Despite being from a 1969 publication, the transistors used have current equivalents such as BC548 and BC558. The circuit generates signals from 1 500 to 20 000 Hz and 4 scales.
June 2017 - Mouser's new AQZ series solid state relays with switching capacity from 5A to 200V are now...
By activating S1 the relay closes its contacts only after a certain time interval that depends on C1....
The current accross the LED as function of the resistor value is given by the formulas. The...