Linear Amplitude Modulator (CB21087E)

Found in an Analog Devices documentation from the 90s, this circuit uses a component of the time, not common nowadays.

Light intensity meter (CB7340E)
This circuit was found in a Philips documentation from 1970. The components are of the time,...
Pulse divider (CB6830E)
This circuit divides the frequency of a 2 kHz signal by 2. The circuit was found in Philips...
Wind Sound Generator (CB21346E)
This circuit was found in an English publication. The components are current, and the transformer must be...