This circuit by Ferranti, in a 1967 publication, is intended for reading perforated tapes. The circuit uses transistors from the era that can be replaced by modern equivalents.
This filter was found on a 90's Radio Electronics. With the components used the cutoff frequency...
August 2017 - Mouser Electronics is supplying Vishay's new high-speed, high-sensitivity...
This amplifier for public address was found in English documentation from 1967. The transistors are from...