I just saw this thread over at Harmony Central. One fine chap has gone to the trouble of shooting some nice pics of his HP.
I can't identify some of the components, there are some odd parts that I haven't seen before, maybe someone here can clarify. Apparently the builder potted the transistors to avoid copying. I read that the transistors are a combo of Germanium and Silicon.
take a boo...:shock:
http://acapella.harmony-central.com/forums/showthread.php?s=744743d30c3b9df98947560e53137ade&threadid=1008997http://acapella.harmony-central.com/forums/showthread.php?s=744743d30c3b9df98947560e53137ade&threadid=1008997 :shock:
what the hell are the strange looking glass thingies(technical term)?
not the germ diodes..... :?
Quotewhat the hell are the strange looking glass thingies(technical term)?
not the germ diodes..... Confused
Exactly what I was thinking.... I'm sure someone will chime in with the answer. Mojo parts I think!!! :wink:
Quote from: nelsonwhat the hell are the strange looking glass thingies(technical term)?
not the germ diodes..... :?
Resistors. Those are probably late 50s / early 60s military surplus.
The transistors are probably in TO-18 cans with those ferrite core looking things glued on top
Thanks Pete.
Watcha figure that lone black component with the green end and the red blob is?
Mojo, I tell ya :wink:
Pretty sure that's a jumper connecting 1k, 20k and emitter of Q1 to base of Q2.
Hey Vortex, thanks for the post. It's really detailed, and that enclosure is in excellent shape. Maybe if my Percolator had those vintage parts in it, it would sound decent! My DIY Percolator has been my biggest dissapointment to date.
Wow, is the battery really held in by duct tape?? Yikes!...
Doug
This has been one of the most fun circuits for me :D I have had good luck with these a trick is after the circuit put a rat filter circuit and than a 470k resistor and build a mini booster on the end of this 8) ....Really cool now with plenty of sustan and gain and a real nice distortion pedal not really fuzz or overdrive......The trans need to be like pnp needs to be less than the npn trans that I have found out :D .....I added and extra germanium diode in series with one of the two.....
Thanks Vortex for the link. Now if we could only see those component #'s alittle better....
Here's a layout based on the pics:
http://aronnelson.com/gallery/MartyBs/hrmoncprolatr
Mine sounds real good as is:
http://home.cfl.rr.com/dbhammond/harm_spec.gif
I can't remember which one of Alf's versions this is. There may be a minor difference but I don't remember what it was. The other version didn't sound right to me. It was more of an "overdrive" than "fuzz" sound. This one gets a pretty heavy fuzz tone when you crank it up. Transistor types are important. I like the 1n46 diodes for stronger output.
Someone who has a real Perc told me mine sounds just like it.
Doug
I like the Harmonic Jerkulator I built from the layout at Home-Wrecker.com. It doesn't have the diodes at the end, but it sounds cool anyway. Mine is pretty brash and bright and somewhere between overdrive and fuzz. Perfect for garage band type stuff. I recall using a Germanium/Silicon pair of transistors, but can't remember which ones offhand.
Mine wasn't that one. I built mine off an old schematic Alf had on his site back about 4 years ago. If I remember, there were two versions of it, and I built the one that had been proven at the time. I don't remember those transistor types being the ones I used. I'll have to check this schematic against that one I built from to see what the difference was, but I'm not remembering a germanium in there either. The way it sounds now, no mod is going to hurt it, that's for sure!
Did everybody see the last guts shot?
http://i14.photobucket.com/albums/a333/mbet/CIMG3335.jpg
That's no ordinary jumper! ;)
also the strange glass tubes might be "coils" of some sort...
phillips seems to have made some with the tl XXX names...
just a thought...
i also suspect thats more than a jumper.
Alfonso Hermida did trace this thing a long time ago. A little reworking of his trace gets us this:
http://users.rio.com/senorris/junk/Percolatorplay.gif
He has the mystery jumper as a 1uf cap.
Looks weird to me...
QuoteDid everybody see the last guts shot?
http://i14.photobucket.com/albums/a333/mbet/CIMG3335.jpg
That's no ordinary jumper!
Hey, if the guy goes to the trouble of potting his trannys, he might make his own funky jumpers!
I admire his creative building /design.
You are right though!
OK! Thanks Dan. Looking at your revision of Alfonso's schematic that leaves us with just one unknown resistor value!
Here's the updated layout:
http://aronnelson.com/gallery/MartyBs/hrmoncprolatr
Marty, just for fun, if Alfonso had a 220K going from Q1 B to C, maybe it is the value going from B to E in the new look?
I just get really lost in circuits with both PNP and NPN trannies. Even just 2!
Good idea. That'd be a good one to try breadboarding. The markings on the photos from HC Forum are something like Tl 196 .... Maybe someone will figure it out and share. OTOH it wouldn't be too hard to just sub till it sounds good. I have no idea what this thing sounds like. My build of Alfonso's Harmonic Jerkulator always reminded me sound wise of that Joe Walsh song "Life's Been Good To Me So Far".
