Variable oscillator for code practice (CB7317E)

This circuit is from Popular Electronics from the 90s. The integrated circuit is not very common nowadays.

Voltage Monitor (CB11028E)
This circuit was obtained from a Hands-On Electronics, an American magazine from January 1987. The...
3-Transistor Commercial Transistor Radio (CB18381E)
This receiver for listening to the TR-23 phone was manufactured in Japan in the 1960s. The circuit is...
Operational 100 Hz (CB14069E)
This astable multivibrator with an operational one at the time was found in the National...