Skeptical Buffer Build Instructions Discrepencies - Problems Resolved!

[BQFS]

Hi -

I am a brand new pedal builder. I received a whole bunch of PedalPCB boards from a guy who gave up and now I am working my way through them, ordering parts I don't stock.

I am a retired electronics technician, and am not new to troubleshooting or building out circuit boards, but this one has me puzzled.

If I am not posting this correctly, I hope someone will move this to where it may better belong.

The first thing I did was to print out the build instructions. The only one (so far, and I have looked through about a dozen build instructions) that I am having difficulty with is the Skeptical Buffer. First, R13 is 10R, not 100K like a previous poster figured out.

But the layout of my board isn't the same as either of the two shown in the build instructions.

Starting from the top of the board and working downwards, on the "row" with the three switches,on my board there is room for two rectangular caps in between the switches. On the instructions, it shows four caps, two box caps on the outside of the left and right switch, and two circular caps between the switches.

On the left side of the board, there are three circular caps, C6, C3, and C105. On my board, only two caps, 10uf and 1uf.

Under the printing of Rev 2, there's a row of four caps. On my board, only three caps.

Under that "row" on my board there is one circular cap to the left of the two diodes and one to the right of the two diodes on the right. On the first page pictorial, there are two box caps to the right of the right-most diodes and no cap to the left. On the page 2 pictorial, there are no caps on either side of the two sets of diodes.

That appears to be it. I would certainly appreciate a pictorial that is correct for the board I have. Failing that, if someone could just tell me which caps go where, I would be very appreciative.

Thanks in advance for anyone's assistance. I will be glad to post a pic of the board if that will help.

Bud

 

[Robert]

You have the previous version of the PCB, follow the printing on your physical PCB for component placement.

The wiring diagram is the same as the current doc.

Ensure that the drill template lines up, there was an initial release of the PCB where the toggle switches were closer together than the current version.

 

[Nostradoomus]

The board has gone thru a few revisions. Just go by the values printed on the board and you should be fine.

 

[BQFS]

Thank you for your reassurance.

 

[BQFS]

I did get the board done, after making sure to put the switches on the wrong side first. I desoldered them and moved them to the correct side.

Then I grabbed the wrong template and drilled the holes too close together, so I widened them and covered the excess with huge washers. Looks really spectacular (pardon my sarcasm).

For the finishing touch, it turned out the 3PDT board was defective. The trace was open between the SW hole and the top middle switch lug. Wow. I don't think I will be buying any more of those. I ended up soldering the SW wire directly to the top middle lug, and the board now works fine.

I play bass, and now wish I had wired the switches out of circuit. If there's a difference, I sure don't hear it. Oh well.

 

[Feral Feline]

I did get the board done, after making sure to put the switches on the wrong side first. I desoldered them and moved them to the correct side.

Then I grabbed the wrong template and drilled the holes too close together, so I widened them and covered the excess with huge washers. Looks really spectacular (pardon my sarcasm).

For the finishing touch, it turned out the 3PDT board was defective. The trace was open between the SW hole and the top middle switch lug. Wow. I don't think I will be buying any more of those. I ended up soldering the SW wire directly to the top middle lug, and the board now works fine.

I play bass, and now wish I had wired the switches out of circuit. If there's a difference, I sure don't hear it. Oh well.

BOLD emphasis mine. ➚

As I mentioned in your other thread, it's not impossible to have a defective board, but after seeing your post here (bolded text above) I've gotta say I doubt the 3PDT-board is defective — because...

The "SW" on the daughterboard connects/is-hardwired to the centre-lug (lug #5);
the switch itself makes the final connection to lug-4, lighting up the LED when you turn the effect on and close the circuit.







You can use your DDM's continuity-setting to test this on your boards.

PedalPCB's boards are based on a coherent system — most, but not all, projects are within specific guidelines to make building easier, from one circuit to the next. Very consistent. One drill-template can work for dozens upon dozens of different builds, for example (mentioned because you had trouble with the template for this build, revised version vs old board).


I'll be looking for your road-test report in your other thread.