# The Strange Bastard Boost



## Chuck D. Bones (Dec 15, 2019)

I've had it in my mind to build a Range Master style boost for a while, here's the final result.  I borrowed elements from the LovePedal Church of Tone and the Catlinbread Naga Viper.  It started out with a single NPN Ge transistor gain stage.  I did not like the way it loaded the pickups, Humbuckers or single coil.  It lacked sparkle.  I tried putting a buffered bypass pedal (DS-1) in front of it and the sound opened right up.  So I added a FET buffer at the input.  What I ended up with sort of resembles an EQD Crimson drive, only with the CoT's variable gain/bias control and the Viper's variable treble boost.  Since the JFET was not in the original vero layout, I had to cram it in wherever it would fit.  The 1M anti-pop resistor ended up on the stomp switch.  Anyway, here it is in its final form. How about that aqua blue LED?





Here it is pre-wired, just before the board went in.  I have quite a few Mammoth pots left in my stash!  The Tayda boxes are powder coated on the inside as well.  I made sure the pots and jacks all have tooth washers to bite thru the paint.





I had to alter the outboard wiring a little bit when I added the buffer.  Not shown: I insulate the board by wrapping an old business card around it.





The CLIP switch disconnects the diodes for clean boost.  The TONE pot rolls back the bass when turned clockwise.  The GAIN pot varies the gain from 5dB to 36dB.  Because the GAIN pot also varies the bias, it makes the scratchy noise when turned.  With CLIP off, this pedal is capable of over 6Vp-p output.  I added C8 to smooth out the distortion when CLIP is on.  Because the diode clipping is asymmetric, I added C6 and R8 to remove any residual DC in the output waveform.  A variety of JFETs and Ge transistors will work in this circuit.  For the gain stage, I used a Russian MP38A.  Any low-to-medium gain Germanium transistor will work.  The one I used has hFE = 65.


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## Mourguitars (Dec 16, 2019)

Very cool CDB !

On that board do you solder paths  on the backside of the circuit to tie everything together ?

Mike


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## Chuck D. Bones (Dec 16, 2019)

No, it's a Vero-style board.  Here's a pic.  Note the circular cuts that separate segments in some of the rows.  In the lower right corner, I deliberately jumpered two rows together.  This pic has a solder splash in it that accidentally shorted two segments.  See if you can spot it.  If I'd done a better job inspecting my own work, I would have found it _before _installing the board and powering it up.


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## Mourguitars (Dec 16, 2019)

on the bottom left 4th row up 4th joint in going down to the 3rd row ?


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## Chuck D. Bones (Dec 16, 2019)

Nope.  It wasn't really a fair question because you have to tilt the board back and forth to see what's touching and what's not.  It's the 2nd & 3rd row from the top, 4th hole from the left.


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## Mourguitars (Dec 16, 2019)

Chuck D. Bones said:


> Nope.  It wasn't really a fair question because you have to tilt the board back and forth to see what's touching and what's not.  It's the 2nd & 3rd row from the top, 4th hole from the left.




Ok i seen that as well, so those boards are sensitive to those over splash solder huh ?


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## Chuck D. Bones (Dec 16, 2019)

There's no solder mask, so one has to be careful and inspect thoroughly.  The clearances aren't any closer than the board we build here, but solder mask makes a huge difference.


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## cooder (Feb 13, 2022)

How did I miss this?!?
On the to do list...


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## Joshhr (Feb 13, 2022)

Out of curiosity, what’s the purpose of the resistor in the 3pdt switch?


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## cooder (Feb 13, 2022)

1 Meg pull down anti pop resistor at input. Would typically be on board when space available.


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