This is where I’ll be making available a variety of technical datasheets and technical articles on both current as well as vintage/obsolete equipment. It’s not intended to be a comprehensive resource, just a collection of hard-to-find schematics and datasheets that might be of use to someone wanting to either fix old kit, or homebrew something.


The Transistor Universal Amplification Company (TUAC) were a manufacturer of sound and lighting modules that enjoyed huge popularity in the 70s and 80s. They gave cash-strapped hobbyists and would-be DJs access to high powered amplifiers for very little outlay. While not hifi or particularly sophisticated, they were robust and reliable.

100 Watts was a big deal in those days and TUAC must have manufactured and sold thousands of the TL100 and TL125 (125W) modules. They had a low component count and a novel transformer coupling between the driver and outut stages. They ran off a standard 40-0-40 suopply.

Here’s the TUAC TL100 Schematic

As well as power amps, they produced a couple of preamps, again with a minimum component count. The neat thing with this was it’s FET input stage – you could match it to any signal source, just by changing an input resistor. The VA06 had bass, treble and volume. The VA08 added a mid control.

Here’s the TUAC VA06 – VA08 Schematic