Laney TT50H No Outout

[g1]

Is it R15 or R13 that is burnt, I was thinking from looking at the board that it went from left to right 11,13,15,17?

Yes, R13 is the burnt one, I was just going by memory and got it wrong.

[ca7922303]

See if you can de-solder pin14 of U2, til the pin moves freely and is no longer touching the pad. Be careful as the traces can be easily damaged and are thru-hole because it is double sided board. Then re-check that resistance of U6 pin3 pad to ground.
If you have very fine side cutters, I would just sacrifice U2 anyway. It's a lot easier to remove the pins if you snip them all and then desolder them one at a time pulling them out with needlenose. We know U2 took a hit because that resistor R15 is fried. And you also need to replace that regulator U6.
So that's U2, U6, and R15 to replace.

I'm noticing that U2 pins 13 & 14 pads read (0.0ohms) and both read (37 ohms) to ground? Should I cut pin#13, then remeasure U6 pin#3 pad to ground?

[g1]

Try disconnecting the ribbon cable instead. Then re-measure at U6 pin3 pad.

[ca7922303]

Try disconnecting the ribbon cable instead. Then re-measure at U6 pin3 pad.

Midi board ribbon cable disconnected, U6 pin #3 pad to ground(37.5 ohms).

[g1]

Can you post pics of U2 from top and bottom of board and showing pin14 snipped.
And double check that U2 pin13 still measures 39 ohms to ground.

[ca7922303]

Can you post pics of U2 from top and bottom of board and showing pin14 snipped.
And double check that U2 pin13 still measures 39 ohms to ground.

U2 pin#13 to ground (37.5ohms)

[g1]

Sorry, I had no idea that u2 was socketed. If someone tells you to cut an IC pin and it's in a socket, just pop the IC out of it's socket. (careful of static, ground yourself before you do it)
So where exactly did you cut the pin, at the socket or at the IC?

[ca7922303]

Sorry, I had no idea that u2 was socketed. If someone tells you to cut an IC pin and it's in a socket, just pop the IC out of it's socket. (careful of static, ground yourself before you do it)
So where exactly did you cut the pin, at the socket or at the IC?

U2 does not have a socket. I'll point to leg I cut in photo attached.

[g1]

Ok, I guess what I saw was U4 in the socket.
We had been talking about U6 being removed from the circuit. In the picture it is not.
Is that a current picture? If so, remove U6 and recheck resistance from pin3 pad to ground.

[ca7922303]

Ok, I guess what I saw was U4 in the socket.
We had been talking about U6 being removed from the circuit. In the picture it is not.
Is that a current picture? If so, remove U6 and recheck resistance from pin3 pad to ground.

U6 is still in place, but the legs have been lifted out of the holes, not touching the pads. U6 pin #3 pad to ground is currently (37.5 ohms).

[g1]

In your pictures pin1 is out of the hole but pin3 looks like it is not. That is why I am double checking.

[ca7922303]

Did you notice that I no longer have DC voltage to R43 on main board. What once was 442 vdc is now gone. There is 6.5vac to V1-V6 pins 9-5. Didn't know if anyone noticed that when I posted it post #209.

[ca7922303]

In your pictures pin1 is out of the hole but pin3 looks like it is not. That is why I am double checking.

Yeah, I checked it again and there all out of the holes.

[g1]

Did you notice that I no longer have DC voltage to R43 on main board. What once was 442 vdc is now gone. There is 6.5vac to V1-V6 pins 9-5. Didn't know if anyone noticed that when I posted it post #209.

Yeah, I know that and it can be dealt with later. The HT fuse is blown and it looks like one of the wires that connects to HT spade lug is probably burnt at it's connector. So that lug will need to be resoldered and the connector on the wire may need replacing.

Also see a switch that has been de-soldered in post #232. Which switch is that? Why is it de-soldered?

[ca7922303]

Yeah, I know that and it can be dealt with later. The HT fuse is blown and it looks like one of the wires that connects to HT spade lug is probably burnt at it's connector. So that lug will need to be resoldered and the connector on the wire may need replacing.

Also see a switch that has been de-soldered in post #232. Which switch is that? Why is it de-soldered?

Can you point to it somehow. I'm not seeing what is desoldered? Thanks.