MadBeanPedals Kraken (Mutron Micro V) voltages?

[LucifersTrip]

I'm helping a friend build the Kraken (Mutron Micro V) with the MadBean pcb:

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


Finished soldering components (no subs) to the board & tested it unboxed. It worked, so took voltages.
Played for about an hour....

======================
Supply: 9.65
all 5's are approx and vary slightly, most ~ 5.1V

IC1 CA3080
1: 0
2: 5
3: 5
4: 0
5: 0.61
6: 5
7: 9.65
8: 0

IC2 LM1458
1: 5
2: 5
3: 5
4: 0
5: 5
6: 5
7: 5
8: 9.65

Q1
E: 4.5
B: 5
C: 9.65

Q2
E: 0.61
B: 5
C: 5

Q3
E: 5
B: 5.73
C: 9.65
======================

Unclipped (used alligator clips) the 100K delay pot to try the suggested 250K or 500K, clipped it back in and no quack at all. It's just a mild distortion and no pot has any effect. The hi/lo works. The voltages remain exactly the same.

Are the above close to what they should be (I don't see any troubleshooting voltages in the MadBean pdf)? If so, is it time to swap out the IC's?

The voltages someone posted on the MBP forum are similar with IC2-6 different and IC1-6 & 7 swapped (error):
http://www.madbeanpedals.com/forum/index.php?topic=14759.msg138244#msg138244

Btw, I did what Midwayair suggested:
http://www.madbeanpedals.com/forum/index.php?topic=14759.msg141209#msg141209

I have 5V on attack one that doesn't change with strumming & both diodes are oriented properly and are good.

thanx

=======
edit:
just tried 3 different IC1's & IC2's with the same voltages & same result. The CA3080's were purchased after they were confirmed good by another DIYer.

[duck_arse]

erm, Q2. C goes to pin5 IC1, but your listed voltages don't match. the base of Q2 should go lower (I think) as you thrash, as the rect is going negative. starting at ~5V, does it drop with input peak, then rise?

[LucifersTrip]

There's a note in the pdf I linked:

Q2 is drawn incorrectly on the scheme...E & C flipped

[duck_arse]

well, I'm confused. as drawn, it is exactly the same wiring as in, for example, the mutronV. and the note says it works either way, which leads me to - did you try it "the other way?" ("what, and get pregnant?" to complete the only punchline my old man ever told me.) just because it works, doesn't mean it's going to work.

[LucifersTrip]

well, I'm confused. as drawn, it is exactly the same wiring as in, for example, the mutronV.

Yes...it is the same.
http://www.diystompboxes.com/pedals/schems/Mutron%20Micro%20V%202.gif

Funny, I read the first line of the Q2 note in the pdf that says the schematic was drawn incorrectly.
It has since been corrected in the schematic I posted...and I did flip Q2 on the pcb to reflect that.

So, I do have it correct in the pcb, but the voltages I gave should be flipped:

Q2
E: 5
B: 5
C: 0.61

[duck_arse]

yer, it was only after posting that I read closer the build doc thing, to discover that it was supposed to be a microV, even though it appears in the title. ohh, well.

and so, did you do measures on your rectifier workings? and did you get pregnant try it the other way at all? I don't want to look at the board again, it will confuse me more still. and seeing as the drawn C is connected to V+, it will HAVE to be higher than the E, surely? and B and E can't be the same V and work, as you well know.

somewhere, in dynacomp discussions I think, someone (prr?) mentions the 3080 pin 5 do-not-exceed voltage and normal voltages. perhaps a search along those lines?

[duck_arse]

I played with the rectifier section, now I need to decipher my (ah-hem!) notes.

with no 3080 connected, and wired as diagrammed, I had the collector of Q2 at (V/2 + 1V) no sig, dropping by ~1V5 with full sig. the base sits at V/2, and also drops ~1V5 full sig. the emitter was at V/2, and dropped about 1V with signal. and, yes, v. nearly the same either way round.

I dunno how much the vca Iabc would pull the collector down. is it socketed?

[edit: ] this: http://www.diystompboxes.com/smfforum/index.php?topic=35203.msg247401#msg247401 - so it seems the 3080 has a certain pull to it.

[LucifersTrip]

hey d a...

Thanx for taking the time for the replies and sorry for the delayed response. I wanted to figure out what was going on and have the numbers with me.

Bottom line is there was never anything wrong. First, here's the exact voltages when working/not working and all controls set to high noon.

IC1 CA3080
1: 0
2: 5.17
3: 5.17
4: 0
5: 0.61
6: 5.17
7: 9.65
8: 0

IC2 LM1458
1: 5.11
2: 5.17
3: 5.17
4: 0
5: 5.17
6: 5.17
7: 5.17
8: 9.65

Q1
E: 4.49
B: 5.06
C: 9.65

Q2
E: 5.17
B: 5.10
C: 0.61

Q3
E: 5.17
B: 5.73
C: 9.65

I plugged it in again yesterday and it worked again, right away...

When strummed, Attack 1 fluctuates between 2.54 - 5.11V

Since the voltages were the same (except fluctuation in Attack 1) when not working, the problem was probably off board. I needed to duplicate the non working condition (distortion instead of quack and all pots do nothing).

So, I disconnected one pot at a time. Disconnect 1M range: you get a clean tone, pots no effect. Disconnect 100K decay, clean tone 1M range effects tone. Disconnect 2K attack and that was it: distortion, pots no effect.

I pulled the alligator clips on the 2K and hooked em to the DMM and wiggled em around. One had an intermittent connection.

Anyway, everything sounds really good, but I have to make one small change. The range does not sound good (distortion & no quack) until I hit around 140K, so I need to pull the 22K and drop in a 160K...or use a trimmer and set it to the precise spot where it starts to sound good.

thanx again

[duck_arse]

there's no polite way to say "check the bloody wiring", is there? I find that 1M is always too much on these style rectifiers. they just shoot up clipping, and sit there compressing the envelope detail.

nice work, how does it sound? I was about a day away from bb-ing the whole thing (did the ugly face instead).

[LucifersTrip]

there's no polite way to say "check the bloody wiring", is there?

well, you never know when the alligators are going to go. when they do, it's usually not a big deal with a fuzz, since I know em inside and out, but I don't do much with IC's, which is why I asked for voltages...

I find that 1M is always too much on these style rectifiers. they just shoot up clipping, and sit there compressing the envelope detail.
nice work, how does it sound?

sounds really good...very similar to this demo:
https://www.youtube.com/watch?v=viKi_ztL-MY

fat a warbly ccw, and more trebly cw. it's a really nice range. notice in the demo, he doesn't turn full ccw