Crawls Backward (When Alarmed)

IconProjects, musings about guitar builds, guitar repairs, vintage tube amplifiers, old radios, travel, home renovation, and other stuff.

Building Jack Orman's Mini-Booster

After finishing up the MM-1 tweed amp, I'm taking on a couple of projects with much smaller parts.  And no tubes!  (Can you believe it?).

First up is the famous (legendary?) 'Mini-Booster' designed and popularized by the great Jack Orman.  This is a 'clean' boost rather than a distortion pedal.

Quite a few modern boost and distortion pedals are based on his designs.  Rather than build it on perfboard, I sprung for a PC board from the man himself.    You can see on the left how small (compared to what I usually build) the whole board is.  The whole thing fits in my hand!

In keeping with my tradition established in This Here Blog, I'm not just going to build it stock.  No sir.  I'm going to add a tone control based on the famous Big Muff Fuzz tone control - but with a Jack tweak.

I have all the parts gathered together.  Instead of one pot, I have three to fit into the box.  Good luck to me.  I just bought a bunch of small (16mm) pots, but only one of them is a value I need.  So I have 2 full-size pots, one small pot, a 3DPT switch, an LED, a circuit board, and two jacks to stuff in there. 

After some trial and error, I come up with a configuration that will work.  I think.

Soldering transistors makes me nervous.  They can be destroyed by high temperature.  If you recall the Cattlegrazer project, I used a transistor socket to prevent damage to the rare and pricey Mullard transistor I used.

Here, however, I bite the bullet and go with some forceps as a heat sink (aka heatsink) for the J201 transistor leads.  I solder them in pretty quickly so I should be ok.

Did I mention how small these parts are?

While I'm inhaling soldering fumes, I am listening to my trusty Hallicrafters S-40B that is my workbench radio.  It lives on its own shelf, hiding behind a rack of tools.  On this night I listened to Radio Bulgaria (a nice music program that runs in the early evening on the East Coast) and Radio China International.

Not a great picture, but the dials are actually green.  Very cool. 

I recapped and realigned this radio 6 or 7 years ago and it still keeps chugging.


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