Marconi Type HR11 Telegraph Receiving Equipment, serial no. 655259, by Marconi's Wireless Telegraph Co. Ltd., England, c. 1960

The Marconi Type HR11 Telegraph Receiving Equipment represents a very successful design that was in use by Cable and Wireless until the late 1970s for diversity telegraphy reception. This object came from the Cable and Wireless Engineering College at Porthcurno, Cornwall.

Designed for the reception of important radio telegraph communications, Type HR11 was capable of maintaining highly efficient operation under busy conditions. The selectivity, stability and reliability were designed for high-grade performance under heavy conditions. It could receive CW on/off and FSK signals and was suitable for direct reception of an individual channel, forming part of a ‘frequency shift tone’ multichannel transmission, from an independent sideband transmitter.

The receiver was designed for operation in temperate and tropical climates, in normally protected buildings.