Note
QST, Jul 1979, p. 179.
QST, Mar 1980, p. 156.
QST, Jul 1981, p. 144.
QST, Jan 1982 p. 195.
IRL’s FSK-1000 RTTY demodulator was designed to provide landline-quality copy over radio links. Its circuit used computer-grade components and contained four dozen op-amps. Push buttons selected standards shifts, but the unit was continuously tunable over a 100–1000 Hz range.
References
Review. QST, Jun 1980, p. 44.