Wien Bridge Oscillator (CB7474E)

We found this circuit in a 1977 Radio Handbook. The lamp is the critical component, being 120MB at the time. Transistors support equivalents.

Proximity Voltage Indicator (CB4645E)
This circuit indicates whether a cable or wire is energized by simply approaching its antenna. The...
1 kW synchronized switch (CB9266E)
Found in a 1967 RCA documentation, this circuit can be made with equivalent SCRs according to the...
Unit Gain MOSFET Amplifier (CB6128E)
This Hughes circuit is from 1968. Equivalent modern components can be used. The input impedance is...