Psychtar help please

[tungngruv]

The Uglyface has turned out to be so much fun that I tried Tims "Psychtar". ( Squeels, Gating, Wah, Ray Guns, Bagpipes plus Sitar and Octave from the "Psychtar" would be cool, right?). So I vero'd it up using Torchy's layout and here's what I get: very weak signal but I hear the volume knob working, I hear the switch making a change but no volume, sitar or octave up (as far as I can tell with the weak signal). Also, the LED lit up bright orange before it slowly turned red, then dark.....and the transformer got warm to the touch. The Led also lit up this bright just by plugging in the input guitar cord with no signal (or trannie in the socket??). The only subs I made were using a 2n5089 and wiring up two 1M resistors in series to get close to the 2m2 called for on the schematic. Everything else right by the layout. Like I mentioned earlier, the Uglyface is everything and more Tim claimed it was so I really would like to hear the Psychtar working correctly. Thanks for any help or suggestions.

[jmusser]

Man...something is wayyyyy wrong! It sounds like somehow you have straight nine volts going to the LED. The LED should only light during pick attack while you're in the "octave" mode. The harder you play, the more it lights up. The reason it sounds like this to me, is the fact that you're activating the battery circuit when you plug your guitar in. There's only a billion things it could be. I know it does work to the schematic, I don't know about the vero layout. It sounds like the front end is working, but something is wrong at the output. Have you checked which way your bands are oriented on your diodes? The banded (cathode) side goes away from the transformer. Sounds like at the very least you'll need an LED. I don't think the transformer has a specific way to go in. Since it's a 10K primary and secondary, I wouldn't think it would matter, but I oriented my primary "P" side towards the transistor. This is a great circuit and works like Tim says it does. I wrote a review on it awhile back saying how things need to be adjusted for the best sounding effect.

[tungngruv]

All the diodes are right according to Torchy's layout and I have the "P" side away from the trannie but I don't think that matters. I'm going to go ahead and perf the whole thing  and see what I come up with!! Thanks for the suggestions and I'll post my results.

[tungngruv]

OK, I checked Torchy's  layout to Tim's schematic and all looks OK. I did notice that pins 3 & 4 (pot side/top of transformer) of the 42TM022 transformer are connected through a vero trace as well as 1 & 6 (switchside/bottom of transformer). Also, by looking at Torchy's layout, I'm wondering if there should be a trace cut under the transformer? Any help or suggestions would be appreciated. Thanks in advance.

[Torchy]

I didnt put trace cuts under the transformer on the layout - Ive added them now. Note that you only cut two traces - the centre tap has to go to ground via the trace under the transformer.

[tungngruv]

Thanks Torchy!!!!

[jmusser]

I knew it had to be something like that, because this circuit worked for me the first time I fired it up, and something wasn't kosher with the symtoms you had. So, it sounds like the entire transformer was shorted across from primary to secondary. Yep, that would certainly do it! I believe that it also would put a straight 9 volts to the LED too. You'll love this thing! You can get some nasty distortion wierdness on the sitar side by cranking everything up, and going to the neck pickup. The up octave is the cleanest sounding I've heard on any build that I've done. Turn everything down, and you can get some weird ring mod stuff on both settings (better on the up octave) set to neck pickup. Set to bridge pickup, nice sitar. You get a lot of different tones with the interaction of pickups, guitar tone controls, volumes and sitar/octave switch.

[tungngruv]

Cool Torchy, made the changes and it sounds great!!! I'm using a 2N5089 instead of the recommended MPSA13 and it sounds pretty good. The sitar is wild and the octave is OK sounding. I'm sure it has to do with the wrong trannie. It's defitely a keeper and I'll post results when I get the correct trannie socketed. J Musser, how does this compare to the Jawari? Any comparisons? I have a boatload of J201's!!! Thanks for all the help!

[jmusser]

I never built the Jawari. I had it bagged up and ready to go, and figured I'd never use the Jawari enough to justify building it, so I stole the transformer, and built the Psychtar instead. On my build of the Psychtar, the sitar effect is every bit as good as the Jawari sound sample, if not better. The up octave on my build, is very "in-you-face", but it doesn't have the fuzz to go with it, that say the Simple Octave Up has. It's distortion is so tame in comparison, that it sounds clean. You'll need to use your neck pickup, and roll off the tone controls on your guitar to get the best up octave effect. I was very pleased with myself for building this sitar version instead of the Jawari, especially since up until that time, I had never heard of anyone else ever building it, and there were no sound samples. I wouldn't worry about the J201s, since Tim has a gob of projects to eat them up with :wink: Use one to build his "Jinx" circuit with. You won't be disappointed. That's a real sleeper right there, and is a very unique fuzz. It's like the Bronx Cheer on steroids!