Telephone dialer (CB8521E)

Using an integrated circuit from the time, we found this configuration in a 90s Radio Electronics.

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Negative Regulator 723 (CB5463E)
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This circuit was obtained from a 1967 General Electric manual. The circuit uses components of the time,...
Temperature controlled oscillator (CB7528E)
The thermistor used in this circuit must have a resistance at room temperature between 10 and...