https://declassified.library.utoronto.ca/files/original/35dad164a914243e568fff8f596b2e82.pdf 27b56d5b17b0d17d3e479d462ce4dde2 PDF Text Text Document disclosed under the Access to Information Act ~ v l Document divulgue en vertu de la Loi sur I'acces a {'information! „y 'ft'- y : '• *' * URGENT • Hanslope Park, Nr. BLETCHLEY, Bucks. flef. DP.1066. 25th. July, 1947. To:- Director of Signals, Canadian Army Headquarters, Qttowa. From:- Director of Special Communications. During the last few weeks it has become increasingly difficult to pass traffic over the HYDB& circuit. The difficulty arises partly from the severe fading experienced by the frequency of of 15,510 kc/s. at present in use, but it is principally due to heavy interference from an unidentified station transmitting frequency-shift signals on the same frequency. The optimum frequency for this service during the next few^months is predicted to be approximately 20,000 kc/s.. It would considerably improve the speed of message handling, therefore, if you could possibly arrange for a frequency in the range 18,000 kc/s. to 20,000 kc/a. to be allocated for immediate use, to your station VDL1; and for a nev/ frequency in the 15,000 kc/s. band, but clear of 15,510 kc/s., to be allocated for use later in the year when propogation conditions have changed. We are well aware that reception at Hydra is rendered difficult by our own low transmission frequency of 14,520 kc/s. and we aot expect soon to have available a frequency in the 17,000 kc/s. to 18,000 kc/s. band. 'tMfe-E^ 000178 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Hydra Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Identifier An unambiguous reference to the resource within a given context HY00042 Title A name given to the resource [HYDRA traffic issue] Date A point or period of time associated with an event in the lifecycle of the resource 07/25/1947 Source A related resource from which the described resource is derived Hydra Communications - Policy, RG24, 1250-36 Vol. 1, Library and Archives Canada (LAC) Creator An entity primarily responsible for making the resource Department of National Defence Rights Information about rights held in and over the resource Canadian Crown Subject The topic of the resource DND, DCS, radio communications Description An account of the resource Letter from E.F. Maltby, Director of Special Communications (UK) to Wrinch, D Sigs regarding difficulty passing traffic over HYDRA circuit due to severe fading and heavy interference at 15,510 kc/s frequency. Suggests 20,000 kc/s will be better frequency. Publisher An entity responsible for making the resource available Canada Declassified Type The nature or genre of the resource Text Format The file format, physical medium, or dimensions of the resource PDF Language A language of the resource en