Wrong voltage on speedball big board [resolved]

[illusineer]

What about OA? It doesn't give any reading while the other one did give a reading on my meter.

[Paul Birkeland]

One side is reading 4,500,000 ohms and the other side is reading so high your meter can't determine what it is.

The manual says OA and OB on the big board should be several hundred thousand ohms at minimum.

I'm not seeing what the issue is here, I would move on to checking the voltages.

[illusineer]

OA - 120
OB - 221
G - 0
B+ 246

[Paul Birkeland]

Let's go back to pictures of the bottom of the board...

[illusineer]

Trying my best lol, this pcb soldering stuff isn't as easy as the stripping wires and soldering them to terminals sticking up ig...

[Paul Birkeland]

Can you send me a link to the solder and soldering iron you're using?

[illusineer]

I've been using this 60/40 rosin core radioshack solder that's been lying around in my garage forever throughout the whole amp, as for irons I've used this bluepoint soldering gun for about 95% of the time except for just recently with the pcbs I started using this weller iron (I like the soldering gun better).

[Paul Birkeland]

I would use the gun on your board.  You can leave the LED joints alone, but use the gun on everything else. 

[illusineer]

OK, reflowed with the gun put the board on again, resistance check, meter didn't read anything, voltage check

OA - 117
OB - 220
G - 0
B+ -226

[Paul Birkeland]

Well, at this point I would suggest sending it in for repair and I can fit a new board on it for you, or you can e-mail replacementparts to ask for a new board, or you can pull the LEDs and the two transistors on the bit that's not conducting and replace them.

Board rework isn't super easy though.

It's moderately probable that the big lump of solder that I saw bridging the connections on one of the LEDs would've required enough heat to melt the LED itself, and it may be damaged.  Some meters have a diode check setting that can allow you to measure them, and they should show about 1.57V in one direction and nothing in the other.

[illusineer]

My meter does seem to have a diode check, not sure how to work it though. I'm not super eager to spend more $ to send it back for repair tbh especially having been so close to having everything working 

[Paul Birkeland]

Well, you can get some solder braid and wick the solder out of those joints.  I would start with two new LEDs, then see what the results are before yanking out the transistors.

[illusineer]

I went ahead and replaced the big board and everything on it with new parts, did the tests and everything works now. Thanks