1987: The Two-fer kit schematic

The schematic for QRP ARCI's Two-fer transmitter showed what made this little rig tick: an MPF102 variable crystal oscillator followed by a 2N2222 buffer stage driving a 2N3553 final amplifier. A 2N3906 was used as a keying transistor. Of course, the rig's design two decades ago met FCC regulations for spectral purity at the output. But that would not be the case today. For an enlarged view, doubleclick on the image.