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Does anyone know of a good, comparatively safe etchant for steel enclosures? Ive been using copper sulphate, which is slow, and Im finding it hard to get fine detail, and anything thats not lacquer/or nail polish as a resist, breaks down quickly. Is there anything better that doesnt require a hood/full respirator?

Ive used up my bag of cheap tayda 100uf caps ive been using, so I need to buy another hundred or three, does anyone have any recommendations/favorites? Mouser is making me dizzy.

For this application, low esr doesnt matter, no? I dont often build 1590a, so size doesnt matter. I just dont want to have to worry about their reliability, or failing in 8-10 years.

My google-fu is failing me. Does anyone know of a good source (im in the usa) for a spool of wire that is  the 3 wires that are bound together in parallel, that ive seen in nice builds for wiring off board pots? Or even what its called? I really need to work on the cleanliness of my builds.   

I just got a dca55, and was testing it out, and i have questions about its accuracy.

First off its showing all of my diodes with .05 to .1v higher voltage drop than my DMM. My DMM seems to be giving more consensus readings, eg oa126s around .6v where the dca55 reads .75v, or most germaniums around .25 on the dmm, and .33 on the dca55.

Second, i tested a batch of germanium transistors on brought on a whim  some months back, and they are all showing a leakage of 0.00 ma. The hfes seem reasonable (75, 70, 110, 67, 75, 69, 69, 81, 83, 80, 83, 89, 70, 85, 61, 69, 82, 86, 62, 60.) Now, i know they are IT308v s and i know they are low leakage, but all being 0 leakage is suspicious. And if that is legit, what can you recommend i can build with them. The only germanium transistor projects ive built are percolators and screwdrivers, and these seem appropriate for neither.

Thanks--

Hey, search is failing me, so i was wondering if anyone knows off hand the answer. I have a bag of 50 IT308v ge trannies I brought on a whim, and never did anything with, so I figured i should build a ge fuzz pedal. I never built one (not counting harmonic percolators). I like the sounds I hear from videos of a buzzaround, would these trannies likely work there? and if so what hfes/leakages am I looking for for q1,q2,q3 etc?

Are these germanium or silicon? Ive seen differing descriptions online. Has anyone use them and if so, how do they sound, say in comparison with a oa126?

The Harmonic percolator clone (pepperspray?) build doc, is no longer on the main page, as it was discontinued, but isnt on the discontinued projects page. Anyone have a link to the doc? - i need to etch a few more. 

Hey, Im looking for a self etchable reverb project to work from. Im looking for an over the top reverb for shoegaze/wall of sound type of thing. Does anyone know off hand if any of the DIY projects will do that sort of thing, and/or which of the projects should be avoided in general?

Searching around I found, the rub-a-dub, stage center, ggg d-verb, tonepad fv-1, and the equinox/soltice, are there others?   

I recently built a honeydripper, and it works great/exactly as it should. Im trying to analyze the circuit, im a little hazy on how the vowel sounds are being made, can anyone explain the filter section, or better yet  point me to any resources? (more than, http://www.geofex.com/Article_Folders/ECFtech/ecftech.htm) -- Im working on trying to design a envelope filter to emulate the ehx talking machine open-AH setting. And the poke and hope method of changing values on bread board isnt working so well.

I am having the exact, exact, same problem as in this thread:

http://www.madbeanpedals.com/forum/index.php?topic=8484.0

The nautilus sounds like a crappy distortion pedal, and no envelope filter type sound.
Switching low pass/ bandpass / high pass, effects the tone, bandpass is loudest.

Sweep/Peak/Hi Lo dont seem to effect the sound.
Gain functions, and turning the volume trimpot affects the output volume as expected.

The LED is off with one setting of the range, and comes on, with how hard it is played. Adjusting the gain effects the level it comes on. The other setting of the range does the reverse, the LED is on, and dims depending on how loud one plays.

I used the Macron MI1210CLF-R from small bear. They have an F written on them
I used TL074s, and ICL7660SPCA for the ICs.

Ive remelted and checked all part values twice. I checked for continuity from the top of the board part to the trace, on all connections. And checked that there was no continuity in obvious places there could be a solder bridge.

D2 cathode reads between 3.5v and 6.4v.

Any other troubleshooting advice off the top of your heads?

Does anyone have any luck with the cheapish Russian NPN germanium transistors on ebay? In particular, for a screwdriver-esque type circuit? Im looking at the GT404G, MP35, MP38, etc, anyone try any of these?

Is there a way to determine the forward voltage drop of a germanium diode from a datasheet? All of them seem to state that the forward voltage drop is 1v which cant be right. Im running low on OA126 diodes which I love as clipping diodes, but they seem to have disappeared from ebay, so I was trying to see if there is an equivalent, in the russian D9 series, or other commonly ebay-able and cheapish diodes, and dont really want to order 10 different diodes just to get 10 functionally identical for clipping diodes.

Hi all, I built the cave dweller dub ed, and it sounds great except when I have the dwell pot past half it starts to go into runaway oscillation increasing in volume. Any ideas on the possible cause?

I checked for solder bridges, remelt,  and checked values against the BOM. I built two and they have identical problems. Its not boxed.

I did not implement the mix mod. And left the pads open.  I had to substitute a 27pf cap for C6 (22pf) cause I forgot to order them and it was as close as I could find. I didnt think it was a big enough difference to matter.

(Also, Is there a good resource for the PT2399 based circuits, I understand half  of whats going on from the datasheet, but is there anything more comprehensive? )