Here's a collection of vero (stripboard) and tagboard guitar and bass effect layouts that we have put together covering many classic and popular effects in growing numbers. Many of these have been posted on freestompboxes.org, so check that site out for great discussions on building your own effect pedals. Enjoy the builds and please also visit us on Facebook and Twitter
First post of the new year. This comes from a request posted in the forum. Not much I could find about this other than it's a Fuzz Face derivative made in the 70's in the USSR.
Sorry for my english and for my little knowledge of electronics. What should I do about that "-9V"? I would like to power the pedal with a power supply but I don't know how to connect it to the pcb. I guess I don't have to connect tip to negative and ground to positive. my only solution is to use a battery by plugging it in like OcularDawn says? And in this case how can I connect the led? Thank you all.
From what I found theirs 3 different versions of those transistors. Since this is a Fuzz Face derivative you should be able to throw any PNP transistors you’d use for a Si Fuzz Face without issue.
actually, it may be a challenge: http://www.5v.ru/ds/trnz/kt349.htm if you look at the table there are three version of these. Most important column is h21Э i believe. Markings on originals are usually just colored dots.
If you look at the gains for each of the transistors you’ll see KT349A 20-80hfe, KT349B 40-160hfe, and KT349C 120-330hfe. This is similar to what you’d expect from other transistors commonly used in fuzzfaces like BC108. The letter designates it’s gain ranges when they were sorted by the factory (low, medium, high) while those without a letter were unsorted and could be within any of the ranges.
Again, since this is a fuzz face based circuit I would expect that any pair that would would throw into a regular fuzz face to he fine here. So expect the differences you’d find if you put a high gain set vs a low gain vs “grail” pair.
Under challenge I mean its not clear what exact transistor modification was used. Originals become unobtanium because of golden-covered legs - most of them were recycled...
the original transistors are still available on eBay. really the transistor type shouldn't matter all that much being that this is a fuzz face derivative, but the gains will have an impact.
was able to run it with 2n2907a transistors (hfe ~300) with some small issues: 1. it mutes if guitar volume knob at 10 - should to reduce volume; 2. at fuzz knob at max there are some high frequencies go thru. No taming caps were used. will try to find less gainy tr
sorry for flooding, but i've a got original kt349a by chance. with a stupid low hfe at 42-46 this thing sounds best! good cleanup, good articulation on the bridge. At full gain it sounds differ than FF, more on the distortion side. So, its alert for owners of very low gain GE or SI transistors. This circuit is for you. I'm not a big fan of soviet stompboxes, but this one will complement Inta Wah pedal from the same series.
A bit late for the party. Built it (npn version, 2n2222a, sounds nice), but I only reach unity volume when vol pot is almost maxed. Anyone experiencing the same thing?? Any solutions within the circuit? (Without putting a boost after it)
Ok, I did a lot of experimenting with this circuit, and finally came up with a great fuzz. First I built it according to the layout, but with flipped polarities for NPN. Nope! Splatty and weak. Next, flipped back to positive ground and messed around with 2n3906 and 2n5087. Noisy Oscillation! Then I read through comments and referred to the original schematic; those resistors should be 47k, so I put those in. Interestingly, not much change. Finally, I started mixing ge and si PNPs. The winning combo for me was ge Q1 (2n1309) and si q2 (2n5087). I hope this helps some other folks with this. Happy building!
Yes, I followed the schematic and used 47k resistors. It’s still a little touchy, and will oscillate occasionally; I think it’s the ge transistor being affected by temperature. I just finished another one, using the same transistor combo, but with a 50k volume pot, 100n output cap and a 2.7 resistor in place of the 6.8. Still some oscillation at full volume, but also very reactive to guitar volume and tone knobs. This whole circuit is very similar to a fuzz face, so there is more experimentation to be done!
Summing up: I prefer the lower resistor in place of the 6.8k. I also prefer the combo of the 50k volume pot and 100n output cap, which yields a tiny bit less bass. 47k in place of 470k as per original schematic. Low hfe Ge in q1. The pedal sounds great now with no noise issues. Thank you for the layout!
Welcome back, Zach! Thanks for the post.
ReplyDeleteYeah second that welcome back ✌
ReplyDeleteJust what the doctor ordered, a simple quick build for boredom!
ReplyDeleteThis comment has been removed by the author.
DeleteAll ready for testing and then I realise it's MINUS 9 volts and I don't have the pre-requisite power supply or the IC to build an inverter... D'oh!
DeleteOh well, I've been meaning to build a voltage inverter and need to order some other parts anyway. :D
You could use a 9V battery...
DeleteFor a negative voltage?
DeleteBlack battery wire to 9v and red battery wire to ring lug of (stereo) input jack.
DeleteSorry for my english and for my little knowledge of electronics.
DeleteWhat should I do about that "-9V"?
I would like to power the pedal with a power supply but I don't know how to connect it to the pcb. I guess I don't have to connect tip to negative and ground to positive. my only solution is to use a battery by plugging it in like OcularDawn says? And in this case how can I connect the led?
Thank you all.
Any suggestions for a KT349 replacement? I couldn't find any for sale and precious little information about its specifications.
ReplyDeleteFrom what I found theirs 3 different versions of those transistors. Since this is a Fuzz Face derivative you should be able to throw any PNP transistors you’d use for a Si Fuzz Face without issue.
Deleteactually, it may be a challenge: http://www.5v.ru/ds/trnz/kt349.htm
Deleteif you look at the table there are three version of these. Most important column is h21Э i believe. Markings on originals are usually just colored dots.
