If you can find Ray Moore's book on "Transmitters, Exciters & Power Amplifiers 1930-1980", you'll find that there was a number of commercially made rigs (some lesser known) that covered 160 Meters. Manufacturers like ALL-Star, Browning, Collins, Eilen Radio Labs, Elenco, Gonset, Gross, and that's just A to G. Pete, wa2cwa