This circuit was found in 1980s Radio Electronics. The circuit includes the power supply. The ICL8038 circuit was very common at the time in this type of application.
This circuit was found in a 1967 Raytheon manual. The transistors are from the time. Equivalent modern...
This circuit was published in a 1979 magazine, but it can still be easily assembled as the...
The circuit presented generates short pulses. This configuration was found in a publication from...