FOR OFFICIAL USE.
MERCHANT SHIPPING-WIRELESS TELEGRAPHY.
Automatic Wireless Calling Devices.
Report by the Admiralty
on tests of
Automatic Wireless Calling Devices
carried out on behalf of the
Board of Trade and General Post Office,
1923-1924.
LONDON:
PRINTED & PUBLISHED BY HIS MAJESTY'S STATIONERY OFFICE. To be purchased directly from H.M. STATIONERY OFFICE at the following addresses: Adastral House, Kingsway, London, W.C.2; 28, Abingdon Street, London, S.W.1; York Street, Manchester; 1, St. Andrew's Crescent, Cardiff;
or 120, George Street, Edinburgh;
or through any Bookseller.
1925
Price 3d. net.