Freeze Alarm (CB14454E)

The circuit of a 1968 publication can be implemented with more modern transistors such as BC548 for NPN and BC558 for PNP.

Phase Shift Oscillator (CB4373E)
This circuit was found in an English magazine from 1973. The magazine no longer exists, but the...
1-Transistor MW Radio (CB19180E)
This radio version of 1 transistor, extensively explored on this site and in this section, is from...
Faucet Control (CB21585E)
This dual control was based on Texas Instruments documentation for the CD4050. The circuit has two...