Found in a 90s Elektor, this circuit makes use of general-purpose transistors, except T4 that can be replaced by an equivalent.
Found in a 90s 303 Circuits, this circuit uses the KTY10 sensor, widely used at the time. | Clique na...
This circuit was found in an English magazine from 1973. The magazine no longer exists, but the...
We found this circuit in an old Argentine publication from the 1970s. The transistor can be the...