Line 6 DL4 power problem

[dustartist]

That is what I thought. And that led to the solution. The power jack is soldered to the PCB on the bottom of the board, but it is a two sided PCB. The jack solders on the bottom, but the ground trace goes back up to the top of the board through a via. That is where the connection was broken, somewhere in the via. You cant see or solder to the top pad because the jack is on top of it. I jumpered the jack ground connection to the ground plane and it is working again. Thanks!!!

[Jazz P Bass]

Great find on the cracked via.
Through hole connections are actually plated, like a tube, which connects the top pad to the lower pad.
If the pad gets cracked you can lose that connection.

[geektard]

I have a frequency from the regulator I installed in so I better do a proper job and add a couple of capacitors. I'll post a diagram when I have it working properly.

[beedoola]

hopefully someone might offer some insight.

I bought a DL-4 dead and tested the power section - all seems to be good. I cleaned the main/removable chip's contacts with some deoxit as well as the socket pins. I was able to get the DL-4 for power - relay clicks, and the 2 left LEDS blink and then the 2 right LEDs flash but the boot up gets stuck on the 2 latter LEDs. They just stay lit for about 10-15 seconds before they got off and the relay clicks again.

Any pointers?

[Jazz P Bass]

C 40 is the boot up delay. (1000uf)
Remove it I see if that helps.
If it does help, replace it with a new one.

[beedoola]

C 40 is the boot up delay. (1000uf)
Remove it I see if that helps.
If it does help, replace it with a new one.

remove it and jumper the pads or just remove it leaving the pads alone?

[dustartist]

OK, almost 3 years later and I'm back with another DL4 that will not power up. U14 was pretty hot and giving wrong voltages, so I replaced it and most of the caps and resistors around it, but I'm still not getting the right voltages. It's not getting hot, which I suppose is a good sign, but i just noticed the DSP chip is pretty warm. There seem to be some fluctuations in the current draw as well. Not sure why I can't get the correct voltages out of the MAX887, I have 6V at pin 8 going in, but only 2.4V on pin 7 which should be at 3.3V. Scratching my head....