Tuesday, November 12, 2019
Morula Auto Wah
Here's a simple auto wah circuit with a pretty low parts count I thought was interesting. Not a lot out there on it, but it uses a single CD4049UBE to create an LFO and wah audio path. The depth of the effect is controlled by the LFO. Should fit nicely in a 1590B. Here's the schematic for reference.
Has anyone ever seen a working version of this circuit? The reason I ask is a few years ago I tried breadboarding something very similar to this and while it worked, I could never keep the oscillator from "ticking"... The only thing that helped was using a separate chip for the oscillator.
ReplyDeleteThat was my concern with this circuit as I was laying it out. I think this vero layout is verified and there was no mention of tick so I went ahead and laid it out.
Deletehttp://guitar-fx-layouts.42897.x6.nabble.com/MORULA-4049-autowah-td47669.html
Did it had ticking noise?
DeleteAnyone verfied it?
Hi, I built this circuit today according to the layout, and verified it with the schematic here: https://www.diyschematics.com/schematics/galleries/Richard-Boop-RLBJR65/album107/Morula_Schematic.gif I have pretty much the same issue: big oscillator thump and a very muffled output. I can get the rate up to maybe 120bpm-ish and then it starts making zipper noises and slows down after that. Possible I did something wrong, of course. Any guidance would be appreciated.
DeleteAnother update: Turns out I had the buffered 4049 instead of the unbuffered. I got hold of the proper chip and it works better, but still not usable. It hits some kind of resonance point in the sweep and just howls unpleasantly. Been over my build a dozen times, I don't think I did anything wrong.
DeleteWell - the PCB does not want to work - I etched it and soldered it, but to no avail - what I do get is the signal from my bass unaltered plus the LFO bleed/click. Checked for shorts - found none.
ReplyDeleteIs this verified or not?
ReplyDelete