This is a diagram of a 1970s reel or tape recorder. It is an Italian Geloso recorder, quite popular at the time. The circuit is a reference for equipment recovery.
This time base circuit for the oscilloscope was obtained from an Electronics Now from the 90s. The...
This oscillator circuit with the TLV2474 was obtained from a Texas Instruments Operational Amplifier...
This circuit is from a 1992 publication, but can be mounted very easily today. The circuit is...