4049 Oscillator with Mark and Space (CB24857E)

With mark and space adjustment this circuit was found in November 1984 Radio Electronics. The base frequency depends on C1.

1 Hz Flasher (CB6796E)
Found in a 1964 General Electric documentation, this circuit uses PUTs that are not currently...
Telephone Tone Generator (CB13935E)
This double tone generator uses a specific integrated circuit, having been found in a 1977 CMOS...
Sharp Cut Filter (CB6732E)
Found in American documentation from 1968, this circuit has an acute cut-off of the frequency to...