Odd Issue with a Vero board Magnavibe Build

[cabinmusic]

Hey all, hoping to get some insight from the experts here. I am building a Magnavibe based on this vero board layout. The pedal passes signal when engaged but it is dry, with an addition of some noise, which oddly enough IS being effected by the LDR/LED combo. So I've got a clean signal running through unaffected and noise being effected. I am currently using this LDR with a red LED. No other modifications or changes to the layout. Really scratching my head on this one!


Voltage at the circuit board end of the red battery lead = 9.2
Voltage at the circuit board end of the black battery lead = 0

Now, using the original schematic as a reference for which part is which (that is, which transistor is Q1, Q2, etc. and which IC is IC1, IC2, C1, and so on) measure and list the voltage on each pin of every transistor and IC. Just keep the black lead on ground, and touch the pointed end of the red probe to each one in turn. Report the voltages as follows:

Q1 (MPSA18 on left side)
C = 0.35
B = 0.05
E = 0.04

Q2 (MPSA18 on right side)
C= 0.30
B= 0
E= 0

D1
A (anode, the non-band end) = 0.37
K (cathode, the banded end) = 0.30

I've also tried in a pitch black room so I don't think the issue is light leakage. Any help or tips greatly appreciated!

[duck_arse]

three things, cabinmusic:

- post the schematic you are looking at. there are hundreds for the magna, which is yours?
- post photos of the thing in front of you. we can always see things.
- welcome to the forum.

[cabinmusic]

Hey duck_arse, I linked the vero page which in turn has a comment saying this is the schematic.

Here are photos, it's a bit of a mess an unfortunately I only had white wire. The duck tape is wrapped around the LED/LDR combo to block out light.

Thank you! Let me know if I can provide anything else.

[duck_arse]

ahh, I see, well. you have me at a disadvantage in that I'm having all sorts of interesting problems w/ imgur at the moment. if you post those images in the page I can see them, but if you post their links to the image instead, I need to jump thru hoops just to get a glimpse.

a quick glance at your voltage measures suggests you have no supply volts. you need to track down where your 9V apeears and where it doesn't. the first transistor should be abot 6V at collector and 3V at emitter, thereabouts.

[PRR]

problems w/ imgur

postimg.cc  ?

[duck_arse]

thanks Paul. kind of.

well, I see you have built the famous mirror image version. when you look at the layout cuts map, it is from the component side [in this case], so the cuts/underside/copperside needs to be mirrored. if you mirror the parts layout, well, all bets are off, it's too difficult for us to think about.

I'd suggest start again. and when you make those vero cuts, be sure to make them clean, no little slivers or half-moons of copper left behing. scalpel, your friend. and when you clip the leads, clip them down close to the solder, there's nothing good comes from leaving those stumps.

[cabinmusic]

Ah shit I didn't even notice it was flipped! Chock it up to being a vero beginner I guess, I'll try rebuilding from scratch and see where I get. Thanks for the help y'all.