Hello! My Zendrive has no drive!

[Kipper4]

Look around the stuff on IC1-A
everything from C3 all the diodes and mosfets, gain pot etc- to R4 with the magnifier. Check for cold solder, bad joints.
Also If you check the DC (4v5) on the Vr side of C3 please.

[SirHugo]

Alrighty will do!

[Kipper4]

You are reading the pins right way right?

https://en.m.wikipedia.org/wiki/Dual_in-line_package#/media/File%3APin_numbering_01_Pengo.svg
    ~
1.     8
2.     7
3.     6
4.     5

[SirHugo]

Yes, I am, I double checked just to be sure but yes.
So on C3 I'm reading 4.84 on both ends
As for cold/weak joints I don't seem to see anything that looks perticularly funky
But I'm sure anouther reflow wouldn't hurt.

[SirHugo]

Hmm A few joints look a bit dull so they may be causing issues.

[Kipper4]

Ok great.

Normal voltages you'd expect.
1.2.3.5.6.7 all around Vb. (4v5)
8 @ 9v
4 @0v Gnd

You might experience some meter loading on some pins.

4v8 is in the parish

[Kipper4]

What type of solder  are you using please?

[SirHugo]

Yeah, here's the current IC reads
1 4.85
2 4.85
3 4.66
4 0
5 4.81
6 4.85
7 4.85
8 9.70

I used Rosen core radio shack solder

[Kipper4]

Nice one.

Dull is not good make sure it wets.
Tin the tip. Clean and reflow.
Double check the diode orientations and mosfet.
Not that I see that being much of a problem.

Happy soldering.
Is this your first debug?

[SirHugo]

Yeah it is ! I'm learning a ton from it which is great! I built a BYOC mini rams head, modded a blue box, built this zen and I recently built a steel string clone but this is the first I've had to debug, but this experience though a bit frustrating, has been incredibly illuminating.
I'm gonna go ahead and reflow and report back!
Thanks again for your patience  in helping this novice pedal builder!

[chromesphere]

If that fails Hugo, (although it may seem extreme its simple to do) try testing the pcb externally from the enclosure.  Did you "rock before you boxed" as they say?  This is a very critical step.  It breaks the build up into 2 sections and makes fault diagnosing easier.  If you have tested the pcb, you would know that its 99% likely to be working and you could focus your attention on the offboard wiring.  Im not sure of this pcb's wiring scheme but im sure theres a way to test it externally from the offboard wiring.  I would suggest if you hit a brick wall to try this.  If you find the effect is working you can focus on the offboard wiring.  If you find the effect isnt working, you can focus on the effect (and not waste time with the offboard wiring).  Hope that makes sense!

Paul

[SirHugo]

I may have to consider it. So after reflowing all dull points it seems to me to have a bit more volume than before but now I'm assuming something may be up with the drive cuircit, at this point the bypass works fine, clean signal when bypassed and effect on when on and LED is lit, no extra noise. But the drive sounds weak. IC pins 1 + 6 + 7 still have no signal. Volume pins minus the ground now sound loader but the drive sounds tinny and thin and only really distorts when dimed. Dose any one know how I can post a video in here? I have a sound sample. I'm confused how I have volume and out put if those 3 pins on the IC have no signal, seems impossible on the schematic.

[thermionix]

Dose any one know how I can post a video in here? I have a sound sample.

You can't post it here directly.  You can upload it somewhere else and post a link.  You can upload to youtube and embed here with the youtube button.

[SirHugo]

Ah gotchas thanks!

[SirHugo]

Dose anyone have any idea how pins 1 6 7 on my IC could be dead on the probe but functioning via meter and still some how sending signal to the volume? This seems to be the problem that's been plaguing me.

[Kipper4]

Heres how it works.
The DC (that you're reading with the meter) Powers the componants.
The Ac that your trying to listen to with the probe (guitar signal) May have been disconected at some point. And Is not getting through from pin3 to 1
or from pin5 to 7

usually its a wrong part or bad joint somewhere.

[SirHugo]

Oh ok I gotcha! Well I know my components are correct, so there must be a connection issue somewhere though I can't seem to find it.

https://youtu.be/0CRcLRJnHzA
Here's a sound sample of it bypassed then on, please note both drive and volume are all the way up. I don't know if this will help but perhaps it will give some clues.

[Kipper4]

Certainly sounds like it's working.
I'm hearing distortion right?
Only thing is it should be way louder when dimmed.

[Kipper4]

Look around the R3 ,voice pot ,C3 network.

Also double check the gain pot wiring.

[SirHugo]

Yes that's been my struggle, everything is working it just has some gain/bass loss somewhere. I'm probing about and here's what I've found
R3 1 rounded distorted signal 2 bright distorted signal
Voice
1 distorted signal
2 distorted signal
3 distorted signal (slightly louder than the others)
C3 1 rounded clean signal 2 distorted signal
Gain
1 no sound
2 distorted signal
3 distorted signal
C2 1 no sound 2 distorted signal
R2 distorted signal on both sides
R4 1 clean signal 2 no sound
And it's not in the area but I descovered the + end of C6 has no signal