Hey, sorry if this gets asked regularly. But I'm going to build a Super Fuzz :icon_biggrin: and per this effects diagram the pinout of the transistors doesn't reflect the pinout of a 2SC828. So my question is, is the Super Fuzz build diagram wrong, or do I need to twist the two legs of the transistor to make this circuit perform properly with a 2SC828? Another question I have is, does the jumper in the upper left hand corner going vertically connect the first, third, and fifth horizontal strips, or just the first and fifth?
(http://3.bp.blogspot.com/-gLy8HWE7qQs/TyBDc5__vMI/AAAAAAAAAcg/HiPt_bZl5-w/s1600/Univox+Super-Fuzz.png)
(http://pinout-circuits-images.dz863.com/120/2SC828.jpg)
Quote from: limit6 on March 27, 2013, 04:37:15 PM
Hey, sorry if this gets asked regularly. But I'm going to build a Super Fuzz :icon_biggrin: and per this effects diagram the pinout of the transistors doesn't reflect the pinout of a 2SC828. So my question is, is the Super Fuzz build diagram wrong, or do I need to twist the two legs of the transistor to make this circuit perform properly with a 2SC828?
yes.
if you match EBC of the transistor you have to EBC (E to E, B to B, C to C) on the layout, then you're good
Quote
Another question I have is, does the jumper in the upper left hand corner going vertically connect the first, third, and fifth horizontal strips, or just the first and fifth?
if you look at the schematic, you can see exactly what parts connect to each other. look what connects to the 9V
(http://3.bp.blogspot.com/-cBIzyse_wes/T0EHt4QmTvI/AAAAAAAAA88/Y1fbps_nMsQ/s1600/univox_superfuzz_schematic.gif)
the 10uF is not connected to 9V+ in your layout. The 47uF on your layout takes the place of the 10uF power filter (cap from + to -) in the schematic
2SC828`s with this layout - you`ll have to twist the B and C legs to match the layout.
Thanks Lucifer and Digi. @Lucifer, I appreciate the critical thinking exercise. I'm not great at reading schematics but I'm very eager to learn.
Quote from: limit6 on March 27, 2013, 05:19:00 PM
Thanks Lucifer and Digi. @Lucifer, I appreciate the critical thinking exercise. I'm not great at reading schematics but I'm very eager to learn.
the symbols (especially input/output jacks) may be confusing in the beginning, but remember, almost everything else is just lines connecting points to other points...nothing weird. The jumper you asked about is from 9V+. On the schematic, 47K, .001, Q2C, 220K, 10K, 100K, 10K, 100K, etc all connected to 9V+...not the 10uF on the 3rd "strip". That's connected to expander lug 3, so the jumper goes from strip 1 straight to strip 5. edit: the blue dot signifies a connection.
(https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQMAf_y9ZUP-hFzFGLzj2Oisb6SAxK0_IzAe7yOtAt4LTh7gvuxhg)
good luck
if you can get the 2sc828's, definitely do so... this layout i tried building as well, and i did not get it going.
5088's etc don't work well in this circuit... and match the transistors in the octave section closely and you'll get the best octave up!!
dino hipped me to that... amazing difference. ;)
Didn't get it working? Bummer. Now I'm discouraged from using this vero. As for the 2sc828, I already have a bag of a dozen and a half ;D. Which two transistors are used in the octave engine, and how to I test them to see if they match?
Also, I want more of a gnarly, muddy sound. Were carbon comp resistors ever used in Super Fuzz circuits, or were they always carbon films?
Quote from: limit6 on March 28, 2013, 08:55:14 AM
Also, I want more of a gnarly, muddy sound. Were carbon comp resistors ever used in Super Fuzz circuits, or were they always carbon films?
This should answer you question (full page of many Superfuzz variants);
http://d.hatena.ne.jp/Billl/searchdiary?word=super%20fuzz (http://d.hatena.ne.jp/Billl/searchdiary?word=super%20fuzz)
The greatest collection of pedals on the planet, complete with fantastic pictures. If there was any reason for me to go to Japan, it would be to hunt this guy down, and bow to him.
As for transistor gains, I used 2SC828R's, and I followed the gains spec'd in the diagram below;
(http://img4.hostingpics.net/pics/621587MarieGSuperFuzz1.jpg)
As Jimi can attest, they worked out very well. I bought a bag of 100 828's quite cheap, and I easily found the marked gains sorting through them.
P.S. Superfuzz structure is also used in the Honey Special Fuzz. I used the same gains for the fuzz. Sounds great.
always read the threads with the veros people post. not all are verified.
i built two on IvIark's layout. one never passed signal (i tried a plethora of transistors, including the 828's) and the other i finally got to work, but it wasn't right. both were identical, built simultaneously.
i finally gave up and built the old mike livesley vero layout, fired up the first time.
what ya wanna do in the octave section is match the transistors and the diodes as closely as possible. that will help make the octave pop.
you can use high gain transistors, but it won't sound as good.. glad ya got the 828's. it's a fairly easy circuit to fall in love with once it's working. ;)
Ok, I'm going to switch to this vero and picking up a multimeter that measures hfe (I want Q4 and Q5 to measure between 180-200 - yes? These are the ones I want to match?). Only thing I'm doing differently is using OA90 diodes, not OA91s.
