R2/T2 Articles John Seboldt, K0JD, Milwaukee, WI Last update: 3/23/04 Rick Campbell, KK7B's, modules and the QST articles describing them: The R1 DC receiver: "High-Performance Direct-Conversion Receivers", August 1992 (online at http://www.arrl.org/tis/info/pdf/9208019.pdf). You still need to read this even if you're interested in the R2 below. The R2 single-signal direct conversion receiver (a kind of phasing SSB exciter in reverse!): "High-Performance, Single-Signal Direct-Conversion Receivers", January 1993 (online at http://www.arrl.org/tis/info/pdf/9301032.pdf) The T2 phasing SSB exciter: "A Multimode Phasing Exciter for 1 to 500 MHz", April 1993 (online at http://www.arrl.org/tis/info/pdf/9304027.pdf) Using these as a 2-meter microwave transverter IF: "Single-Conversion Microwave SSB/CW Transceivers", May 1993 The miniR2 RX board (smaller, less current draw) and a complete 1-watt 20 meter CW station: "A Small High-Performance CW Transceiver", November 1995 The author revisits the noise figure question: Direct-Conversion Receiver Noise Figure, in "Technical Correspondence," February 1996, and describes several significant and excellent mods! Kit Info The basic modules are available as kits (or you can get bare PC boards) from Kanga US. The original R2 is not now available, but the R2Pro and miniR2 are available, and you can get a PC board template for the original R2 article in .pdf format from ARRL