Thread: Frustrated
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Old 05-18-13, 09:07 PM   #40
Sailor Steve
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Quote:
Originally Posted by CaptBones View Post
I can assure you that an HF radio signal, of as little as 500W at the transmitter, can be received via sky-wave refraction, at a distance of some 6000 miles or more and at a receiving antenna depth (not keel depth!) of 33 ft (10m) or more.
Thank you for that wealth of information. I was an apprentice radioman myself in 1969-70, so you would think I'd have some of that knowledge, but I wasn't in long enough to learn that much, or to retain it after I got out.

Quote:
Originally Posted by BigWalleye View Post
But the German accounts routinely describe receiving messages at 30 meters. In your professional opinion, what was the reason for this difference?
I might be able to help shed some light on that. It was my understanding that the mentioned depth was closer to 20 meters, but I haven't read the same accounts you have, so you may be right. Don't forget that whatever the depth was, it was measured at the keel. The Type VII u-boat is 9.4 meters from the keel to the top of the conning tower. If 20 meters is correct then the recieving antenna at that depth is only 10.6 meters beneath the waves, or about 35 feet, which is in line with what CaptBones gave for the US boats. If it was indeed 30 meters then the antenna depth would be closer to 70 feet, so that does invite questions.
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