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Date: | Fri, 13 Jul 2001 09:38:55 -0400 |
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The Allies had something called HUFFDUFF (HF/DF). It stood for,
high-frequency direction-finding. It was developed specifically to
locate NAZI U-boats and later refined to counteract the NAZI U-boat
practice of squirt transmissions. It was a series of fixed DF
(direction finding)
stations that were capable of locating the submarines even though their
transmissions were only a few seconds long. By April of 1944 the
receivers could scan the horizon 20 times a second and "zeroed in
accurately and semi-automatically on any emission". They then
transmitted the location to the nearest hunter/killer group and ASW
(anti-submarine warfare) planes were on location in a very short time.
Often catching the sub on the surface. I do not recall if the accuracy
of the locations was ever stated.
Two examples from David Kahn's (1967) book The Codebreakers (p504). On
30 June 1942 U-158 reported that it had nothing to report. HF/DF
stations in Bermuda, Hartland Pt, Kingston, and Georgetown triangulated
a location. This was sent to an airborne ASW patrol out of Bermuda.
The U-158 was spotted on the surface 10 miles from the intercept
location and sunk. On 5 May 1944 the U-66 sent a 15 second transmission
regarding replenishment. 26 stations picked it up. Three hours later
an ASW plane attacked and forced the sub to dive. An hour later a ship
joined the attack and 25 minutes later the sub was destroyed.
Identifying a ground station would require a more accurate location.
Because you have to get the right building to raid. But the distances
from the DF station to the transmitter would be shorter and this would
reduce the error.
Jamie Brothers
Ron May wrote:
> In a message dated 7/12/01 1:49:27 PM Pacific Daylight Time,
> [log in to unmask] writes:
>
> << but if it was used to transmit signals, you gotta figure that any
> military bases in the area would have had ears out looking for just that
> kind of
> thing - and static ground stations can be easy to locate...
> >>
>
> Not in World War II. You can not equate modern technology with that back 60
> years ago. A quick blast of signal on an odd bandwidth could not be tracked
> in time to catch a clever spy. Heck, spies were transmitting secrets to
> Soviet trawlers off the San Diego coast right up to 1991, when the Cold War
> ended and no one caught them.
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