No Power/LED when Connecting Power to Pedal

[snot_kid]

Hi team.

I'm not entirely sure what I'm doing wrong, but I've built the Blue Shoe Gai Pan into the enclosure, and the LED/pedal isn't powering up when the footswitch is engaged.

The DC jack is isolated, and the pedal is powering up when the 1/4" jack in/out aren't wired up to the enclosure, so I'm assuming it's a grounding problem? I am using metal 1/4" jacks.

There's no continuity between +ve and -ve power, so there doesn't appear to be a short, but it's acting in that way?

Very confused. I've built many other DIY pedal kits, and this is the first Im having problems with.

I'm assuming metal 1/4" jacks are fine, as loads of my other pedals use them with isolated DC jacks...

Please give me some help!

Thanks - Keria

 

[snot_kid]

I know it doesn’t help with this issue but if you can adjust the temp of your soldering iron I would turn the heat down a bit. The board looks like it has been really hot in multiple places. If your not careful you could damage a part or even a trace. Black boards are the worst for showing solder splatter, heat etc but this one looks a little rough. I am pretty new to this forum but have built tons of pedals over the years so I apologize if this comes off as rude. You may want to get some vero boards and adjust the heat and practice. Not only will it make your builds better but it would also make it a little easier to see the joints to help trouble shoot. I speak from personal experience. I have cooked a few boards in my early days, lol.

I appreciate the feedback. I'm using my JBC station and the temp is set to 350 celcius. The pics do look rough, mostly cause I haven't given the board a proper clean. Most of the marks/shiny areas is just residual flux. The pedal does work FYI, just not within the enclousure, so I'm not too concerned with the solder joints. I made sure to check the solder joints after installing each component and reflowed each just to be safe. I use a soldering iron pretty much every day for work, but was just a bit lazy in this case. My IPA came in yesterday and the board looks a lot nicer. I should probably update the pics, as it's night and day.

 

[snot_kid]

With power on, and the black lead of your multimeter on the - wire from the jack, and the red lead on the + wire from the jack what is the reading?

I'll get onto this later today. I'm needing to resolder the wiring on the jacks and footswitch, so I'll get that done and run some tests.

 

[snot_kid]

Ok I'm getting somewhere...

After rewiring elements and swapping the jacks + footswitch, I can get the pedal to turn on with the jacks installed.

I've now realised that it's the pots that are giving me trouble. As soon as I begin to turn the nut to tighten 3x of the pots (Mid, Drive, Push), the pedal powers down and the LED turns off. It also disables the power running to other pedals down the chain (my Cioks must be disengaging the power as a safety). Is this just bad pots, or is something else at play? All of them minus the dual gang have the plastic isolation, and I've taped over a few as a precaution... I'll try swapping them out for others.

 

[snot_kid]

Installed new pots, exact same problem. I think I'm gonna put this build on the back-burner and try my luck with another one

 

[PJS]

The behaviour of the power supply suggests a short somewhere in the pedal - the short is drawing to much current and the supply is shutting down as a protection. Did you ever go back and measure the power jack again? Your earlier post had the +ve lead 9V lower than the -ve lead, which is backwards. If you have managed to get the power leads reversed that could also potentially explain the behaviour you described with the tightening of the pots.

 

[snot_kid]

The behaviour of the power supply suggests a short somewhere in the pedal - the short is drawing to much current and the supply is shutting down as a protection. Did you ever go back and measure the power jack again? Your earlier post had the +ve lead 9V lower than the -ve lead, which is backwards. If you have managed to get the power leads reversed that could also potentially explain the behaviour you described with the tightening of the pots.

Oh yes, sorry I forgot to post this earlier. I tested the leads, and the +ve terminal was reading just over +9v, reference to ground (-ve terminal).

 

[ClippyTheDiode]

It may be that dual gang pot touching the center leg of the pot above it. Can you get some sort of insulation between them?

 

[Laundryroom David]

It may be that dual gang pot touching the center leg of the pot above it. Can you get some sort of insulation between them?

