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Old 16th Nov 2008, 00:06
  #396 (permalink)  
fdr
 
Join Date: Jun 2001
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OTHR Orfordness

didn't work...?

Of historical note only:

Well, the original UK radar trials were conducted at Orfordness with the Radio Research Station setting up from 13 May 1935 on site, under the direction of Sir R. Watson Watt (& Wilkins, Bainbridge-Bell, and Bowen). Initial transmissions were by a transmitter using huge NT46 valves ex navy, at 5,000V input, giving approximately 20-25kW output @ 50mtr freq, which was boosted to 12,000V giving 200kW. The early tests showed echoes from [parts of] Europe over 2,000 miles away. The first aircraft tracked was a Scapa flying boat at a range of 17 miles, on 17 June 1935.

The initial freq selected, 50mtr was expected to give a good return on the dipole resonator of the expected target aircraft wingspan, but due to excessive interference the freq was increased to 26mtr, then 10-13mtr which remained primary radar freq through Round II.

The tactical requirement of the Air Ministry (Dowding) under Tizzard's Scientific Committee's position was to address defense requirements below 100nm. The OTHR effects were identified but discounted as a nuisance at that time.




well before Jindalee was initiated, "woodpecker" interference was received from what was DF'd as USSR on HF freqs, (back in 60's and early 70's), which was consistent with OTHR trials.

ref: Radar Days, E.G. Bowen, Published by Adam Hilger, Bristol UK. 1987 ISBN 0-85274-590-7
Metres to Microwaves, E. B. Callick, Published by Institution of Engineering and Technology, 1990 ISBN 0863412122


Sir Robert Watson-Watt
AAS-Biographical memoirs-Bowen
CSIRO PUBLISHING - Historical Records of Australian Science

Last edited by fdr; 17th Nov 2008 at 06:43. Reason: clarification
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