Over a 3 week period during August and September 1984, a propagation trial was carried out between the Admiralty Research Establishment, Portsdown, and Wick in North Scotland. The main purpose of the trial was to compare the performance of the Slow Speed Modem against that of a Morse transmission. The modem was set up to transmit the Field Test Message No. 3 of approximately 5 mins length and with an off period between each transmission of 1 min duration. The morse, recorded on magnetic tape, was transmitted continuously. The trial procedure was for the modem and morse signals to be simultaneously transmitted on 2 different radio frequencies and the switch over to occur during the 1 minute delay of the modem transmission cycle. The radio emission was single sideband modulation and the transmitter power was set to 25 W per frequency to provide a minimum level of reception.
Comparison of 10 BPS modem with man-read morse
Vergleich zwischen langsamer Funkuebertragung und herkoemmlicher Morse-Technik
1985
5 Seiten, 8 Bilder, 1 Tabelle, 2 Quellen
Conference paper
English
Tema Archive | 2000
|British Library Online Contents | 1997
Online Contents | 1997
Adaptive software modem technology
Tema Archive | 2001
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