Overview
In amateur radio and computing, a boat anchor or boatanchor is something obsolete, useless, and cumbersome – so-called because metaphorically its only productive use is to be thrown into the water as a boat mooring. Terms such as brick, doorstop, and paperweight are similar.
Amateur radio
In amateur radio, a boat anchor or boatanchor is an old piece of radio equipment. It is usually used in reference to large, heavy radio equipment of earlier decades that used tubes. In this context boat anchors are often prized by their owners and their strengths (e.g. immunity to EMP) emphasised, even if newer equipment is more capable.
An early use of the term appeared in a 1956 issue of CQ Amateur Radio Magazine. The magazine published a letter from a reader seeking "schematics or conversion data" for a war surplus Wireless Set No. 19 MK II transceiver in order to modify it for use on the amateur bands. The editor added this reply:
The editor's use of the term generated some reader interest, and in February 1957, CQ published a follow-up story that included photos.
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