SWTPC Psych-Tone Composer Synthesizer

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"This is a very vintage and VERY RARE (try and find another one!) "Composer-Synthesizer" made by Southwest Technical Products Corporation (SWTPC). This was sold as a kit (thus the homemade appearance) and promoted in the July 1971 issue of Popular Electronics.

Very few have survived, and even fewer in pristine condition. This one is not prisitne but it appears to be all there. It DOES make "tones" through the built in speaker and also outputs to the RCA jack when plugged in. However, I would hardly characterize it as "clean" (or very loud) sound. Some of the knobs and switches work, some don't. The "tune" sequencer works (proving that at least some ICs work) and changes the order and pattern of tones. The frequenty and pitch knobs seem to work, though again, the sound is nothing you would want to record! The circuit board is OK but appears to have been worked on and the soldering is nothing to be proud of, but hey, these were made by kids like me back then! The wiring is certianly a rats nest. It appears that somewhere along the line, the front panel was cut away and each wire was soldered to the corresponding wire coming from the circuit board. These solder joints are mostly in free air, and I re-taped them all before plugging it in. Whoever built it used sockets for all the IC's and most of the transistors so you can easily replace them if you wish. Many of the switches have combinations of resistors, diodes and capacitors dangling from the terminals, presumably to create tonal variations."