Hello! My Zendrive has no drive!

Started by SirHugo, April 26, 2018, 10:51:29 PM

Previous topic - Next topic

SirHugo

So I got my PCB from Aion and most all my components from SmallBear. I followed the build exactly with no deviations and it appears to work correctly ( the Led, the bypass, both voice and tone) However I have no drive or volume, they work but there is little to no gain or volume, unless both are dimed, in which case it is super thin and treble-y with crackly break up. I've checked an rechecked all the leads and components and can't find the issue. If anyone has any insights or ideas of the issue, any help would be very appreciated, I've tried to figure it out for a few days and I'm going mad! For good measure I'll add a picture of the cuicit Incase I am missing something visually.
Thanks ahead of time for any help anyone can offer!
JHK






Kipper4

Hi sirHugo.
Welcome aboard.

This will help us to help you if you go here and tell us what we need to do


http://www.diystompboxes.com/smfforum/index.php?topic=29816.0
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

thermionix

Only thing jumping out at me is all the melted insulation at the footswitch.  Check that nothing's shorting out.  Always a good idea to check the circuit function before wiring to the footswitch and boxing up.  Much easier to diagnose and fix if there's a problem.

SirHugo

Kipper thanks man I'm working on getting the rest of the info together.
Thermonix I'll replace the melted wires and see if that helps.
I'll post the metered components here soon.
Thanks for helping me out.
JHK

samhay

Any chance you mixed your drive and voice pots up and swapped them?
I'm a refugee of the great dropbox purge of '17.
Project details (schematics, layouts, etc) are slowly being added here: http://samdump.wordpress.com

SirHugo

Unfortunately no, it seems as though everything is in its place. I'm going to meter the whole thing and reflow again.

SirHugo

Alrighty I mulitimetered the whole thing and here's what I ended up with!
IC1 (AD712)
P1 4.86
P2 4.86
p3 4.68
p4 0
p5 4.84
P6 4.86
P7 4.86
P8 9.72

Q1 (2N7000)
C 4.72
B 4.86
E 4.86

Q2 (2N7000)
C 4.86
B 4.86
E 4.86

D1 (1N4002)
A 0
K 9.72

D2 (BAT41)
A 4.86
K 4.76

D3 (1N34A)
A 4.77
K 4.72

D4 (BAT41)
A 4.86
K 4.77

C1 (470n) 0 - 4.86
C2 (100pf) 4.86 - 4.86
C3 (100n) 4.85 - 4.85
C4 (3n3) 0 - 4.86
C5 (470n) 0 - 4.84
C6 (100uf) 9.72 - 0
C7 (47uf) 4.85 - 0

R1 (470k) 4.85 - 4.68
R2 (1k) 4.86 - 4.86
R3 (1k) 4.86 - 4.86
R4 (10k) 4.84 - 4.86
R5 (1k) 0 - 0
R6 (10k) 4.85 - 9.72
R7 (10k) 4.85 - 0
RPD (1M) 0 - 0
LEDR (4k7) 1.80 - 9.72

Drive (500k A)
1 4.86
2 4.86
3 4.86

Tone (50K B)
1 4.86
2 4.85
3 4.84

Voice (10k B)
1 4.86
2 4.86
3 4.86

Volume
1 0
2 0
3 0

LED (5mm) 1.80 - 0

Power
Tip 9.72
Ground 0




SirHugo

I hope this helps I may wait to reflow Incase anything jumps out any anyone from this information
Thanks again!!
JHK

Kipper4

Your voltages all look ok to me.
So maybe it's a switching problem. Maybe you made a gaff there.
Or something is shorting on the case.
Check the jack wiring.

Do you have an audio probe?
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

SirHugo

Ok well that's good, I'll triple check the switch and in/out put wiring. I do not have a probe but I'm sure I have all I need to fashion one. Hopefully the problem is in the switch/jacks. Though I'm sure I should make one either way.
What could cause shorting on the case? Anything in perticular to keep an eye out for?
Thanks
JHk

thermionix

Quote from: SirHugo on April 28, 2018, 08:55:02 AM
What could cause shorting on the case?

It happens mostly with wired pots, when tightening the nut it can rotate and one lug shorts against the inside of the enclosure.  But you have board-mounted pots, so probably not your problem.

I looked at your pics the other day, and it seems your switch and jacks are all wired IAW the instructions, but I could have missed something.  There's a chance the switch was damaged by heat, going by the melted insulation.  You can possibly figure that out with a meter without disconnecting the wires.

Other possibilities include bad solder joint(s) or solder bridges.  We can't see the underside of your board.  For certain though, it's something simple, and you will get it sorted out.

SirHugo

Ok cool thanks man.
So here's a thing, I get no response on the meter for the jacks on either the sleeve or tip (ofcourse the sleeve would be 0) and the live points on the switch flash .01 then 0. I assume this is not normal?
JHK

Kipper4

That's normal to not get dc voltages on either of the jacks connections.
The input and output caps block the dc. That's partly what they're there for.
If you have a probe you can follow the signal through the circuit and trace where it goes bad .
If it's easy I'd take the board out of the box. It'll be easier to trace.
As someone pointed out it's always a good idea to test the circuit before boxing.
Rock it before you box it.
It helps narrow down the amount of possible issues if you know the board works before boxing.
For future reference
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

SirHugo

I unfortunately do not have a probe. I ha e an update though, o re-wires the switch and it was bypassing normally but then no sound with the effect on, now it seems to be humming no Nate Tre what. I have a distinct feeling that the switch is deadski.

SirHugo

I was wrong lol. I took off all the leads and cleaned them flipped the switch and it's working again, unfortunately the pedal is still not  working properly, it's still thin and trebley and the only way to get any sound is having the vol and gain all the way up. I would to build a probe but I unfortunately can't find a cap for it. I tried the continuity meter on my MM but it dosnt make sound it just flashes a 4digit number then goes away. I'm not sure how to read that.
So as it stands the bypass is working, LED works and effect is engaged but very thin tone and very little output. The switch seems fine. I've triple check my jacks and they are wired properly, all my components are working properly having been metered and catalogued several times. I need to build that probe I guess because I just can't figure this out! Thanks to everyone who has helped me out so far, this has been a frustrating experience but I've already learned a great deal of tips and tricks from you all and I truely appreciate it.
JHK

SirHugo

Well after a week I'm back at square 1. Same symptoms as when I initially posted.

Kipper4

Post up the present voltages of the ic please.
It's more than likely something small, a wiring error etc.

Is it still in the box?

Have you an audio probe yet?
Ma throats as dry as an overcooked kipper.


Smoke me a Kipper. I'll be back for breakfast.

Grey Paper.
http://www.aronnelson.com/DIYFiles/up/

SirHugo

No, no probe yet, I should have a cap for it soon I have all the other bits I need to make it.
Here are my current IC voltages
IC1 (AD712)
P1 4.86
P2 4.86
p3 4.64
P4 0
P5 4.84
P6 4.86
P7 4.86
P8 9.73

I had removed it from the box while I was working on it however I put it back together as I was gonna shelf it and comeback to it with fresh eyes, and I didn't want anything getting dirty or lost. Though while it was out it was very hummy and noisy, which has gone away in the enclosure, I assume the jacks are grounding to it.

SirHugo

Something else I just noticed was that the LED lights weather or not there are cables on the jacks.