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IC2 Pin 4 should be -9Vish. IC100 pin 5 should be negative read to ground (-9V). Defective charge pump?

That chip is great for anything you want uncolored / low distortion.

Cool. I'd still recommend testing the ohms readings between pin 2 and 1, then 3 and 1. The reason I say that is, with the volume pot being the very last component before the output jack, it should mute any noise or signal when turned completely off. Sounds like you got solid advice on the...

Did you try and put a signal (guitar) through the effect? If yes and you heard guitar sound, does the volume affect the loudness of the guitar? My logic: This circuit emulates a combination of a Rangemaster treble boost into a Laney Supergroup amp, to which the real deal is hissy and fizzy. I...

@Feral Feline - I agree for that application.

I repurposed the stock SPDT of a Vox wah which has a very long thread neck to reach the treadle that no 3PDT that I could source could be found. The stock SPDT becomes in essence a SPST for grounding the relay coil and the LED indicator at teh same time. The common lug is sent to ground and the...

Exactly!

Yes, except my design can use the existing SPDT stomp switch, alleviating trying to find a 3PDT (my design can simultaneously actuate an LED indicator) with the right height throat to actuate the effect or true bypass. Plus, 3DPT typically require more downforce to actuate and are mechanically...

Reading back on your original post, I wasn't clear on exactly what it is or is not doing. Is it lights and no sound when the effect is engaged? 18v into that charge pump circuit would have created a burst of 32+ volts (it may have surged even higher). A TL072 is rated at 40V but can be...

It could be that the charge pump is defective, perhaps with an internal short. +9VDC supply should render around +8.5VDC after the 1N5817 & 100ohm resistor. The voltages indicate no voltage doubling and more current than designed, going across the diode and resistor, causing additional voltage...

Putting +18VDC would at first, fry the TC1044S. Next, C101, C102, C103, C24, D101, D102 and all transistor / FET components would have to be checked. The charge pump may have generated 31VDC for a few hundred milliseconds, which could wipe out 25V caps, The transistors and FETS might have...

The more gain stages, the more the self-noise of the ICs gets amplified. Many designs combat that with 47pF to 470pF negative feedback capacitors in the gain circuit.

That is a clean build!

Good recommendations, thanks! I'll have to experiment with them. This was built to the client's desires, who has a love / hate relationship with Tubescreamers. His main complaints were 'fizzy,' 'nasal mids,' 'too much gain, not enough grunt.' His main guitars for this pedal, are all...

I have not heard or built this drive, nor the one it is similar to. Looking at the schematic, that should have decent volume. I'd suggest posting pics of the populated board and double checking the component values, while waiting for other member's responses.

"The bad three pots dont have continuity..." If pins 1 to 2, 2 to 3 and 1 to 3 all do not have continuity (defined in the case of installed pots as: pot values in context to the resistance of the circuit), then your pots are bad. Not uncommon to have a factory pot problem where the metal lead...

I met a guy who claims he was audio probed and the aliens were rough on him. Kidding aside, I use a mobile phone, a four conductor 1/8" jack which converts to RCA with 1/4" phone plug, an app called 'Hz Frequency Generator' and create a 1Khz sine wave with the volume on the phone about 3/4's...

Where did you buy your charge pump (IC7) from? Normally, to determine if it is a bad charge pump whine you would remove IC7 and work off of 9V. However, this design derives its Rref and IC power return from pin 5 of the IC, so if you remove the charge pump it won't work at all. Charge pump...

Thank you. Your FET voltages indicate shorted or near shorted FETs, perhaps from overheating when soldering or you received a bad batch. They should be something around: D = 8 VDC G= 4 VDC (mid-way between D & S, for symmetrical clipping) S = 0,6 VDC (all voltages depend on the bias trim...

Are your FET voltage measurements in relation to ground? As in, common probe to ground (black) and hot probe (red0 taking the measurements?