The transistors of this circuit found in an English 1980s documentation may be the modern BC548 equivalents. The circuit is battery powered and the earphone must be crystal.
Thes astable was found in old publication of 1968. The circuit uses general purpose germanium...
The circuit presented is from the Motorola Linear Databook of 1990. The integrated circuit is a...
This simple digital circuit tester can work with TTL technology when powered by 5 V and with CMOS...