Articles / Tech and DIY

Reader Creates Replica RCA Theremin As Gift For Retiring Colleague

Replica RCA theremin by Frank Blöhbaum

With friends like these, who needs to win the lottery?

Frank Blöhbaum, a reader from Germany, sent us these pictures of a replica RCA theremin he built as a retirement gift for a colleague's 40 years of service with their company.  His friend, who happens to be an avid collector of antique radios and measurement equipment, out to be quite proud of Mr. Blöhbaum's creation!

Paying special attention to detail, the replica has the same look and feel as the original RCA AR-1264 and "the circuitry is 95% like the original". 

Of course the parts and the wiring follows the original as close as possible: power supply using rectifier tube, choke input and paper capacitors only; mica compession trimmers; coils having the same dimension as the original and so on. The tubes are a bit different: 36 instead of 224 and 2J27L instead of 120 (better availability), 1626 instead of 71A (better stability for volume oscillator, better availibility).

Click on the thumbnails below to see larger versions of the photos.  As you can see from the pictures, the front and back of the instrument were made of clear acrylic in order to allow the performer to see the craftsmanship inside.


According to Mr. Blöhbaum, the instrument has approximately a 4 octave range and performs similarly to original RCA theremins. You can judge for yourself in a YouTube video here.

From my perspective, this is a incredibly well executed replica, especially given the complexities of the project. Hats off to Mr. Blöhbaum!