heathkit ta 28 fuzz booster

[digi2t]

I agree with doing the diode thing. Look at the Fuzz E-One at Small Bear and see how Steve did the power supply:  https://www.smallbearelec.com/Projects/FuzzE-One/FuzzE-One.htm

Poifect!!

[Mark Hammer]

I threw one together on perf.  Took all of a half hour.  I used a 2N3391 with an hfe of 330 or so, and a BC308B of unknown hfe (legs too short to make contact with meter socket).  Input cap was .1uf, and 10k resistors to ground on tone control.  Sounded okay - aggressive and hairy - but very sputtery unless you played a chord.

I had used a pair of 1N4001 and pair of 1N5817 in series as my fake zener to get close to 1.5V, and it seems the 5817s did not like that one little bit.  They got very hot.  I'll go back to a trio of 1N4001s and see if that holds up better.

[PRR]

> fake zener to get close to 1.5V, ... got very hot.

What value resistor in series with the zener and battery?

If you put a lo-volt zener right across a 9V battery, sure it will get HOT, and the battery will go flat real quick.

[Gus]

I posted this IDEA in the past for an adjustable 9VDC to 1.5VDC

[Mark Hammer]

> fake zener to get close to 1.5V, ... got very hot.

What value resistor in series with the zener and battery?

If you put a lo-volt zener right across a 9V battery, sure it will get HOT, and the battery will go flat real quick.

Unfortunately, I didn't use ANY resistor, not having looked at the suggested example from Steve Daniels beforehand (  ).  What resistor value would you suggest?

[pinkjimiphoton]

thanks guys, i will look into it and see if i can work it up today while g is at school..

looks easy enough, i gotta run to rat shack and get some 914's tho, i can't believe i am out of 'em.

i DID use it last nite, just to try it out, it's not real dynamic, and seems to suck ALOT of tone out of the signal chain when engaged.

even with the 2 10k's replacing the 1k's in the tone circuit (and i paralleled another 10k under the circuit board on the 10 k feeding the tone stack) it's still not quite ballsy enough.

real close...i may try putting maybe a 2.2k there instead of 5 k.

but that said, it's a much nicer distortion than i expected, very very vintage sounding....pretty impervious to guitar knob changes, but great sustain and a different "sag" than 9 v pedals.

i will try to do the SPT video today while she's at school.

thanks brothers . 

[LucifersTrip]

even with the 2 10k's replacing the 1k's in the tone circuit (and i paralleled another 10k under the circuit board on the 10 k feeding the tone stack) it's still not quite ballsy enough.

real close...i may try putting maybe a 2.2k there instead of 5 k.

try it with 0K (removed or shorted). you'll get way more volume and more high end

[kaycee]

Heres a clip of mine that I did a while back. Probably my Tele on the middle PUP selection, 1st time round both controls halfway, then tone to the bass side, tone to the treble side. Like Jim says, it doesn't turn right off on the fuzz control. I find that it sounds much nicer over the 1st 3rd turn of the fuzz dial, but I'm not into massive distortion, I just like a bit of grit and edge.

http://www.mediafire.com/?e1tz6wvdj3c44gn

Looking at my notes I'm using the 10ks to ground off of the tonestack. I have two of these myself and have sold a couple (one up on ebay at present), one with an LM317T regulator (mostly because I wanted an indicator LED) and one that I run off of battery. Its had the same battery in it for about two years. If I do another it will be battery with a power off switch. If anyone knows how to light up an LED from a 1.5v battery that would be neat   Voltage doubler maybe?

Sounds daft, but I found it hard to fit an AA battery into a smaller sized box, so I build them in these:





Thats the one with the regulator. This is the battery one.

