This crystal oscillator is indicated for the calibration of IF steps of common radio receivers. The transistor admits equivalent as 2N2222 or BF494. The circuit is from an old American publication.
This control, which may appear in other versions on this site, was found in documentation from the...
We found this circuit in a 1991 Hobbyst Electronics. The circuit makes use of an unusual...
This circuit turns a relay on or off by touching the sensors or by connecting sensors at these...