Infrared modulated transmitter (CB7247E)

This simple Philips circuit from the 1960s can use any general-purpose transistor. The signal is modulated at 2.7 kHz.

Random Neon Flasher (CB4541E)
I found this simple circuit from an English magazine from 1984. The circuit can be easily...
Radiation detector (CB8660E)
Information about the high voltage transformer and the detecting circuits was not given in this...
Voltage Calibrator (CB22214E)
The purpose of this circuit is to supply a direct reference voltage from the power grid. The...