Friggin dual gangs

 

[Audandash]

Is that are wire strand I highlighted next to the power wire? What is it you are using under the pot to separate it from the board?

 

[Nic]

Definitely looks like stray wires... You've got some eyes!
Looks like tape under, I like to order some spare pot covers and cut an opening in them to fit on duals.

 

[snot_kid]

Coming back to this thread as I've just finished finalising my new pedal board.

So after completing 3x other PedalPCB builds, they all work 100% on the first go (Parentheses [Big + Mini build] and Mofeta Preamp), and I've come to believe that there might be something wrong with my Blue Shoe Gai Pan PCB.

Aside from tracing all the components, or rebuilding the PCB with new components, I think I'll just buy another PCB when I do my next bulk purchase and give it another go.

Thanks for the help everyone!

 

[Laundryroom David]

Coming back to this thread as I've just finished finalising my new pedal board.

So after completing 3x other PedalPCB builds, they all work 100% on the first go (Parentheses [Big + Mini build] and Mofeta Preamp), and I've come to believe that there might be something wrong with my Blue Shoe Gai Pan PCB.

Aside from tracing all the components, or rebuilding the PCB with new components, I think I'll just buy another PCB when I do my next bulk purchase and give it another go.

Thanks for the help everyone!

Fair enough. I’ve built a lot of pedals and have yet to experience a faulty pcb. They do happen, but exceedingly rarely.

I finished a pedal yesterday (Aionfx legacy Comet) and was almost ready to say the board was to blame. Then I re-read the schematic and realized I had misunderstood the build (you can build it several ways with different values of resistors and caps etc). I realized the reason I was getting no tunes was the voltage being way off at a pin of the IC that connects to vref. Traced it back to a MISSING RESISTOR from vref to this to that to … the pin of the IC with the wonky voltage. I put the resistor in just to test and lo the beauty of the DS-1 roared to life. To be clear, I missed a resistor, Aion’s stuff was not missing a resistor.

I had reflowed all joints, done a close visual inspection of the board, checked voltages and continuity (obviously not well!) and was still not getting sound past Q2. Must be the pcb, oh wait what does the schematic say about … oh shit.

So it is entirely possible that the board is to blame, but maybe … see above lol. Taking a break from a build never hurts, either. If you build up a new one, let us know how it goes!

 

[snot_kid]

Yea that's a great point. The build has been set aside for now, so maybe I'll pick it back up in the next few months or so.

 

[Robert]

Just noticed this.

It's most likely the dual gang pot (it's always the dual gang pot).

Insulate it with something better than tape, like one of the potentiometer insulators.

 

[snot_kid]

I haven't had any issues with other dual gang pots and the tape I use, but maybe I should buy a few of the insulators and see.

 

[Laundryroom David]

Just noticed this.

It's most likely the dual gang pot (it's always the dual gang pot).

Insulate it with something better than tape, like one of the potentiometer insulators.

Friggin dual gangs

May I just say again ☝

 

[Laundryroom David]

I haven't had any issues with other dual gang pots and the tape I use, but maybe I should buy a few of the insulators and see.

I really like ‘em. Simple way to cut down on friggin shenanigans from friggin dual gangs

 

[giovanni]

+1, tape never works for insulation. I had a short between a pot and an LED bezel that I tried to fix with tape. No dice. Plastic bezel fixed it.

Edit: Recently I just used a piece of cardboard to insulate a dual gang pot.

 

[swelchy]

I was gonna say it's the tape..... sharp little boogers will always poke through tape and ground out the pot... especially after cranking the pot knobs down..

 

[snot_kid]

+1, tape never works for insulation. I had a short between a pot and an LED bezel that I tried to fix with tape. No dice. Plastic bezel fixed it.

Edit: Recently I just used a piece of cardboard to insulate a dual gang pot.

I was gonna say it's the tape..... sharp little boogers will always poke through tape and ground out the pot... especially after cranking the pot knobs down..

Thanks for the input! It would be the first time for me that tape has been the culprit, as I've had good results previous times. I'll give the isolators a try next time