Also, just ordered carbon comp resistors from tube depot! Based on the schematic above, it says to utilize a 100k lin, and 100k log pot. I have a dozen 50k lins. Anyone tried the 100ks? Any preferences?
(http://s4.postimg.org/qlnakuwxn/superfuzz_verified_layout_by_mike_livesley_20_12.png)
QuoteI want Q4 and Q5 to measure between 180-200 - yes?
Yes. The closer the match, the more pronounced the octave effect. You could also incorporate a trimmer, like this;
(http://experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noisemakers/Univox%20Superfuzz.gif)
The 10K trimmer labelled "Ocatave Balance". This can take care of any mismatch, or if you wish, you could dial it in to your taste. Your call.
a couple quick notes...
solidhex (fu manchu) gave voltages from an orginal
http://www.diystompboxes.com/smfforum/index.php?topic=64068.0
C B E
Q1 6.01 .66 .117
Q2 8.88 6.01 5.41
Q3 6.23 3.27 2.72
Q4 3.1 1.7 1.11
Q5 3.1 1.67 1.11
Q6 5.75 .98 .361
The original (I think) schematic from Univox site shows 2SC828 in only the Q2 & Q3 positions and 2SC539's in the other.
http://transistor-spravochnik.ru/description/2SC828/17535
Shows min 65 hfe. I have some vintage 2SC828 and they all measure 80 - 130 hfe
http://transistor-spravochnik.ru/description/2sc539/17085
Shows 250 hfe typical. Unfortunately, I don't have any to compare.
These hfe's make sense in the Dr Lamp schematic that was posted. You can see Q1, Q4, Q5 have higher hfe's.
The weird one is Q6. On the Dr Lamp it's lower hfe and solidhex's voltage for Q6C is relatively high (5.75). I did a bunch of tests when I built my first one and you need hfe < 100 to get there. The higher hfe, the lower the collector voltage...I wound up putting a trimmer on Q6 since I could tell a difference when it was in the 4V range rather than 5V and I didn't want to have to choose...
Yeah, Luce is spot on with the observation. Unfortunately the original 2SC828Q's are impossible to find. The only thing remotely close is the R.
2SC828's came in three flavors; Q (130-260), R (180-360), and S (260-520)
Although the R's are a bit higher gain, out of a pack of 100, I was able to find many in the 140 to 150 range, as well as everything in between the R range.
I used R's in my Honey Special Fuzz. The original sports the Q's as well, but I was able to match the R's for my clone. In a side by side test, the fuzz is very close to the original. I believe that the resistors (metal films rather than carbon comps) may have made the balance of the difference.
Just bought some 2SC829's, some B's (70-160), and some C's (110-250). The spec's are somewhat similar to the 828's, so I figure I would try them on the breadboard, and see what happens.
I report back when I have something.
Wow! Thanks everyone for being so extremely helpful. I feel like wizards are bestowing powerful knowledge upon me. With the mike livesley vero, which resistor gets substituted with a 10k trimmer to bias Q4 and Q5?
Quote from: limit6 on March 30, 2013, 01:02:40 PM
Wow! Thanks everyone for being so extremely helpful. I feel like wizards are bestowing powerful knowledge upon me. With the mike livesley vero, which resistor gets substituted with a 10k trimmer to bias Q4 and Q5?
No subs. The two 22K's that normally go to ground, go to lugs 1 and 3 of the trimmer now. The center lug (2) of the trimmer now goes to ground. The trimmer acts as a divider now to balance Q4 and Q5.
Ok, hopefully my last question... on the Mike Livesley vero, all electrolytics seem as though they don't have their orientation listed. I did notice a very slight color band on the caps, all of them facing down except for C8, which has its band facing up. Am I seeing things? Do all negative ends of the 10uf caps face down, and C8 has its negative band facing up?
(http://s4.postimg.org/fythffosd/superfuzz_verified_layout_by_mike_livesley_20_12.png)
> C8, which has its band facing up
It takes a sharp eye to read that program's cap-marks.
You read it right.
C1 and C16 don't correspond though
they're flipped relative to each other
Derringer, are you saying that C1 and C16 are wrong on the vero? Do both negative bands not face down like in the picture? I'm confused by your wording.
yep, that's what I'm seeing
(http://s4.postimg.org/fythffosd/superfuzz_verified_layout_by_mike_livesley_20_12.png)
C16 should be an easy cap to figure since it's the power decoupling cap. It has the "band" side (negative) on ground.
C1 should therefore have its "band" side facing the guitar input and its positive side facing the base of the transistor.
In this picture it does not.
so if i were to try a build from this layout, I'd get a schematic handy and triple check every connection and orientation.
/derp - fixed, thanks PRR
> C1 should be an easy cap to figure since it's the power decoupling cap. It has the "band" side (negative) on ground.
