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I was wondering if any of the fine PCB and kit suppliers like 1776, JMK, etc offer a relay bypass kit that does momentary mode. Like hold the switch in while applying power and it's in momentary mode. Or tap it quickly five times to enter momentary mode. I've been using the 1776 Finish Line relay board when I want relay switching but it doesn't have this feature.

I know Mr Bean offers the VFE switching board that has this feature but it is too big for my intended project. Looking for just the switch and the pcb with microcontroller and associated parts. Don't need the in/out and power jacks on the board.

Any clues?

Hi, it's been awhile since I've attempted to make layouts at home. Since EagleCAD seems to be an Autodesk product now I was wondering if anyone has an older install of EagleCAD pre acquisition that would work on Win7 or even XP. I'm willing to keep an old PC around to just run basic free EagleCAD.

This Univox Micro Fazer does not faze!! I get a slightly quieter bypass signal with no phasing when effect is engaged.

http://schems.com/bmampscom/effects_misc/Univox_MicroFazer.gif

I audio probed down the line of the opamps and I get an awesome phasing sound at the output of all the opamps except the last one OP5 in the schematic. Could someone tell me what DC voltage I should expect at this output? The rest of the opamp outputs have ~4.5VDC on pins 1 and 7 except for that last one it only has about 2VDC.... strange?

My klon seems to sound alright but I'm getting a strange voltage reading on one of the TL072, the other one seems ok. I am using the TC1044SCPA charge pump. On IC1 pin 3 I'm getting a voltage reading that starts at about +3.54VDC and slowly goes down the longer I keep my meter on it. The other side of R2 reads +4.5VDC as expected. Is this normal or should I swap out IC1? IC2 pins 3 and 5 are directly connected to VB rail and both have the expected +4.5VDC.

And on an unrelated note, my +18V line is only reading +16.7VDC... again, is this normal?

Schematic I used : http://imgur.com/DwJq9Gg

Hi everyone, I just picked up a Maestro PS-1A phaser. I rebuilt the power supply with new filter caps and diodes and would now like to try and understand how to properly set the two trim pots. Here is the schematic. One trim is for oscillator amplitude (depth), the other biases the FETs. Other than plucking my guitar and wiggling both until it sounds correct... is there a proper way I can do this with a multimeter and scope?

I understand the oscillator is just slightly modulating the FET bias... and so it would be good to have FETs biased very close to the middle of the operating range... just need to understand how to find that. Any ideas?

I'd like to build a loop switcher with just two loops solely to compare two pedals. It seems simple, one 3PDT to switch between loop out and bypass and another 3PDT to switch between the two loops. Am I missing anything? Better way to do this? Suggestions? 

I'm trying to build a friend a prop for his halloween costume, a basic transponder. One one end a transmitter and the other end would be a handheld responder that beeps with frequency in relation to distance to the transmitter. Is there a textbook circuit for this? Something I could power with batteries on both ends?

Thought this might be a good community discussion. I'm finishing a few different big muffs this weekend and I've never had good luck swapping transistors, always end up back at the usual 2N5088 no matter what variant they are going into. Any effort at sourcing lower gain transistors similar to the coveted transistors in the old Ram's Heads, etc... has lead to really weak sounding circuits.

I'm curious how you all go about keeping project parts lists/boms organized? I have about twenty different partially completed pedals and boards and I'm thinking now would be a good time to decide on one system and stick with it. I know both Mouser and Digikey have built in BOM managers but if possible I wouldn't be opposed to a third party app or hell.. even just a decent method using Excel spreadsheets. Right now I just have a physical folder with printed PDF's of everything I need to finish and then I just go through and highlight the parts I already have with one color and what is needed with another. It gets messy quick.

Does that exist? A soft switch relay based A/B/Y pedal (or even just an A/B). I'm moving away from the blue 3PDT's and would love to have a relay based switcher. Anyone aware of a kit or pcb? Now that I made this thread I'm wondering if three single relay bypass kits/pcbs like the 1776 finish line could accomplish this.