Sunking 1 build bugs/problems

[SloClone]

Hi,

I've had this pcb for a while now, and decided to complete the build.
I soldered all the components to it and wired it as well as I could (true bypass), using the old manual (http://www.madbeanpedals.com/projects/Sunking/docs/Sunking_ver.3.pdf) and omitted the C3, r3,4,28,29,30 and added the 1M rtb. It turned out to be more complicated, because I have a ver. 3 board and the wiring in the manual uses the ver. 2. But I think I've managed it.

I tried to test it for the first time, plugged in the AC jack and got a clean signal. When I engaged the pedal, I got a monotone sound and (almost) no signal. When turning the pots, I can hear in the signal they have effect on the signal.

The IC's all get voltage, but I don't seem to be able to find the problem.

Could anyone help?

Thanks
Sander

[luks999]

The build doc says 2 different things here:
1) omit c3, r3, r4, R28, R29, r30
2) at the wiring diagram (true bypass): omit c2, r3, r4, R26, R27

[luks999]

btw im pretty sure C3 is a typo and C2 must be omitted, otherwise there would be no connect to the input of the circuit!

so i guess the correct procedure for true bypass will be:
-) connect R28
-) omit R27
-) omit C2, R3, R4
-) omit R29, R30 (?)
-) connect everything as in the true bypass wiring diagram

please correct me if im wrong here!

[madbean]

The fabricated and single sided PCB components are labeled a little differently. He's got the parts correct to omit if he's building the fabricated board.

Sander, a pic of how you have it wired would be helpful here.

[SloClone]

pics, let me know if you need more.
sorry for the sloppy wiring, but I always try to make it work first before making it tight and clean.

[luks999]

seems to me as you wired your 3PDt switch wrong.

you connected the input to ground, that means that the effect input is grounded when you kick the effect on.
remove the ground wire from the S2 and see if it works

@Brian: sorry i didnt look at the fabricated one. but i got it now

[luks999]

btw: if pcb not grounded, solder s2 to ground

[SloClone]

Yes thats what I did, right?

[luks999]

the pcb input must be grounded when the effect is off, not when its on
in your wiring it gets grounded when its on, and therefore you have no signal (at least thats what i think, that happens)

in my opinion the 3PDT lug below the center position (where the red wire is soldered) needs to be grounded instead of wheres s2 currently soldered

do you know what i mean?

[luks999]

add: measure the input with a multimeter when you click the effect on. when you have a direct connection to ground then, thats the bug

[luks999]

im curious, hows your build going? did you fix the issue, sander?

[SloClone]

Sorry, I didn't had time to get back to you guys earlier. I fixed the problem of having almost no signal, so thanks for all the help. turned out to be a grounding problem on the board, but S2 is still in its place... I found it difficult to use the v3 board and the v2 wiring diagrams, but it worked!

Now I'm only left with the monotone sound (not really a hum) in the board. I changed out all the ICs and that didn't fix it. The quest continues!