? 

[canonken]

Hi Paul,

There is no damage I can see, I am happy to send you images or the cap.

With the cap removed, are there any other checks I should perform (should all of the other voltages read the same, or does the cap being out impact anything else up or downstream)?

I will email for a new one.

Thanks for the quick reply.

[Paul Birkeland]

If the cap is showing a low resistance measurement out of circuit, the cap needs to be replaced.

[canonken]

Replacement cap arrived today, soldered it in, did a final voltage check and...

Works perfectly!  Have a record playing as I type.

It was that .47uF cap causing all of the drama

Appreciate the support.