This circuit was found in a 1967 Electronics World. The circuit uses components of the time that are difficult to obtain, such as the transformer.
The trip circuit for this alarm is given in CB16765E. The circuit uses common components and acts...
This circuit is from an old American publication from 1970, but it can be assembled with a BF494...
This circuit found in 1969 Popular Electronics is used to power a gas laser. The circuit produces...