Joe's Decade distortion ... anyone built one ? .... Awesome :D

[MartyMart]

http://www.diystompboxes.com/smfforum/index.php?topic=32415.0

Here's the original thread/schem from a year ago, it's taken me this long to get to it !
( sorry Joe )
I have it 90% there, but have the following :

1- lots "o" hisssss
2- 2 pictures of the pot wiring, I've used the one above which seems backwards
3- With pot at minimum ( max ) total cut out of sound, pot's also quite noisey when adjusted.
4- A very wierd bias, as per the schem, Ge NPN at 4v giving a very "hard" sound overall.

Just wondered if anyone's sorted one out ?
Many Thanks,
Marty.

[MartyMart]

No worries, just got it working perfectly, had a bad trim pot, one solder
bridge ( miniscule . ) and used J201's
J201's @ 6.6v ( used 50k trimmers )
OC140 Ge NPN collector ( or emitter depending on how you look at it ) @ 4.6v ( tuned in with new 50k trimmer )

Fabulous Joe, great "amp-like" tones using the tone stack and gain controls
from clean through to "edge of breakup" and on to "Big Muff" sounds too 
Really great sounding circuit .....
I wish that I had made it a year ago !! 

MM.

[markm]

Marty,
U got a layout for it??

[MartyMart]

Marty,
U got a layout for it??

No, not really, just stuffed in onto a piece of stripboard 10 strips x 28 holes.
It's not a tough one, only three trannies
It could be "neater" but it works !
..... quite a few pots though !

[markm]

I was just wondering as I have been trying to develop some of my own layouts......
I'm not overly successful yet but, I will be eventually I hope!

[MartyMart]

I was just wondering as I have been trying to develop some of my own layouts......
I'm not overly successful yet but, I will be eventually I hope!

Go for it !!
Check my Joe Davisson "Vulcan" layout in my gallery, against the schematic
You'll see exactly what's going on, I don't "twist" the circuit that much, just
schem from left to right --> stripboard left to right
So long as you make all the connections and cut the strips as you go, it's not
hard ... well if I can do it then anyone can .... right ! 

MM.

[jmusser]

Marty is this tone on the order of the Vulcan or Blackfire, or a little more tame the those? I must have missed this one along the way.

[markm]

I was just wondering as I have been trying to develop some of my own layouts......
I'm not overly successful yet but, I will be eventually I hope!

Go for it !!
Check my Joe Davisson "Vulcan" layout in my gallery, against the schematic
You'll see exactly what's going on, I don't "twist" the circuit that much, just
schem from left to right --> stripboard left to right
So long as you make all the connections and cut the strips as you go, it's not
hard ... well if I can do it then anyone can .... right ! 

MM.

Well, actually I've been trying to develop my own to etch although, I have traced a couple of the Veros and made
circuit boards with them. In fact, I think one was yours!!
Thanks Marty!!!

[Ry]

I put an OC44 from Small Bear in the GE position on mine.  It's way more 'open' than with any of the other Ge's that I had sitting around.  If you have the means, I highly recommend it.

Ry

[Dave_B]

Maybe I missed it Marty, but did you modify the pots like Joe did?

[MartyMart]

Marty is this tone on the order of the Vulcan or Blackfire, or a little more tame the those? I must have missed this one along the way.

It's a little more tame, but it's got a very BIG and open sound, just seems like you have a big amp
when it's on  !!
Sounds like a good Jfet sim & a good fuzz in one

Maybe I missed it Marty, but did you modify the pots like Joe did?

We did a "trade", Joe sent me the special pot and I sent some goodies ... good old fashioned "Barter" !

I put an OC44 from Small Bear in the GE position on mine.  It's way more 'open' than with any of the other Ge's that I had sitting around.  If you have the means, I highly recommend it.
Ry

The Ge is supposed to be "NPN"  !
An OC140/CV7112 is very close to OC44 but in NPN form, I have a nice one, gain 110 hfe and no leakage in there ...

[Ry]

The Ge is supposed to be "NPN"  !
An OC140/CV7112 is very close to OC44 but in NPN form, I have a nice one, gain 110 hfe and no leakage in there ...

Yeah, you're right .  I must have bought the NPN transistor above the OC44 in the Small Bear stock list and used that.  It was more than a year ago...