Madbean Kraken issues

Started by DK1, February 05, 2017, 06:11:52 PM

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DK1

So, I'm vero building a Kraken, and I'm getting nothing but ticking out of it. I've checked components, cuts, and links, and audio probed it, but it's even ticking at the input, so that's not being very helpful. I basically lose all signal past c3/c4 (33n/47n). After that, it's just ticking. The pots and switch definitely have an effect. They vary the speed and pitch of the ticking.  I've also tried different ics, just in case. I don't trust my ca3080s completely, since they are eBay specials. Any thoughts?

Vero build from: http://tagboardeffects.blogspot.com/2013/11/madbean-kraken.html?m=1

Schematic:http://madbeanpedals.com/projects/Kraken/Kraken.pdf

Voltages 

9.06v in

ic1 (ca3080)
1:80mv
2:4.8v
3:4.8v
4:0v
5:96mv
6:6.9v
7:9v
8:8.3v

ic2 (lm1458)
1:5v
2:4.8v
3:4.8v
4:0
5:4.8v
6:6.9v
7:1.5v
8:9v

Q1 (2n5089)
C:9v
B:4.7v
E:4.15v

Q2 (2n5087)
C:~70mv
B:4v
E:4.6v

Q3 (2n5089)
C:9v
B:5.4v
E:4.8v

The build doc/schematic has voltages, but I'm pretty sure they have ic1 and ic2 labeled backwards. Otherwise, some of them don't make sense. I'm not sure how I have 8v on ic1-8. It's not connected to anything. Also can't figure out how my pins 6/7 on ic2 are so far off from the build doc.

Thank you

PRR

Leak in or around C11. Lift one leg and see what changes.

Look again for a near-short on LM3080 pin 5.

Where did you get the LM3080?
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DK1

Quote from: PRR on February 05, 2017, 09:06:32 PM
Leak in or around C11. Lift one leg and see what changes.

Look again for a near-short on LM3080 pin 5.

Where did you get the LM3080?

OK, I resoldered that cap, and re knifed all the vero around pin 5. Same thing, sounds like a helicopter.

The Ca3080s are from eBay, the lm1458s are from Tayda.

Thank you for the input.

PRR

We have seen a large number of "fake" LM3080. Often pin 5 goes much higher than should be possible. Yours has pin 5 way lower than it should be. Inconclusive.

Small Bear is one source of good LM3080. You pay for Steve's diligence in vetting his sources and testing his chips. But it isn't real expensive.
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reddesert

I built a Kraken on a Madbean PCB, and rather than take chances with dodgy CA 3080's, I used this daughterboard to adapt an LM13700: http://tagboardeffects.blogspot.com/2012/10/emma-transmorgrifier.html . It works well.  Smallbear ICs would surely be fine, I had an LM13700 already; they are easy to get.

DK1

Quote from: reddesert on February 06, 2017, 03:28:23 AM
I built a Kraken on a Madbean PCB, and rather than take chances with dodgy CA 3080's, I used this daughterboard to adapt an LM13700: http://tagboardeffects.blogspot.com/2012/10/emma-transmorgrifier.html . It works well.  Smallbear ICs would surely be fine, I had an LM13700 already; they are easy to get.

Good point. I was actually thinking the exact same thing last night when trying to go to sleep. I already have a daughter-board made and some LM13700s laying around from a past project. I just didn't remember until close to midnight. So, I should be able to check tonight after work.

Thank you.

DK1

My replacement ca3080s came. Looks like that was the problem. Circuit worked fine. That's my second bad batch of ebay chips... Guess I'll be paying up for verified sources from now on.

strassercaster

which seller sent the bad chips/ Good Module sent me some that didnt work then when i got a refund they banned me. BAD SELLER. I went with someone on aliexpress for the next decent batch