Build Your Own Clone Message Board

Hey everyone,

Hello, hope you all are well. I just completed my first pedal kit build, the Royal Flush dual overdrive. And everything works great, with the exception of the hard clipping switches. On both sides of the pedal, when I have the soft clipping switch turned off, and the hard clipping switch turned on, I just get a horrible low frequency distorted drone that won't stop until I turn the switch off. Doesn't matter if I have one side turned on or both. On the first stage side, if I have the soft and hard clipping switches on at the same time this problem goes away, but there is no change in tone, volume, amount of gain, anything. On the second stage side, if I have both switches on I do geth the same horrible noise but it doesn't happen immediately. I have to play a few notes for it to happen.

Curious this is happening on both sides. I have a good Fluke multimeter but am not very well versed in troubleshooting electronics. Tried metering some diodes, but was reading voltage in both directions in diode test mode. I guess because they are still soldered to the board?

For what its worth, I have not done any of the mods, but probably will since I have the guys out of the enclosure.

Worst case scenario, if these hard clipping switches keep misbehaving, can I desolder them from the board and just keep the soft clipping switches?

Thanks!

PCB: https://imgur.com/a/3fwoBxv
Schematic: https://byocelectronics.com/royalflushschematic.pdf
Instructions: https://byocelectronics.com/royalflushinstructions.pdf

I would definitely start by working through this process, since I see a lot of funky looking solder joints: viewtopic.php?f=9&t=52188

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Yeah I was afraid of that haha. I will heed your advice for sure. This is my first time soldering on a pcb. Figured I was bound to screw something up. Thanks for replying.

On a slightly unrelated note, would you or anyone else mind taking a look at the schematic I linked, and tell me more about all these arrows labeled +1/2V? Where is the 1/2V coming from?

If you take a look at the section on the schematic immediately to the left of the label block at the bottom right, that's the Power section. 9V from the power supply comes in, and the voltage divider formed by R21 and R22 (the two 47k resistors) results in half of the supply voltage (which should be around 4.5V) being available at the "+1/2V" at the upper right of that section. It will be used as a reference or bias voltage (sometimes also called a "virtual ground", I think) at various points in the circuit.

I'm sure that the more knowledgeable folks can provide a better explanation

Thanks so much for the detailed response!

Don't bet on it--that looked pretty good to me!

To the OP:

Here are a couple more links to threads that contain additional useful information on soldering quality:

viewtopic.php?f=9&t=6401

viewtopic.php?f=9&t=52211

_________________
“My favorite programming language is SOLDER” - Bob Pease (RIP)

My Website * My Musical Gear * My DIY Pedals: Pg.1 - Pg.2

Thanks for the links. Looks like I'm going to be busy with the soldering iron this weekend. I'm glad I didn't cheap out on my solder sucker.