Gargletron update

[jmusser]

Well, I switched the 51K out for 2 100Ks in parallel, so I'd have the 50Ks in the circuit matched closer. It is up and running, but there's still no vowel sounds out of it. Right now, it is a very crunchy overdrive with one of the best tone controls I've ever heard. The tone is very wide on this, and if someone knew how to strip it off and use it on other effects, it would be well worth your while. It has plenty of amplification, and the volume control on the effect is working, but no matter what you do with the guitar tone controls or pick up selection, there are no vowel sounds. One weird thing that happens, is if the tone is set bassy, the A string will ring modulate enough in a down octave to be totally out of tune, until you adjust the tone more treble. It's just the A string too and none of the other 5, which is one of the weirdess things I've ever heard of. The chip I'm using is a TL062CN, so I don't know if that suffix means "don't use in Gargletrons" or not. The cap I'm calling a 680pf is marked 681, which I'm assuming means the 1 is a 0. The cap I believe is .001, is marked 102, and the SI diodes I used are 4148s. Right now, This thing is a real head scratcher, because I can find no wiring errors. I have the stomp switch wired like all his other effects are. I hope I've assumed something wrong, because I would welcome wrong about now, just to be able to change a component and have this thing work. I'm about ready to use it for batting practice!

[Pedro Freitas]

Don't quit man!
Look for tinny pieces of copper linking two traces in the pcb.
Look for broken pcb traces.
Replace the opamp. Check for EVERYTHING one more time!

I've had some effects making me curse at them and talking
to myself and foaming from the mouth and going nuts  :shock:
Just because of a microscopic shunt on a Veroboard!!! :evil:

Pedro

[Doug_H]

;lkj

[Nasse]

How about disconnecting the 1k resistors and listening the filters one at time and hear if one of them is malfunctioning or tuned to wrong freq range

check resistors values with multimeter

[jmusser]

Well, I know it's not a circuit trace, since it's on perf board. I have had the magnifying glass out, and looking at the chip socket to be sure none of those connections are touching each other, and they're not. There's only about an exacto blade in between them, when you have to solder a circuit board socket on perf board with little hookup wire. Now Doug, you may have hit the nail on the head with the 10K "gargle" pot having to be worked to get that sound. I was kind of thinking that the other night, because of the wide tone differences. I will have somebody work that pot while I'm playing, and see what I get. Now, if that is the case, that will be a whole other thing to deal with. I have never worked with a wah type pedal before, and would have to study on how that's done. Since the drawing never said anything about the sweep being pedal activated, I had to assume it was just like the Phuncgnosis, and was attack sensitive to produce the effect. On a different note, I have been wanting to buy a wah pedal, and have been looking at the Vox Wah on Musician's Friend that they have for around $100.00. This is one subject I know nothing about. on wah sounds, I prefer the "White Room" type of sound, instead of a harsh duck quack like Jimi's Wah at Woodstock. That's OK, but not in large doses (my opinion though).

[Paul Perry (Frostwave)]

I will have somebody work that pot while I'm playing, and see what I get.

I just use a drum machine, but you could use a CD of guitar on repeat.
It is pretty difficult (in my experience) to test anything like this wiht an actual guitar, since it is inherently level sensitive.