4093 Sine Square Converter (CB26335E)

Found in a Popular Electronics from the 90s, this circuit operates up to about 5 MHz input.

Antenna Amplifier (CB17130E)
This signal booster that ranges from long waves to about 30 MHz is recommended to be used with...
Frequency Divide-by-10 TTL - Circuit Using the 7490 (CB253E)
TTL square signals can be divided by 10 using this circuit. The maximum frequency depends on the...
50 KHz IF (CB22243E)
Used in 1950s CW receivers, this type of circuit used germanium transistors. The circuit has...