Murphy B40D FSK Naval Communications Receiver
  • Power: 110 or 240 volts - 50/60Hz
  • Wavebands: continuously tuneable from 630KHz to 30MHz across 5 switched bands
  • Sensitivity: quoted for voice as 4V @20dB S/N ratio
  • Valve lineup: 14 total:
    • CV138 (EF91);
    • CV454 (EF93);
    • CV131 (EF92);
    • CV140 (EB91);
    • CV2136;
    • CV493 (EZ90)
  • Released: c.1948
  • Original price: many thousands of (but who cared anyway?)

This set is a single-conversion superhet equipped for frequency shift keying (FSK) reception by teleprinter but can also be used as a sensitive general comms receiver. It is truly a 'boatanchor' and tips the scales at 100lbs (45kg)! The main customer for this 'Mighty Murphy' (yes, it was built by Murphy Radio of Welwyn Garden City!) seems to have been the Royal Australian Navy.

The B40 Operator's Manual may be downloaded HERE (24 pages, 430Kb, LizardTech DjVu format)

This set was the replacement for the Marconi CR100 series (Admiralty Set B28) and comes ready equipped with RIS (Radar Interference Suppression) circuitry.

Unfortunately, it is missing its original front panel power connection but is otherwise a good example of a relatively rare military radio.

See my original in-depth article on this set.

Last updated 28th August 2003

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