7MHz Transmitter with AVR Soft-keyer abram, March 3, 2019October 19, 2021 In my last post, I went over the design of a Colpitts crystal oscillator design that put out a moderately clean 7 MHz signal. In order to match the output impedance to 50 Ω, an NPN feedback pair (at least that’s what I’m calling it) was designed. While meeting the… Continue Reading