60's crystal radio (CB22171E)

Found in an English publication from the 1960s, this circuit uses period components, including the commercial grade coil.

Voltage Relay (CB4151E)
This circuit causes the relay to be energized when the input voltage exceeds the voltage value of...
Differential Amplifier and 15 MHz Low Pass Filter (CB12514E)
The circuit we present is suggested by Linear Technologies (www.linear.com) and makes use of an...
Combined light and dark switch (CB7869E)
Found in American documentation from the 90s, this circuit can be used as a shield with the...