Recently I found a bunch of guitar related things on the curb during my town's yearly junk day. There was a couple of small practice amps, Fender tuner, Realistic amplifier, cables, ect. Unfortunately, it was all in a five gallon bucket full of stank swamp water. Yeah, that was frustrating.
Anyways, I took the lot home, disassembled it all, and gave it a scrubbadub with a hose and a bristle brush out on the sidewalk. Amazingly, I got it all working.
One of the practice amps I found was a TS PG-3 Overdrive. It's one of the generic 3w amps you see with names like First Act, Ammoon, Aroma... The speaker was ruined and I wanted the 386 power amp for another project, so I dissected the overdrive circuit and built a pedal out of it. I added a switchable voltage doubler for fun and it worked pretty well.
Below is the schematic I drew up from the OD and the box I put it all into. The box is wood, originally a 80's Polo gift box with a slide-out lid. I covered it all in black patent leather and used the corners and rails from a busted storage box to dress it up a bit.
And one more pic.
Wow, nice job! What a cool idea.
Damn yo, you win teh intertubz for today!
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I'm glad ya'll liked it. I gave the pedal away but it was fun to mess around with while I had it.
If anyone has one of these PG-3 amps, please take a moment and see if yours has the value of the unknown capacitor listed on my schematic. All mine had was the polarity marked.
Also, does anyone know a source for the L channel rails I used on the box? I found the manufacture online but they only sell it by the ton ($2,100-$2,500). I don't quite need that much...
Are you state-side?
Yes, I am in TN.
You are a better DIY man than me. I would have looked at the stank swamp water and kept on walking. ;D
This is really impressive. I admire your ability to see beyond the 'junk' and create something fantastic. Kudos.
I suspect the pin out of the transistor is different from how you drew it here. From the spec, the pins are 1=E, 2=C, 3=B. As drawn, it looks like you interpreted them as 1=C, 2=B, 3=E. I redrew the schematic with the revised pin out and it makes more sense now as a two stage amplifier into a twin-T tone control and volume.
Yes, this is two years old, but I've done a lot of mods on these amps and stumbled into the thread.
Here is my redraw of the schematic. I have not opened up the amp to confirm this, but a two-stage NPN preamp should look like this... Also, the unmarked capacitor is likely a 0u01 based on the similar Marshall schematic which this one is probably copied from.