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Almost certainly not. It will be a cylinder with a metal label wrapped around it. You probably won't be able to identify the correct one without removing the board and looking at the traces. One leg of the capacitor that you are looking for will be directly connected to one end of the...

Yes, I think I would be pulling out the cap in parallel with the resistor that you have marked as 8.9 and measuring the voltages again. I am 90% sure that will ring that 0.26V back up to 4.5v or so

I think those are the 2 resistors you are looking for alright, and that 0.26V corresponds to the bias voltage you are getting at the op amps. That 0.26V should be (with 9.29V as the input voltage) about 4.6V. It looks as if something is shorting that voltage nearly to ground. The resistor...

In the seabed delay linked to above, the resistors in question are 10K (brown, black, orange) which is fairly standard. I can see you have a few on the board in the right place, so use a continuity measure on your multimeter to find the right ones. One will have one end on 9V and the other...

You can do it from the top as long as you can work out which resistors are giving you the 4.5V. Essentially there would normally be 2 resistors between the ground and 9V, and the point where they both join would be halfway voltage, so 4.5V for a 9V power supply. That 4.5V is used to bias the...

That looks like a problem. I would be expecting 9V on 8, 0 on 4, and about 4.5 or so on the rest. You will need to get those voltages sorted before moving on. Somewhere near where the power comes into the board I would normally expect a network of components to derive that 4.5V and some...

The switch lug that you have marked yes is the lead running into the PCB, so that tells us the switch sees to be working. For the rest you will need to be able to see the traces on the board, so you might need to carefully take it out of the case. Before you do that though I want to clarify...

It sounds as if the main problem is the clean signal from after it goes to the delay chip but before it goes to the mix pot. You probably need to make an audio probe and probe the clean signal and see where it dies. You may need to trace out some of the traces to work that out.

OK. It is not certain, but I would be looking for the problem between R16 and the output. It might be earlier in the circuit but I would think the end part is more likely. First steps are checking the voltages on the op amps, checking component values, checking for bad solder/shorts. If that...

If all else fails I'll try lowering R12, but so far it doesn't look like it will be an issue in a real world use.

Seems like it is time related. For the first few switches after power is applied, or during the first few seconds/maybe minutes after power on there will be a pop - after that it is silent. I am starting to think that it might have something to do with the power supply I use to test maybe...

Thanks. I will investigate more

Hi, I have built 2 Drebbels and they both thump when engaged. Is this just the nature or this schematic or is there a way to reduce the thump?

Can you be a bit more specific? I am assuming that the low volume is when the pedal in engaged? Is that correct? Also, the gain knob. Does it work as intended or more like a volume knob?

A lot will depend on the capacitance in the circuit. There are 10uF capacitors across the power supply which is a good start as they are well under the 100uF which is specified. Traco also do this kind of converter, but I am not sure if the pinouts and sizing are the same.

I think from memory I have 3 diodes soldered together to replace 2 diodes in a king of tone clone to get the same overall Vf as in the original.

Yep. I know from experience that if I try to troubleshoot when I am frustrated I can do more harm than good. It can be an idea to leave it for a bit and come back calmer. When you checked all you components did you check the markings, or did you measure them (Measure resistance and...

I just finished one of these. When it was first built it did the same thing - with the rate light on continuously. Then I remembered to put all the ICs into the sockets and it worked perfectly. I have even changed R11 to a higher value because I am using high brightness LEDs and it works...

It looks to me as if 2sk208 and 2sk30 have different pinouts, so you will have to take that into account if you are substituting

The gain pot increases gain, but it also blends between clean and dirty signals. If you are getting no overdrive and the gain pot acts as a volume it is almost certain that the signal is just not getting through the overdrive part of the circuit at all. If it was me I would be tracing through...