If you look at the gains for each of the transistors you’ll see KT349A 20-80hfe, KT349B 40-160hfe, and KT349C 120-330hfe. This is similar to what you’d expect from other transistors commonly used in fuzzfaces like BC108. The letter designates it’s gain ranges when they were sorted by the factory (low, medium, high) while those without a letter were unsorted and could be within any of the ranges.
DeleteAgain, since this is a fuzz face based circuit I would expect that any pair that would would throw into a regular fuzz face to he fine here. So expect the differences you’d find if you put a high gain set vs a low gain vs “grail” pair.
Under challenge I mean its not clear what exact transistor modification was used. Originals become unobtanium because of golden-covered legs - most of them were recycled...
Deletethe original transistors are still available on eBay. really the transistor type shouldn't matter all that much being that this is a fuzz face derivative, but the gains will have an impact.
Deletei have two BC108A?
Deletedo you think it will works?
Only if you reverse the polarity of the circuit. To build it as is you need PNP transistors.
DeleteCould you reverse polarity of caps and put npn w/out problem? Use whatever npns you want?
ReplyDeleteThat will work.
ReplyDeleteWith that output cap I imagine it has a ton on low end.
I’d try it out. I like 100nf output caps like in the Fulltone ‘69 personally.
DeleteSo you would lower the output cap? What would be a reasonable cap value?
ReplyDeleteFinally new post
ReplyDeleteyyyeeeeaaah
ReplyDeleteglad that the blog lives!
just found a demo of original for curious people https://youtu.be/AUBY1q8pJfM?t=67
ReplyDeleteZach, there is a typo: both 470K should be 47k
ReplyDeleteand input cap should be 100n instead of 1u
ReplyDeletelayout has been updated.
ReplyDeletewas able to run it with 2n2907a transistors (hfe ~300) with some small issues:
ReplyDelete1. it mutes if guitar volume knob at 10 - should to reduce volume;
2. at fuzz knob at max there are some high frequencies go thru. No taming caps were used.
will try to find less gainy tr
Here I thought everybody had run away! I'll have to try this if you can get hold of the parts!
ReplyDelete10u cap positive pole should be in G row.
ReplyDeleteno, why? but 10u should not be connected to q2 collector for sure - it goes thru 30k. will update my build, thanks
Deletewould still like to see a true vibrato like the vb-2 or malekko vibrato
ReplyDeleteThis comment has been removed by the author.
Deleteforum->requests is your friend. vb-2 was refused by IvIark 5 years ago. Malekko vibrato is hacked small clone.
Deleteupdated
ReplyDeleteYou can tag it, Zach. YAFF. Switched to 2n2145 with hfe around 160 for both (rotated at 180 degrees).
ReplyDeleteThanks for keeping blog alive!
sorry for flooding, but i've a got original kt349a by chance. with a stupid low hfe at 42-46 this thing sounds best! good cleanup, good articulation on the bridge. At full gain it sounds differ than FF, more on the distortion side. So, its alert for owners of very low gain GE or SI transistors. This circuit is for you. I'm not a big fan of soviet stompboxes, but this one will complement Inta Wah pedal from the same series.
ReplyDeleteSlav, did you finally remplaced 470k resistors to 47k?
Deleteyes, I did. All works fine in my build. Didn't notice that Zach omitted it. You can check schematics following link to the forum.
DeleteThis comment has been removed by the author.
ReplyDeletehttps://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html - i have a printed copy of this on my workbench
ReplyDeleteWould a 2N3906 work for this?
ReplyDeleteit's sounds better if you remove the 6.8k resistor, even though the resistors should be 47k, not 470k,
ReplyDeleteBuild with 2n2907 and works...
ReplyDeleteToo much low noise, but noise desappears with knobs at Max, there sounds decent...
Why has this 47k not 470k resistors not been corrected?
ReplyDeleteThis comment has been removed by the author.
DeleteIs 47k
DeleteLook:
http://guitar-fx-layouts.42897.x6.nabble.com/Anta-Fuzz-circa-1974-td45854.html
My build drops volume, any suggestion to solve the problem? thanks
ReplyDeleteA bit late for the party. Built it (npn version, 2n2222a, sounds nice), but I only reach unity volume when vol pot is almost maxed. Anyone experiencing the same thing?? Any solutions within the circuit? (Without putting a boost after it)
ReplyDeleteOk, I did a lot of experimenting with this circuit, and finally came up with a great fuzz. First I built it according to the layout, but with flipped polarities for NPN. Nope! Splatty and weak. Next, flipped back to positive ground and messed around with 2n3906 and 2n5087. Noisy Oscillation! Then I read through comments and referred to the original schematic; those resistors should be 47k, so I put those in. Interestingly, not much change. Finally, I started mixing ge and si PNPs. The winning combo for me was ge Q1 (2n1309) and si q2 (2n5087). I hope this helps some other folks with this. Happy building!
ReplyDeleteThanks for your comment, i played a lote with this schematic too. Did you lkeep on board the 47k resistor with those transistors?
DeleteYes, I followed the schematic and used 47k resistors. It’s still a little touchy, and will oscillate occasionally; I think it’s the ge transistor being affected by temperature. I just finished another one, using the same transistor combo, but with a 50k volume pot, 100n output cap and a 2.7 resistor in place of the 6.8. Still some oscillation at full volume, but also very reactive to guitar volume and tone knobs. This whole circuit is very similar to a fuzz face, so there is more experimentation to be done!
DeleteSumming up: I prefer the lower resistor in place of the 6.8k. I also prefer the combo of the 50k volume pot and 100n output cap, which yields a tiny bit less bass. 47k in place of 470k as per original schematic. Low hfe Ge in q1. The pedal sounds great now with no noise issues. Thank you for the layout!
Delete