This small audio amplifier circuit in complementary symmetry was found in the 1974 Mullard Databook. The output pair can also be the BD135 and 136.
This oscillator with FET was found in Popular Electronics from the 90s. This traditional...
This alarm does not interrupt its operation when the power is cut. A battery is kept at a constant...
This was a very popular instrument in the workshops of the 60s and 70s. It was a "top of the line"...