[pinkjimiphoton]

even with the 2 10k's replacing the 1k's in the tone circuit (and i paralleled another 10k under the circuit board on the 10 k feeding the tone stack) it's still not quite ballsy enough.

real close...i may try putting maybe a 2.2k there instead of 5 k.

try it with 0K (removed or shorted). you'll get way more volume and more high end

to my ear, 3.3 is perfect

[pinkjimiphoton]

check the link in this thread about using diodes

here's the vero i worked up...now can run from 9v batt or power supply

[LucifersTrip]

If anyone knows how to light up an LED from a 1.5v battery that would be neat  

there are many ways...as I mentioned earlier in this thread, I use the easiest (they're not super bright but cool enough for an indicator):
http://www.futurlec.com/LED/Red_2mm_LED.shtml

then there's:
http://www.metacafe.com/watch/943296/one_aa_battery_led_lamp/

this:
http://farm4.static.flickr.com/3622/3324388279_83b9a99623.jpg

and this (which looked the best, but couldn't find em in small quantities...haven't looked recently):
http://www.muzique.com/news/not-a-joule-thief/

[Mark Hammer]

So I changed the supply arrangement on mine to the same thing Steve Daniels uses for the Fuzz E-One ( https://www.smallbearelec.com/Projects/FuzzE-One/FuzzE-One.htm ): a 100k resistor and three 1N4001s in series to ground.

The sputter is absolutely gone.  The distortion intensity is toned down a lot, though, so I may opt for a smaller current-limiting resistor as well as reducing the 10k just ahead of the tone control. 

Effective tone control, though, I must say.  Worth exploring for Big Muff users or other circuits using the same sort of tone control.  Sometimes you don't want searing to be replaced by muffled.  Sometimes you just want a little more body without quite as much sizzle.

[pinkjimiphoton]

mark, try a 10k resistor there like in the vero i posted instead of 100k.

i have ZERO change in tone, other than being slightly brighter on a wart than on a battery...the distortion stayed remarkably the same.
i used a 4739 zener or shotke or whatever them things are called. worked like a charm.

i took out the AA battery holder and batt right out of the equation, just hooked up a normal 9v 2.1mm jack, and opted for a 9v battery snap as well as the little daughter board..can run on battery or standard power supply.

it is a lot BEEFIER sounding on 9v imho...probably just because with more power, it's a more stable supply i'm thinking?

i noticed i could overload the AA in it and make it sag some when i was really beating on it.


all that said, a 3.mm led will light just enough so you can almost see it in a dark room at 1.5v.. just a dim glow. but ya don't need a CLR for it.

[Electron Tornado]

all that said, a 3.mm led will light just enough so you can almost see it in a dark room at 1.5v.. just a dim glow. but ya don't need a CLR for it.

Try powering the LED from the 9v section, not the 1.5v.

[pinkjimiphoton]

lol...no worries, ET, i got it powered from the 9v supply. but i DID try to power it from 1.5v..before converting it yesterday to 9v.

at 1.5, it just barely glows...almost imperceptibly!

[Mark Hammer]

100k changed to 10k, and its AOK.  

Removed the 10k just ahead of the tone control and got more output.

The tone is decent now.  Pitted it against the Tonebender Mk III I made, and while it sounds a little different, is every bit as agressive and a little woolier, compared to the Tonebender's "throatier".  I just need to figure out how I'm going to adjust the volume.

Thanks for all the tips, folks.

This past year has been a real Heathkit year/  Last year I bought a TA-16 amp, and a couple months back I bought a TA-17 amp that needs a little bit of work.  And now I have a TA-28 clone.  Sheesh, all I need is a Harmony Rocket and it's 1968 all over again!

[pinkjimiphoton]

mark, try about a 3.3k just before the tone stack...or a 5-10k trimmer...you'll find the sweet spot where with the fuzz control off, it's unity gain, and then you can roll up the filth.

i am really digging this little pedal!!

i gotta thank the guy on ebay for posting it!! lololololol!! 

[pinkjimiphoton]

here ya go, another episode of STUPID pedal tricks...

today's attractive little device is the heathkit fuzzbooster...

[digi2t]

Sheesh, all I need is a Harmony Rocket and it's 1968 all over again!

Mark, shouldn't that read "Hasheesh, all I need is a Harmony Rocket and it's 1968 all over again!"

[mac]

I was thinking that at 1.5v q1 is biased close to 2/3 vcc, but at 9v q1 operating point is close to vcc, ie 8.4v, so I'd expect different distortions in both cases.
Near vcc distortion "looks like" octave up. Just a thought.

mac