@billy
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Post some nice well lit images of the pcb so that we can clearly see all component values and orientation and trace your offboard wiring to DC jack in and out jacks and 3PDT switch
With your experience I can’t see you having many problems Bud aside from those things that are peculiar to guitar effects circuits but I’m sure you’ll suss them pretty quickly
I look forward to you being on this forum and hopefully learning a thing or 10 from you
The boards are designed for common anode bi colour or standard LEDs
The older build docs will have the information in the status led section newer ones it’s usually an image of the 3PDT pcb showing which pads to use for both a bi colour and standard LED
It’s definitely possible Bud I know because I’ve done it many moons ago
From what you’re saying it sounds like your circuit is working and it’s just illuminating the LED in the wrong switch position
And just to emphasise how easy it is to mess it up you may have noticed I’ve edited my post if it’s a standard LED cathode pin should go to the pad without the white square, anode to the centre pad
Could it be that the LED is simply wired incorrectly and comes on in bypass mode rather than effects mode if you’re using a standard LED the cathode should go to the solder pad without the white square and anode to the centre solder pad
Post an image of your pcb so that we can see all component values and orientation and trace your offboard wiring
The 100uf is just a power supply filter cap so won’t affect the audio circuit anything from 22u up to 220u is fine there for everything else I’d go with the ritual fuzz values
What’s the piece of wire near R6 coming from the under the BBD make sure you snip off any excess like that if it is part of the jumper it’s hard to tell if it’s actually touching R6 solder joint
Post an image of both sides of the pcb as it is now
I’m thinking even with a 6v bias voltage on the 4558 you should still get a mis biased sound through the pedal
Your grounding issue seems to be the cause of your incorrect voltages with the most likely candidate being the BBD jumpers
Obviously you should get 0v on Q1 emitter, pin 4 of the 4558 and pin 1 of the BBD ( I think) you’ve got 3v try reflowing the BBD jumpers
The LM358 ground is separate and that’s OK
Your voltage divider R32 and 33 appears to be working and both look to be the correct value 56K
Take voltages on the 4558 socket with the IC removed I’d expect pin 4 to still be 3v indicating a problem on that ground plane
Does the voltage oscillate on the LM358 pins 1,5 and 7
Your 4558 voltages look high pin 4 should be 0v ground the others around 4.5v except pin 8 which should be power around 9v
What voltage do you get at the junction of R32 and 33 where they are connected on one side of R32 you should get around 9v on the other side around 4.5v and one side of R33 should be around 4.5v the other 0v
Which transistor is Q1,2 and 3 on your voltage diagram is this correct
As mybud says voltages will give us an idea of what’s going on
ICs etc heating up can mean you have a dead short somewhere ie power connected directly to ground drawing excessive current
Without powering the circuit check that none of the LM358 pins have continuity with the IC both in and out of socket
Did you fix your in and out jack wiring from your initial reditt post
Depending on how long you had it powered with your previous faults you may have damaged the LM358
I’m sure you’ll figure it out Mason it’s basically a process of elimination
You know you’ve got 9v from your power supply into the DC jack if after you reflow solder joints its still faulty
I’d disconnect the jack completely, desolder your wires from it, plug power in and check what you get on the solder lugs that’ll at least confirm the jacks good or not then we’d know something in the circuit is dropping voltage
Where is the kit from
Sounds like the DC jacks the problem if it gets 9v in and only 6 out
Make sure you’re placing your meter probes on the actual solder lugs not the wires or solder joints on the jack
If you haven’t already reflow the jack solder joints and push your ground wire through more and snip off any excess bare wire
Continuity check there’s no connection between each solder lug and solder lugs to enclosure you should get infinite resistance
Where did you get the DC jack
I’m glad it worked Tiam
Now you know it’ll work for any suppliers pcb simply connect in, out power and ground and off you go
What are you using to power it is your power supply putting out enough voltage
If it’s an adaptor check the label and measure the voltage it’s putting out simply put your meter ground / black probe into the centre of the adaptors socket and put your red probe on the sleeve you should get a positive voltage if it’s a centre negative adaptor
You’ll need to find out where you drop voltage
If the adaptor puts out sufficient voltage plug it in and check voltage on the DC jack solder lugs
Yes it should be fine just connect your gpcb board snd, rtn, power and ground wires to it, power it and plug your guitar and amp to the jacks as you normally would
I’m not familiar with the auditorium but I’d assume it’s exactly the same as a test box so gpcb +9v and ground wires connect to + and – at the top of the auditorium and snd and rtn wires to the bottom screw terminal in and out you don’t need to bother with the auditorium LED ground and SW or the gpcb in and out which are the jack tips I think and the auditorium has the jacks onboard
Looking at the schematic SND is the circuit input and RTN output
