This circuit for receivers was found in an American documentation from the 90's. The circuit operates at up to 500 MHz. The integrated circuit used is uncommon nowadays.
This sensitive 4-transistor signal follower can be used in both audio and RF circuits. P1 is a...
This circuit for powering TTL and even modern microcontrollers is from February 1987, Radio...
This amplifier of a few watts of power was found in English documentation from 1995. Power...