Quad Chip Tonebender

[petemoore]

I used the NTE Quad Si Gen purp transistors chip in a Tonebender build..
 Thanks J Orman, B Tramblay and RDV for the schematic.
 I measure the gains with the DMM...one side bot Q's were close to 126 hfe and the other side was around 176 Hfe.
 I used the 'low side for Q's one and two, not using the last Q yet [maybe a booster er buffer later thought.
 So it is intense FUzz..do doubt and works, but is slightly constricted on single notes...not exactly gating.
 I took the Pin measurements, perhaps you could take a look at them and suggest where I might want to adjust something? Thanks...
 Battery Volatge: 11.86v...my alarm systems old cells...
 Q1 C  8.83     B 1.34     E .77
 Q2 C  1.38     B  .63      E.02
 Q3 C 10.37    B 1.40     E.80
 The ten K trimpot on Q3 collector is maxxed and that's the lowest V reading I could get there...will mess with that now that I'm reading along...
 Any others that look 'funny'?

[petemoore]

I'm guessing piggybacking lowers collector voltage. [T/F]...get out your metere, Pete and see what you can find out...lol
  I probably will do further  piggybaking tests and implementation, on Q's 1 and 3 a bare 3904 B/E junction added much changed the sound to lower gain, output and treble...of which there is ample amounts of...quite Sizzly the way it sounds as it sits.

[petemoore]

I whipped out some BC's..108 for Q1 and 109c's for 2 and 3/// HOt Tamale's...I may not try another chip against these BC's...a Juicy High Gainer I sezz SiZZlein HOTT...well I put a 5k / 4k7 paralleled [across lugs 1 and 3] variable Resistor, kinda cool building it around a 14 pin IC socket, with an EZ to get to 5 holes left it's 'almost' too bad this thing doesn't need a booster or something to light it up..whew
 If you try this, watch you don't burn your fingers on the strings..they get hot'.
 It might could use some Piggytoning down for use with a big amp...
 I like the GE Tonebender but it's kinda temteraturmental and finicky...just 'different too...very comparable. Those BC's are just dripping nectar juice though...same thing happpened to my Colorsound Overdriver...it lit up with the BC's, but in a more subdued way.

[smoguzbenjamin]

Those strings getting hot because you play so fast or have you just put you guitar down against the radiator?

[Joe Hart]

Do you have a schematic?  I am very interested in a piggybacked ToneBender schematic.  Thanks.
-Joe Hart

[RDV]

Do you have a schematic?  I am very interested in a piggybacked ToneBender schematic.  Thanks.-Joe Hart

If my "Pete Speak" is happening I think he's referring to this http://www.diystompboxes.com/pedals/schems/NPN_Si_TB_Mk.%20II.pdf, but 'piggybacking' the transistors. A good way to start would be using the transistors that I recommend in the PDF and just doubling them up "piggyback" style. I haven't tried it, but I think it would work well. A 10k trim at the collector of Q3 is better than a fixed resistor in any case.

Regards

RDV

[petemoore]

That's the one...
 I would put either a 4l7 + 10k trim, on the last Q's collector, my 10k didn't seem to get the voltage down far enough with the NTE Quad.
 With the BC 109c's in Q's 2 and 3 BC108 in Q1, I simply set the bias by ear, and had range left on both sides of the trimpot 'sweet spot' ].
  No piggybacking. I like the circuit Tops. Juiciest TB yet !
 I've built all kinda FF's and TB's added boosters and buffers etc.  I can unequivically state in starque "Pete Speak" ...lol [ I hope] that this circuit really suprized me.
 Ben I don't follow the guitar on the radiator technique you typed of...perhaps you could explain how that works? Most guitar maintainence pamphlets recommend not exposing the guitar to extremes of temperature and humidity, unless this is quite the effect, I don't think I'd like it...