ELECTRA DISTORTION

[Renegadrian]

It is my next project, breadborded and I like its sound...
btw I saw there are 2 layout and compared to another schem I saw HERE...

dragonfly layout

R1 2.2M
R2 4.7K
R3 3.3M
R4 470
C1-C2 0.1 µF


markm layout

Ra 1M
R1 470
R2 4.7K
R3 2.3M (?)
C1-C2 0.1 µF

The added electro should be some kind of filtering, I guess...

- dragonfly R1 and markm Ra are some kind of pull downs? They also have different values...
- dragonfly R3 and markm R3 is the resistor between C and B - better a 3.3M or a 2.2M?
- dragonfly R2 and markm R2 is the resistor coming from the 9V - same value here 4.7K
   I read someone using 39 or 47K here...why that big value difference???
   HERE a 47K is used
- dragonfly and markm both have a 470, HERE a 680 is used
   Again, which is best???

Anyway, I like the sound of this electra!!! 

[frequencycentral]

Hi Adriano! The Trotsky is also based on the Electra: http://www.beavisaudio.com/projects/TrotskyDrive/

[Renegadrian]

Yeah, looks cool, but I just haven't got the right parts,  while ED main components are ready in my bin...

Found this at GGG
another layout
Some components differ again...Mainly that res. from 9V...

[Renegadrian]

And THIS seems just too similar...In fact it's just another variation of the original...

[Barcode80]

resistor from 9v is for filtering, value is not terribly typical. The pull downs are pretty irrelevant past 1M, any 1M or greater will be fine, probably most just put in whatever they grab first.

dragonfly has the gut shot in his gallery, so i would wager his is closer to the real thing, but if markm made one it sounded great, i can assure you. both will work.

[Renegadrian]

Yeah, looks cool, but I just haven't got the right parts,  while ED main components are ready in my bin...

Was wrong, maybe I'd give it a shot...Seems a nice variation of the original!!!

[Dragonfly]

[Barcode80]

Here is a Q&D layout

[Dragonfly]

and....

[Renegadrian]

Thanks my friends, I already knew those other schems/layout you posted (not the last one) in fact I have a folder in my PC named "Electra and variations" (which are Dano Trotsky and IIbe). I just wondered why there are some differences among all those Electras, so I started breadbording and finally I gave birth to another variation, using a 2n5089 and adding a pol. cap to have more gain...I'll post the layout I made if I got back the connection at home (I am at work right now...)

[Renegadrian]

resistor from 9v is for filtering, value is not terribly typical.

Well, I found that it has some influence on the amount of gain, I started in my enhanced version with a 3.3k as per the Trotsky going to the 4.7k, trying a 47k too.
the last one gave a "sputty" sound, like a bad fuzz...I finally put in a 10k.

[frequencycentral]

"Electradrian" - Like it!!

[Renegadrian]

[Dragonfly]

Wont work - you're missing a trace cut between C3 and C2...without it, the electro, output cap, and diodes all short   

[Renegadrian]

The + leg of the electro cap is soldered to the second row starting from the top, so no shortings....

[Dragonfly]

The + leg of the electro cap is soldered to the second row starting from the top, so no shortings....

aaahhh.... i see

I hate mounting electros like that...its more "solid" if you use a jumper and solder the cap to adjacent tracks...unless youre using axial electros of course...

[Barcode80]

resistor from 9v is for filtering, value is not terribly typical.

Well, I found that it has some influence on the amount of gain, I started in my enhanced version with a 3.3k as per the Trotsky going to the 4.7k, trying a 47k too.
the last one gave a "sputty" sound, like a bad fuzz...I finally put in a 10k.

after looking at the schem, it is a bias resistor, so you are right, you can definitely change a lot of sound there. if you replace with a pot, it is all at your fingertips...

[dan5150]

Funny. The Electra from Justin Phipott's site http://www.geocities.com/CollegePark/Library/1355/sites.htm was my very first build ever.

I thought it was cool that I drew the PCB with a Sharpie and everything. :-)

-Dan-

[petemoore]

  Long ago I built many 1 transistor distorters.
  Isn't this the one that does some of octave down on the low string [with everything else 'correct'] between ~A and E ?

[doug deeper]

heres my version!