Kraken Issues.

[steveyraff]

Hey guys.

So, back to a real headscratcher. I built this one recently: http://tagboardeffects.blogspot.co.uk/2013/11/madbean-kraken.html

Tried to be as meticulous as possible building it, but as sometimes happens, when I fired it up, I only got dry bypassed signal.

The LED's work fine (I added a second).

Its doing something similar to a previous envelope filter I built which didn't work at first. When you strum real hard, you can kind of hear a crackling signal trying to get through - more so when first powered up. Apart from that, its just total silence. The last time that happened on the previous build, I realised I had some wrong resister values, so it wasn't getting enough juice.

I've double and triple checked all values of all resistors and caps. I've checked every leg is soldered in correctly to the correct place. I've checked all holes and bridges. I've scored between all tracks to make sure there are no accidental solder bridges. I've double checked my offboard wiring. I'm just stumped now!

The only thing I can think of is the 3080 IC. I think it came from ebay, and when I took it out of its packaging, 3 legs on one side of it just fell off. To remedy this, I used a few resistor legs and soldered them on to where the broken legs should be. It looks fine, but it could be faulty now. I am pretty fast with my soldering, but maybe I overcooked the IC from both soldering the legs on, then soldering them into the board.

I haven't had a chance to test the IC with my multimeter yet, but I was just wondering would a faulty IC cause this kind of issue? Also, if I do test it, what sort of values should I expect to have for each pin?

Thanks in advanced for the help.

[Blitz Krieg]

3 legs on one side of it just fell off

ouch

[bluesdevil]

Would not trust that chip! If you don't want to chance getting another bad one from eBay, I've seen a layout for an adapter board using the 13700 chip in place of 3080.
EDIT: Here's the link:
http://effectslayouts.blogspot.com/2015/11/lm13700-to-ca3080-conversion-board.html

[steveyraff]

Would not trust that chip! If you don't want to chance getting another bad one from eBay, I've seen a layout for an adapter board using the 13700 chip in place of 3080.

I bought two new 3080s. I'll let you know if a replacement makes a difference!

[steveyraff]

Yep - it was the 3080. Got a replacement and all sounds sweet now.

Cheers all.