> C16 should therefore have its "band" side facing the guitar input and its positive side facing the base of the transistor.
C16 is power filter.
The dark-side is the negative side.
Caps are marked for the negative leg:
(http://t2.gstatic.com/images?q=tbn:ANd9GcQ8pb0y-3ubOgxr-mtup5FAzBuj_L0mg75so_z06oJT5gFSTq50lw)
C1 is the input cap.
Ah, yes it does appear to be wrong-way. (As you say: Input is nominal zero V DC, we expect Q1's legs to be positive, the + of C1 goes to Q1 and the - of C1 goes to input jack; that's not what's drawn.)
You "can" verify cap polarity, in most circuits, by building it without the caps, poking the cap-holes with volt meter, noting polarity, and stuffing the caps that way. But for more than a few caps, that's tedious and very error-prone; here we have 13.
FWIW, i DID build mike livesley's layout exactly as drawn, and it works great.
i don't have it any more, but it's in the superfuzz shootout on my youtube
I contacted Mike himself and noted C16 and C1, sent him the picture, and he said
"C1/C16 are fine unless you're reading the schematic/layout wrong.
shaded end = negative = cathode."
He then went on to apologize for the layout being so big. :D
http://experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noisemakers/Univox%20Superfuzz.gif
The schematic posted by digi2t above is the only one with the input cap polarity marked, and whatever Mike says (love his vero layouts, btw - his DLS was like the second pedal i ever built), the input cap on that layout is reversed to how it is designated on the schem: The banded end should connect with the input. It will work as drawn, but that's not how it should be.
I'm gonna reverse my C1 asap.
Thank you thank you
yikes, too late to fix mine. :icon_mrgreen:
i'd imagine the only real issue may be having the outside of the cap acting like an antennae by not being connected to ground, right?
Quote from: pinkjimiphoton on April 03, 2013, 04:49:38 PM
yikes, too late to fix mine. :icon_mrgreen:
i'd imagine the only real issue may be having the outside of the cap acting like an antennae by not being connected to ground, right?
I'm not really sure about the potential problems, i know reverse voltage can damage polarised electro's but i don't know whether the voltage here would be enough to cause issues.
i may be wrong, but i think since caps are "open doors" to ac, the only real issue is the outside wrap of an electro is supposed to connect to ground to "shield" the capacitor. i don't think the voltage coming from a guitar could damage it, but maybe after another driver or effect if it's putting out too much power.
still tho, i don't think the ac part is the thing, i think it's whether it can stand up to dc voltage that's more important. if a shield is connected to + and the input is connected to ground, i'd think it would maybe act more like an antennae and pick up noise, instead of sending it to ground.
but remember... i am farrrrrrrrrrrrrrrrrrrrrrrrrrrrr from an ee, and have only rudimentary understanding of this stuff still. at this point i'm kinda thinking of components and networks and stuff almost like effect pedals... to get the desired sound ya hear in your head, by combining whatever effects/components are necessary to find that sound.
like.. certain values of caps "sound" different when ya put audio thru them.. stupid stuff like that, if that makes any kinda sense.
(like much of my life, i stumble upon this brave new world just as it all becomes obsolete :icon_mrgreen: )
> outside of the cap acting like an antennae
No.
An electrolytic cap does NOT like reverse voltage.
It turns into a short.
If the power bypass cap is reversed, acts short, it sucks ALL the power out of the power supply. It typically blows-up. Maybe with a small fart, but I have seen a mini mushroom cloud and a pound of foil-paper exploded inside an amplifer (yuck).
If the input cap acts short: not enough power here to cause explosion. Instead the circuit just won't work right. Q1 Base near ground, instead of up a volt or so, meaning Q1 is cut-off. (Maybe only when you have something plugged into the input?)
All built! ;D Not really working well though. One of the tone switch positions doesn't work and passes clean audio as if the effect were bypassed. The other has the effect but it sounds like the clean signal is just as loud coming through as the effect. Any ideas? Common troubleshoot?
Ugh... dumb. I wired the tone switch wrong. Still pretty clean sounding though. I'm using 828 transistors that have a Q on them (only one had an R). All measured between 140-215 hfe. I just picked all the lowest gain transistors and threw them in, and put two matching 180 hfe transistors in Q4 and Q5. I'm guessing one of two things could be the culprit, the diodes or the transistors. I'm using OA90 diodes. Probably time to socket the transistors and see if I can pump more fuzz into this circuit?
Quote from: limit6 on April 05, 2013, 10:31:16 AM
I'm guessing one of two things could be the culprit
actually, the permutations of things that could be wrong are way greater than just two :icon_biggrin:
the gains of your transistors are fine. This circuit will make gobs of fuzz with a very wide range of transistor gains
Can you post the voltages of the transistors in in the circuit?
Follow this format:
Q1
C =
B =
E =
Q2
C=
B=
E=
...
then someone will more likely be able to assist
I'll run a search on how to measure transistor voltage and report back with the readings. I assume I need to remove the transistors to do this, yes?
Found the stickies. I'll measure all transistors and diodes and report back. Thanks everyone for all your help. :)