The Haunted House

Thursday, March 22, 2007

Major Morgan the DIY Theramin

A few weeks ago, Amanda did her Ebay thing, and got me an old Major Morgan electronic organ toy. I used to have one of these things as a kid, and they sound bloody awful. Naturally, now that I'm a lot older I want to attack the thing and rewire it.

The concept of the toy is quite simple. You insert cards with colored blobs. At the top of the card is a sequnce of squares. If you play the sequence of squares by hitting the correct blob, you should get a tune. It comes with old chart toppers like, 'This old man', 'Row row row your boat' and other crap like that.

A friend of Mats (called Mat) who is also a fellow toy torturer, recommended I fit a light dependent resister to the Majors head and turn it into a theramin. A theramin, for those who have never heard of one before, is a musical instrument that you wave your hands around like a spaz and the pitch changes. They were invented by Bob Moog. I fitted the LD resister and drilled a hole in the Majors head to mount it.

I stared fitting some switches and a jack output socket, but realised quite quickly that I couldn't fit the bloody things in the case due to the awkward layout of the circuit board. Plus the fact I bought fairly large switches. DOH!!!

Therefore I decided to create yet another breakout box. The cable I had was only 6 core alarm cable. And sods law dictated that I needed 8 core. Typical!!!

Anyway, I just added another cable to the otherside of the major as I'm impatient and don't want to go back to Maplins tomorrow. The dual cable configuration looks quite interesting though as he now looks like he has arms.

Once all this wiring had been done, I mounted all the controls in the box and screwed it all back together. This weekend I will make some recordings of it.

The bends I did were as follows:
1 - Theramin pitch bender with on/off switch
2 - Pitch halver switch
3 - Strangled cat portamento (no seriously, it sounds like a cat being strangled).



  • Small Correction:
    The theramin was invented by Leon Theramin long before Bob Moog was even born

    Or was it the Major Morgan you were refering to ;-)

    By Anonymous Anonymous, at 9:33 am  

  • Outstanding! I've got a few of these things and very much want to try some circuit bending tricks on them. Any specific thoughts or suggestions on what I should try?

    By Anonymous Anonymous, at 5:08 pm  

Post a comment

<< Home