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Old 28th April 2013, 04:01 PM   #41
Mr. dB is offline Mr. dB  United States
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Also, if the Solder Wick isn't grabbing it, sometimes it helps to add a touch more solder to the problem first, even if it seems counterintuitive at first.
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Old 28th April 2013, 05:44 PM   #42
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Sometimes, if you just need to open up a hole, you can insert a toothpick to leave a hole after melting the solder. Solder will not stick to the toothpick.
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Old 2nd May 2013, 02:59 AM   #43
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Thanks, all. I am sorry I didn't try adding a bit more solder, as that makes sense--I was left with a small amount in the hole I couldn't wick out. Regardless, got a new set of micro drill bits (mine walked) and drilled it out. And finished it up. And plugged it in to the power supply...

On the positive side, no fire, no smoke. The red led's went on. I wasn't sure what to do, so I tested the voltage as recommended on the pcb near the pot. I put the red lead on the place near the pot, black on the ground in. I got an initial reading of around 5v, but it was not stable, it fluctuated across a large spectrum, steadily dropping well below zero, than higher. The led's would periodically go on for a bit, then off for a while. This seems bad. Can anyone offer suggestions? Not sure what to do.

Thanks!
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Old 2nd May 2013, 03:12 AM   #44
6L6 is online now 6L6  United States
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Short the inputs. Keep the outputs open.

Put the meter (DC volts) on the test pad and adjust it (as best you can) to zero.

If that point calms down, then probe around to the other points on the boards and record your voltages.

Use this schematic -

Click the image to open in full size.
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File Type: pdf Pearl2Votages.pdf (67.0 KB, 299 views)
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Old 2nd May 2013, 12:50 PM   #45
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Quote:
Originally Posted by 6L6 View Post
Short the inputs. Keep the outputs open.

Put the meter (DC volts) on the test pad and adjust it (as best you can) to zero.

If that point calms down, then probe around to the other points on the boards and record your voltages.

Use this schematic -

Click the image to open in full size.
Hate to ask, but can you explain how to short the inputs, keep the outputs open? And, should I put one lead on the test pad and one on ground? Thanks.
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Old 2nd May 2013, 03:49 PM   #46
6L6 is online now 6L6  United States
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Keeping the outputs open is easy - don't connect them to anything.

Shorting the inputs is also easy, take a clip lead and connect the input hot to the ground at the rca. Or take some old junky interconnects, cut most of the wire off, leaving 2 inch or so, strip and connect the wires together so the rca plug connects the hot to ground.

Yes, black on GND (at the PSU entry is fine.) probe with the red.
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Old 3rd May 2013, 12:34 AM   #47
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Ok, it is now interesting. Sorry to use this board for troubleshooting, but...

Hooked it up again. Wired as recommended above, started checking voltages. To start wit what I know, I checked past r3 and r4, got just below 24v as expected, did same with r31 and r33, got -24v on one, -31 on the other. This had happened earlier, but I thought I had fixed it when I cleaned up the solder. So I redid the solder around the voltage regulator, hooked it up again. Smoke! Resistors 30 and 32 on both boards smoked and died. I checked the voltage at the jack and it was +-34 as expected. I will replace the resistors, but don't want to just burn up another four. Any ideas?
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Old 3rd May 2013, 12:44 AM   #48
6L6 is online now 6L6  United States
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Use a light bulb lead next time...

You have a short somewhere, and/or you fried the regulator.

Pics please.
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Old 3rd May 2013, 01:02 AM   #49
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Time to build the light bulb tester, I suppose...or a bit late.

Here are the pics, not sure what you are looking for. Both boards were plugged in, both sets of resistors fried before the negative voltage regulator fried. No good reason for having both plugged in...

For what itis worth, my guess is that in"fixing" the solder for the regulator I created a short, which caused a surge and fried the resistors. In which case I would need to find out if I killed the regulator/s.
Attached Images
File Type: jpg photo(3).jpg (696.4 KB, 59 views)
File Type: jpg photo(4).jpg (605.8 KB, 59 views)

Last edited by jhsjhs99; 3rd May 2013 at 01:08 AM.
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Old 3rd May 2013, 01:50 AM   #50
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Check the polarity of the voltage coming into the board. If you had v+ and v- reversed, you would burn out those resistors. From experience. I burned mine a lot better than that.
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