Hornby Skewes - Shatterbox  [schematic]

Discussion regarding early stompbox technology: 1960-1975 Please keep discussion focused and contribute what info you have...

HS Shatterbox....corrected??? meet the scatterbox...

Postby pinkjimiphoton » 15 Dec 2013, 05:35

an npn ge/si hybrid version of the shatterbox that actually works, sounds decent, and is useful...

with all due respect, and i KNOW that electric warrior traced an actual unit correctly, i built this unit, and frankly, as drawn i was completely unimpressed.... it was pretty useless as set up. so i took a good hard look at this circuit.
here is what i believe is actually what they intended, but screwed up back in the 60's.
this is built, verified, and working as expected.
adjusting tr3 allows you to set the over all volume of the boost from below unity to pretty well above.
the actual transistors i used are in ge npn's from an old heathkit organ, house # r609980243,
q1 hfe 80, q2 hfe 90, and q3 is a bog standard 3904, hfe 210. a ge transistor in q3 gives more of a treble and distortion boost than volume boost.
the footswitch wiring is correct and modified to allow moving the pot to where i believe the proper position in the circuit should have been.
thanks to electric warrior for tracing an original, and leading to this possible discovery.
the one i built, once biased to the "sweet spots" for the transistors i used is a very nice dynamic fuzz, and a good solid boost completely independent.
by moving the swell control after the bypass switch, it's actually useful.
i believe this was the intention of the EE who developed this pedal.. you want a high inpedance input signal...2.2m is good and high.

by moving the 500k swell pot to the input node of the booster instead of the output node of the fuzz, i believe the 2.2m gives a high enough impedance to allow enough signal to get thru the switch, and hit at a high enough impedance at the input of the now moved swell pot to hit the booster section a lot harder... think of it like a tube amp, where you need a grid load resistor going to allow the tube to function.

i'm not savvy enough electronically to explain it any better than this, sorry.

all i can say is try it. moving that pot takes this thing from crappy relatively useless curiosity to an actually useable, toneful pedal that acts as you'd expect a fuzz into a boost to act.

anyways... first attempt with DIYLC, not the best schem to be sure, but i am 100% sure it's right.

consider r7 as optional... i believe it was a dodge HS used to try and compensate for dropping the ball during the design process.
i can see no other reason why on earth anyone would bleed signal across the OUTPUT JACK with a 100k resistor!!
i tried it with and without.. it does smooth the signal just slightly. i wired it not across the jack, but the output node from the .001 cap.

anyways... schematic. stupid pedal trick video and updated veroboard layout to come soon.

peace.
pinkjimiphoton

Image
"When the power of love overcomes the love of power the world will know peace."
Image
User avatar
pinkjimiphoton
Transistor Tuner
 
Posts: 1127
Joined: 12 Sep 2010, 20:03
Location: new world order land (formerly la-la land)
Has thanked: 195 times
Have thanks: 331 times

Re: HS Shatterbox....corrected??? meet the scatterbox...

Postby pinkjimiphoton » 17 Dec 2013, 06:15

ok, vero cuts n jumpers

Image

as seen from the "rails" side

Image

and here's a verified vero, the thing in the video:

Image

stupid pedal trick:

http://www.diystompboxes.com/smfforum/i ... c=105438.0


Link
"When the power of love overcomes the love of power the world will know peace."
Image

For this message the author pinkjimiphoton has received thanks:
joe_pineapple (17 Dec 2013, 10:38)
User avatar
pinkjimiphoton
Transistor Tuner
 
Posts: 1127
Joined: 12 Sep 2010, 20:03
Location: new world order land (formerly la-la land)
Has thanked: 195 times
Have thanks: 331 times

Hornby Skewes - Shatterbox  [schematic]

Postby modman » 27 Aug 2014, 06:50

Some gutshots
Hornby_Skewes_Shatterbox_001_zps383fa2f1.jpg
Hornby_Skewes_Shatterbox_015_zps80995b95.jpg
Hornby_Skewes_Shatterbox_016_zps3d4942db.jpg
Hornby_Skewes_Shatterbox_017_zps416f6bda.jpg
Hornby_Skewes_Shatterbox_018_zps46db5eff.jpg
Hornby_Skewes_Shatterbox_019_zps69633997.jpg
Hornby_Skewes_Shatterbox_020_zps67a58b8c.jpg
Hornby_Skewes_Shatterbox_021_zpsd4a4b873.jpg
Hornby_Skewes_Shatterbox_023_zpse32147d4.jpg
Hornby_Skewes_Shatterbox_024_zps619a8e96.jpg
You do not have the required permissions to view the files attached to this post.
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)

For this message the author modman has received thanks: 7
beedotman (27 Aug 2014, 10:07), Fredenando (29 Aug 2014, 02:16), IvIark (29 Aug 2014, 09:33), pinkjimiphoton (14 Jun 2015, 03:05), rocklander (30 Aug 2014, 07:22), sinner (27 Aug 2014, 07:20), tabbycat (28 Aug 2014, 23:54)
User avatar
modman
a d m i n
 
Posts: 4238
Joined: 19 Jun 2007, 17:57
Has thanked: 2789 times
Have thanks: 484 times

Re: Hornby Skewes - Shatterbox

Postby modman » 11 Apr 2017, 13:48

You do not have the required permissions to view the files attached to this post.
"The whole point of diy is diy. It's not dsoiyathodtr - do some of it yourself and then have others do the rest" (paulc)
User avatar
modman
a d m i n
 
Posts: 4238
Joined: 19 Jun 2007, 17:57
Has thanked: 2789 times
Have thanks: 484 times

Re: Hornby Skewes - Shatterbox

Postby Electric Warrior » 11 Apr 2017, 14:07

modman wrote:https://reverb.com/item/2808081-jhs-shatterbox-fuzz-rare-tonebender-1966-gold-marc-bolan-t-rex


This one is fake.
User avatar
Electric Warrior
Diode Debunker
 
Posts: 709
Joined: 23 Feb 2009, 04:37
Has thanked: 19 times
Have thanks: 78 times


Return to Vintage Stompbox Corner ( ... - 1975)

Who is online

Users browsing this forum: No registered users and 9 guests