WERENT THERE GERMANIUM DIODES AS WELL :?
Quote from: MartyBThe markings on the photos from HC Forum are something like Tl 196
No, it says 1%.
http://users.rio.com/senorris/junk/unkn1.jpg
The value is facing the board. It would be nice if the guy at HC would post some values...
Stevo, it does have 3 G diodes.
the 1N34's on layout are germanium diodes...
:oops:
Beautiful Dan. I'm convinced. Somehow your re-posted pic is better than my orig download pic.
:)
I PMed the chap at Harmony Central who posted the pics asking him if he might take a second look at the components for us.
Here's hoping... :D
I drew out a schematic of this a year or 2 ago when one came thru for repair.
Here's my schematic w/ a few notes. It jives pretty close to Alfonso's but I have a 4.7K resistor between the clipping diodes instead of a series resistor on one leg.
http://www.ronsound.com/ebay/aimhp.gif
Thanks Ron for sharing the schematic! The pcb shots at HC forum tha Vortex linked to seem to show 6 resistors (plus 2 pots). :?: Can you help decipher the transistor type "CAKK GE6624 USA 1598" ? I'm taking it that its a germanium something-or-other PNP.
MartyB
Quote from: theehmanI drew out a schematic of this a year or 2 ago when one came thru for repair.
Here's my schematic w/ a few notes. It jives pretty close to Alfonso's but I have a 4.7K resistor between the clipping diodes instead of a series resistor on one leg.
http://www.ronsound.com/ebay/aimhp.gif
Ron,
Does the output really come off of the base of Q2 or the collector?
I took it off the collector, as that is what Alf's schems showed. Hmmm... Never tried it off the base...
This is a subtle but important difference.
Doug
In case anyone's interested, there are companies putting out pedals now that seem to be based on some of the ideas behind the Percolator:
http://www.stereoscope.ca/ho.shtml
http://www.pedalgeek.com/cgi-bin/new_shop.cgi?config=&uid=gNlMHAAA1124108378&command=link--us
There used to be a clip of the "Harmonic Overdriver" at their site. I put the clip up on my site so you can hear it. I think it's the older (not "MK2") version. They are either varying the gain control or guitar volume, can't remember. Notice how the character changes as the gain is turned up. My perc does this but I don't think it gets quite as heavy. That's easy to tune with coupling caps though:
http://home.cfl.rr.com/dbhammond/harm_ovdr.mp3
Doug
Quote from: Doug_H
Does the output really come off of the base of Q2 or the collector?
I took it off the collector, as that is what Alf's schems showed. Hmmm... Never tried it off the base...
This is a subtle but important difference.
Doug
That's what I've got on mine. I think I removed the transistors and checked the pinouts with my B&K tester, but it's been so long I may be mistaken.
Quote from: theehmanQuote from: Doug_H
Does the output really come off of the base of Q2 or the collector?
I took it off the collector, as that is what Alf's schems showed. Hmmm... Never tried it off the base...
This is a subtle but important difference.
Doug
That's what I've got on mine. I think I removed the transistors and checked the pinouts with my B&K tester, but it's been so long I may be mistaken.
That's pretty interesting. I'm going to sim that and try it with mine. I suspect the output vol would be lower, coming off the base.
Doug
Wow, I just simmed it and it looks like a 20db boost if you take the output from the base. I didn't expect that... Not sure how accurate the sim is, but it definitely warrants giving it a try.
Thanks, Ron!
Doug
EDIT: Never mind... Tried it last night and the output definitely needs to come off of the collector.
Any further developments on this? Doug H?
No, other than I suspect taking the output off the base is a typo.
Doug
That thread from Harmony Central had a couple of additions. The poster graciously carefully read out all the readable markings on his component side. AFAIK the only true unknowns left are the values of the trannies (and whether our assumptions on Q2's orientation are accurate) and that weird-looking component in the center that has been accused of being a 1uF cap. I think the DIYers will have this before too long. I'll update my layout in the gallery. (My own build is waiting on a coupla parts).
MartyB
Hi Marty,
I'm ickystay at HC. Here's the pcb for the one I built. The black parts are confirmed, the pink- guesses, and the purple are what I used. The pcb is for pos photo etch and would need to be reversed for PnP. The 1uf np was a tight squeeze.
http://users.rio.com/senorris/junk/perc-try.gif
I used a metal can silicon (BC108B) for the Q2 and a 2SB77 germ for Q1. Had to cover the BC with shrink wrap because when it touched the germ, it shorted out. Maybe the original potting is just to avoid shorting?
Good luck with your build!
Hey Dan!
Sweet layout. Just about a postage stamp! One clue you probably hit on is the visible leads from the photos. They're gold and in a triangular, as opposed to a linear arrangement. They are round wire instead of flat, like most new manufacturing. Based on the size of the tranny pics, I've also been playing with a buncha old trannies. I'm gettin some nice creamy distortion that my jerkulator really never got. Here's a pic of my unboxed build:
http://www.freewebs.com/martyb/harmonicpercolator.htm
I'll post a soundclip soon!
