The Marconi coherer was the first ship-to-shore receiver ever made, but within a few years it had been rendered obsolete by the advent of the magnetic receiver. Many were broken up and sold for parts, although some were retained on ocean-going merchant ships and liners, such as the Lusitania, until the Great War. The Norfolk vendor had purchased this example for a few bob during the 1920s – little did he realise that it would fetch the highest price ever paid for a wireless set at auction.
The coherer was the small cylindrical glass tube filled with iron filings. On the reception of an electrical impulse from a transmitter on the shore, these filings would jump into line and connect the current to complete a circuit and instruct the morse inker. The coherer on this example had retained its original vulcanised clamp (which many have not) and also its original metal cabinet (a safeguard against sparks) which it is believed the other example in the Marconi museum does not possess.
Measuring 221/2in deep by 8in wide by 71/2in high (57 x 20 x 19cm) and impressed ‘MWT Co.Ltd, patent MMSS21242’ to the coherer, this rare instrument was contested by over a dozen bidders, eventually falling to an American collector at £35,000 (plus 10 per cent premium).
A price that makes auction radio waves
UK: “ONE of only two known examples of Marconi’s first commercial wireless set in complete condition”, was how this inconsequentially appearing box was described by the English trade underbidder at G.A. Key’s sale in Aylsham, Norfolk on May 4.