Found in American documentation from the 1980s, this circuit has a throughput of 700 Hz and a flat response of 400 to 500 Hz, with crystals of 3 MHz. Crystals of 2 to 15 MHz can be used.
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...