MartyB
Nice layout. I'm going to do this asap...actually #2 on list. Even though it's a quick, small build I know it's going to turn in to a long project swapping every component 1000x....COOL!
Okay see if this link works:
http://webzoom.freewebs.com/martyb/harprc.mp3.zip
It's a sound sample of my build. First two twangs are my tele straight into a small tube amp. Next is with the HP full throttle. Cheezy lick stolen from a cool song by Jim Weider called "Bigfoot".
Quote from: Dan NHi Marty,
I'm ickystay at HC. Here's the pcb for the one I built.
The 220k in the upper left-hand corner should go from the base to the collector.
Doug
Quote from: MartyBOkay see if this link works:
http://webzoom.freewebs.com/martyb/harprc.mp3.zip
It's a sound sample of my build. First two twangs are my tele straight into a small tube amp. Next is with the HP full throttle. Cheezy lick stolen from a cool song by Jim Weider called "Bigfoot".
Weird, Marty... Yours doesn't seem as gainy as mine:
http://home.cfl.rr.com/dbhammond/Brick.mp3
(The tonefrenzy clip doesn't sound as gainy as mine either...?!?)
My clip is through a clean amp, lead tone is a humbucker, rhythm is single-coil turned down to 5. The pedal is at max gain with the volume around 2:00.
Maybe it's super-sensitive to pickup types or something???
Doug
Doug,
The sound level on mine gets alittle boost, but not much. A crazy thing is that there are various orientations of both transistors that still pass an audible signal, resulting in different sounds - like heavily-gated blooming, squashed sounds. Did you play with this at all? I'm pretty happy with mine as is, though I used Si for Q1 and Q2. If we could only peel off those wraps on the trannies and peek....
8)
I used a 2n404a Ge for the first stage and a 2n3565 Si for the 2nd stage.
Doug
Doug, I went from the perculator posted at HC. There is an unknown value resistor in that spot, so I guessed 220K. Look at the gif Marty posted. It could only go base to collector if you flipped the transistor, or if the transistor has a different pinout. I appreciate your feedback, but I'll stand by my layout.
Of course, I just woke up and the world is still a blur.
Marty, thanks for the photo and the sounds!
Dan
Quote from: Dan NDoug, I went from the perculator posted at HC. There is an unknown value resistor in that spot, so I guessed 220K. Look at the gif Marty posted. It could only go base to collector if you flipped the transistor, or if the transistor has a different pinout. I appreciate your feedback, but I'll stand by my layout.
Hi Dan,
The schematic I used is linked on the first page of this thread. I developed it from some schems that Alf had posted a few years ago. He reversed them from some real percs he worked on. There seems to be a lot of variation in the details in different schems I've seen show up. And there are suggestions that the "real" ones varied somewhat.
In the end I don't really care what's "real" or not. :D I built something I really like the sound of and use. If everyone who builds one likes it, that's all that matters AFAIC. :D
Doug
[/quote]Hi Dan,
The schematic I used is linked on the first page of this thread. I developed it from some schems that Alf had posted a few years ago. He reversed them from some real percs he worked on. There seems to be a lot of variation in the details in different schems I've seen show up. And there are suggestions that the "real" ones varied somewhat.
In the end I don't really care what's "real" or not. :D I built something I really like the sound of and use. If everyone who builds one likes it, that's all that matters AFAIC. :D
Doug
Quote
Amen! 8)
Who can argue with good tone you're happy with? :D Also wanting to know this mythical pedal better (without the $$$ expenditure) and what exactly it can do has been part of it for me. I built at least one of Alfonso's versions and came up with a different sound than my most recent attempt at this. Doug, one guy builds a by-the-book fuzz (or amplifier, or guitar), and the result for him is "fuzzes sound like this." Another guy builds a different fuzz, maybe biased differently, different transistors, filter caps and his idea of a fuzz sound is unique. The original paperwork that came with the HP is posted on the Theremaniacs site:
http://pages.prodigy.net/chuckcollins/harmonic.jpg
The specifics about how, and to what degree the different fundamental harmonics are augmented is really interesting. Could this sort of thing be measured with an oscilloscope you think? Audio spectral analyser?
Quote from: doug deeper on August 14, 2005, 04:25:48 PM
also the strange glass tubes might be "coils" of some sort...
REALLY old post... just for people reading this now...
those are diodes.
The mystery ended with this version. There was another thread "Harmonic Perkolator" with John Greene and George Giblet in April 2007; can't find the link,
https://www.diystompboxes.com/smfforum/index.php?topic=68649.20
Here's the original thread,
https://www.diystompboxes.com/smfforum/index.php?topic=55987.0
And the 2007 schematic,
http://www.fredric.co.uk/misc/HarmonicPercolator.sch.png
There's plenty of tweaks out there.