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.
The 4007 integrated circuit consists of 4 MOSFETs that can be used separately. The figure shows how...
August 2016 - It can be obtained from Mouser Electronics new operational amplifiers with extremely low...
This circuit triggers an alarm in the event of a power failure. The circuit is from an 80's...