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pretty amazing what soundwaves can do!

so, with all the being insideness at the moment, my minds been wandering a bit. years ago i learned about Sonoluminescence, and it blew my mind.

just been looking again at how to do it at home, and the principle is simple, but the gear and knowledge isn't!

however, there are now lots of cool online calculators to help narrow the parameters down to make it less laborious.

so, i was thinking, could one use a £20 signal generator (as opposed to a lab signal generator) a small tl702 based amp, (instead of a lab spec one) and then stick on a transducer. with the goal that this could be built into some sort of sweet coffee table centerpiece where you have a star in a jar!

maybe getting the whole thing onto one pcb, with the transducer attached for ease of assembly?!

so, wanted to try to put a angry charlie with an xotic ep booster, but with the ability to switch the order of the effects on a 3pdt. i had some proto pcbs made awhile back, and with the virus had a bit of time to populate the boards.

its pretty decent, however, i cant turn the narosla boots control all the way up, or the turnabouts gain without crazy crazy squealing oscillation and all kinds of terrible noise going on. its is a bit better when its turnabout into the narosla, but to be honest both ways are pretty unusable atm!

ive pretty much just stuck one infront of the other and managed to get the 3pdt working, but either the gain in the stages is way too much, or ive got some huge feedback loop problem as these two should work fine together, shouldnt they? schematic attached and some voltages.
ic1 is tl072, q3 is 2n5457 and q4 is 2n5088, and its on 17v charge pump supply. VB is actually the 5v coming off a regulator chip too, not 15 volts!
IC 1 1-5v
       2-5
       3-4.5v
       4-0v
       5- 5v
       6-5v
       7-5v
       8-17v
Q3   14v drain
       250mv source
       0 on gate
Q4 17v on emitter
     9v on base
     8.5v on collector

hi guys, so, built myself a clone of the gtc 'bloody finger' overdrive pedal. works pretty well, but there is a strange dead spot from about 8 o'clock to 12 o'clock on the tone control .fully left the sounds perfect, but as you turn it the sound becomes pretty lofi/crackly, before sounding like a starved transistor, to then nearly silent , before doing the reverse . tried 4 different pots, so can eliminate that, and checked the transistors, all good there. solder joints all good, and built this on 3 different pcbs, all have exact same problem! used this schematic https://www.pedalpcb.com/product/chromedome/. but layouts different . weird thing is, in that zone on the tone pot, if you touch the shaft, the crackling dies down quite a bit, even when its out of the enclosure ,i.e not chassis grounded . is this something to do with this inductor/transformer tone control interference ! and quiet playing comes through , but harder string hits result in absolute silence until the tone control is moved. weird!!!

these are them, if anyone recognizes them from the photo?!

https://www.google.co.uk/search?biw=1920&bih=974&tbm=isch&sa=1&ei=p2dPW4T1PKyNgAaotbO4Cg&q=way+huge+pedals+gut+shot&oq=way+huge+pedals+gut+s&gs_l=img.3.0.35i39k1.3259.4029.0.5065.5.5.0.0.0.0.84.334.5.5.0....0...1c.1.64.img..0.5.330....0.34spxVDkpdw#imgrc=zMKyEv4It-s2MM:

hi guys, anyone know the part number / brand of idc connectors that are used in way huge pedals nowadays? look like molex, but cant figure out!

cheers, all the best

hi guys, well given up on the rustbucket pcb i acquired, no idea what the problem is with those smoking resistors!

ive built up a harbinger one, and it sounds sweet as. only thing is i feel the top speed is a little slow. found a couple of mods- changing the 4k7 resistors to 2.2k/3k3, and the 2m2 to 5.6m, but the bulb (using an led) stays on. tried switching q11 to a 2n5457 with the pinout switched around, but still no joy, almost seems slightly slower than stock values....?

i understand that there's a point the transistor will stop switching, but still seems a little slow in my mind and compared to some samples ive seen of other univibe effects.

also have a small problem in that if i go all the way slow, then it takes a few seconds when turning the speed back up before it starts oscillating.

any tips of values to trying changing around a bit? few people mentioned playing around with the cap values in the lfo, but i obviously dont want to burn my board out as its the only one ive got!

cheers for any advise!

So tried the half watt resistor idea, but same smoking. So to try and get some voltage readings I pulled all the ic from their sockets. Voltages looked OK, but as I put the ic back on one by one as soon as I got to ic 7 and 8 the smoke started again, guess I've found the area to continue looking!

ideal, cheers for the info, will give it ago! cheers

reflowed the joins around that area, but dont have continuity between r46 and ground. i do how ever between r46 and ic13 and pin 8, and between r46 and c13, which is 100uf and connected to ground.

whats the purpose of r46 as 22r seems a bit of a strange value?

annoyingly i cant plug it in long enough to get voltage readings as im scared ill burn the traces up off the board!

hi guys, been lurking here for a month or so now, but been busy with work to get on with some building. so, hi!

randomly found a pcb for the rust bucket on ebay a few weeks ago (along with some other boards) and ordered up the parts to solder them on.

however, once i plugged it in, my 1/4watt resistor at R46 started smoking and burning up!

ive checked over for cold solders, wrong values etc, and all seems ok, power supply was 18v, and even tried a 9v battery and the resistor continued to smoke out.

any idea what could be happening?! tried a max1044 as well as the lt1054 for ic13 with the same result... smoking r46!