The SAM Speed Control was made by Simprop, a manufacturer based in Germany and one of the pioneers in radio control systems. This electronic speed control is one of the early units of the pre-FET era, released around 1980 – 1982.
Simprop actually was known for their high quality radio control systems used for model airplanes, but they also sold products for radio controlled cars. The SAM Speed Control was developed for 1/12 scale cars and 6 cell battery. Beside forward drive, there was a dynamic brake and a BEC system. Specs were 20 amps continous and 40 amps peak power. You can see a large heatsink mounted to the powertransistors, this was essential for any early speed controls as this technology was generating more heat than the FET type ESCs later.
We found this ESC was popular in Italy, also have seen reports at French and German magazines.