The National TR 56 Mc Transceiver

The August 1933 issue of QST carried the three page article describing a "Tool-Box 56-Mc Transceiver". Within a year National had commercialized the design, introducing the TRW and TRM 56 Mc transceivers.

[Text edited from the 1934 National catalog]

The National Transceiver, as the name implies, is a combination receiver and transmitter designed primarily for portable use on the 56 mc band. Two tubes are employed, a type 30 and a type 33. When used as a receiver, the type 30 functions as a self-blocking superregenerative detector, transformer coupled to the type 33 used as an audio amplifier. When used as a transmitter, the type 30 tube functions as an oscillator and the type 33 as a modulator.

The transceiver is made in two models, the Type TRW self contained in a wooden carrying case with compartments for the various batteries, hand-set, etc., and a compact model, Type TRM consisting of the transceiver unit mounted in a metal case with a three foot cable for connection to external batteries.

Provision is made for using either a single wire antenna, or any of the various doublet or zepp types. The recommended system is the Pickard Antenna, which requires a coupling transformer between feeders and antenna.

Type TRW transceiver in quartered oak case without tubes, batteries or handset  List price $67.50
Type TRM tranceiver in compact metal box without tubes, batteries or handset List price $45.00

TRM 56 Mc Transceiver

Compact version of the TRW 56 Mc transceiver

Inside a National 56 Mc Transciever
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