QST, Jul 1965, p. 133.
QST, Mar 1966, p. 127.
QST, Feb 1967, p. 125.
Swan’s Mark I linear amplifier ran 2000 watts PEP with a pair of 3-400Z tubes in grounded grid. DC input on CW was 1000 watts. It had an internal 117/220 VAC power supply and an antenna changeover relay.
