[Billy]

It’s difficult to see but I’m assuming you have both G2 and the pcb ground going to the DC jack it looks like there is a ground wire going under the pcb to the main ground pads

All your component values and orientation that I can see look correct

Regarding the jumpers for the BBD obviously make sure you’ve got them oriented correctly for the V3207

To check you’re actually getting power into the pcb check voltage on the mini me main 9v and ground pads where you should read around +9v

 

[Billy]

I don’t see any jumpers under the BBD it’s easy enough to forget those but you definitely need them

I’ve built over 10 of these so it’s not the pcb

I’d probably ground G2 to the DC jack they’re 2 separate ground planes

[Billy]

All your component values and orientation that I can see look correct

Obviously I can’t tell the orientation of your LEDs  if you look down on them the cathode negative side should be flat and go to the striped side

The internal cathode pin should be much thicker than the anode

Afaik this pedal should have a good bit of gain you could use 12v or more depending on the voltage rating of your capacitors etc

Are the back of the pots insulated it’s difficult to see if they have the plastic caps on them

 

 

[Billy]

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Lack of gain or drive could be caused by several things

Post some nice clear well lit images of your build so we can clearly see all component values and orientation and trace your offboard wiring

The LEDs are being used to clip the signal not all clipping LEDs will light up D1 and 2 as you can see are soft clipping diodes in the op amp feedback loop which won’t normally light up whereas D7 and 8 are hard clipping LEDs connected to virtual ground which will usually light up

Your op amp voltages look good aside from the pin numbers 5 to 8 are backwards

IC pin numbers are pin 1 left of the dot or notch down to 4 then up and around the other side in a U shape 5 to 8

[Billy]

The original used BC209C, BC183 or BC184 transistors

The more modern 2N5088 will do the job

[Billy]

Nice Brent

I’m partial to mojo components myself the Japanese germaniums are definitely my favourites they’re always consistant and seem to work great all the time

I’m sure he’ll love it

 

[Billy]

Did you try adjusting the trimmer in small increments if you have

You want to check the LFO section below, I’m not familiar with the circuit it looks similar to the univibe, looking at the schematic I’d first check you get a pulsing voltage on Q5 collector

Post some nice clear in focus images of you pcb so that all component values and orientation can be seen

 

[Billy]

What voltages are you getting on the transistor pins you shouldn’t get continuity directly from 9v to Q1 collector R3 should connect to 9v with the other side to Q1 collector and Q1 emitter should connect to ground check you don’t have continuity on Q1 pins

Make sure you don’t power the circuit when checking continuity and taking resistance readings

[Billy]

I’m so sorry to hear this terrible news

Ray was a very knowledgeable guy and always willing to share his technical abilities with patience and grace

I  used to enjoy the personal banter we shared both having served in the forces Ray as a US Navy pilot and me as a Royal Navy electronic warfare operator his job to get me and mine to make sure he didn’t

We had a lot of laughs with plenty of wind ups I’ll miss the big man

 

 

 

 

[Billy]

You can solder one of the transistor pins in the socket to hold it in more securely

[Billy]

Your guitar signals AC so you don’t want DC on the out pad

Are you actually getting audio through the circuit in effects / bypass mode

Do your 2 pots on the underside of the pcb also have the plastic caps on them

You should obviously get bias voltage on both transistor collectors etc If you get no voltage on Q2 collector try reflowing solder joints on R4

You can check resistance along that trace, don’t power the circuit and check resistance from a 9v pad to Q2 collector where you’d expect around the value of R4 22K

Also check resistance between Q1 collector and Q2 base where there should be little to no resistance

If you get high resistance readings or OL (over limit) theres obviously a problem along those traces poor solder joints or solder bridges or damaged traces all your resistor values look correct so I wouldn’t suspect an incorrect value to be the problem

Q2 base voltage should be exactly the same as Q1 collector

The circuit is basically a modded fuzz face with extra pots and EQ

So I’d think you’d want similar to fuzz face voltages 1.4v on Q1 collector, base 0.6v emitter 0v,  Q2 base 1.4v, collector 4.5v emitter 0.8v mastodon voltages would be affected by the pinch and wool pots so may not be exactly the same

 

 

[Billy]

Are you getting power to the pcb check on the main pcb 9v and ground pads some boards require D1 installed they’re either series 1N5817 (required) or parallel 1N4001 (not required) the quickest way to check is to see if you get voltage to R3

Your pcb is V4 so D1 is a 1N5817 and needs to be soldered in hence why I asked if you get power into the pcb if you don’t have the diode you can solder a jumper in its place

The polarity protection diodes were changed to 1N5817 because of its lower forward voltage allowing less voltage drop into the circuit

[Billy]

Yes you’re correct there’s different board versions the pads with the white squares will also have a small T for tip

So you want those pads to go to BI and BO and the actual jack tips to go to I and O

Then you can either ground your jacks to the main board or the 3PDT board

The pcbs are updated from time to time for improvements like board mounted pots etc

 

[Billy]

I can’t see your IN jack wiring clearly but I think its correct

Your OUT jack tip should go to O on the 3PDT pcb and your BO should go to the main pcb out with the white square around it

Yours has your out jack tip going to out on the main pcb and your BO going to out ground on the main pcb

[Billy]

Swap your black and white wires on your jacks around

 

[Billy]

As you know the enclosure itself will be grounded make sure none of the pot lugs are touching the enclosure causing a partial short to ground or you could try insulating where the treble pot goes through the enclosure with a thin piece of plastic or tape

I had a similar problem where when I tightened the pots up they moved and pot lugs touched each other

Yours look straight but you can’t always see if they move and touch something they shouldn’t

I can’t quite make out if all of your pots have the plastic covers on the rear if they don’t insulate the back of them so they can’t short on the solder side of the pcb

[Billy]

Try the gain pot mod I detailed above if you check the link you’ll see I did a bit of work to get a nice range  across the gain pot

It should have plenty of gain and volume make sure your volume pot has nice solder joints I’d suggest using an audio probe to see if you can find where the volume level changes or drops

[Author]

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