6SN7 Preamplifier (T1105E)

This preamp circuit has a typical configuration as found in a 1946 publication. Supply voltages are indicated.

Power Cut-off Protector (CB17463E)
This circuit, from 1999 documentation, prevents the powered device from receiving power when it...
Timed Voice Photo Relay (CB17041E)
This circuit is intended for monitoring an environment. It fires a relay with a sound, but only if...
Bilateral current source (CB7544E)
Found in a Popular Electronics from the 90's, this circuit uses integrated from that time, today...