I
have written often about the many contributions that hobbyists make to various fields
of technology. Often times the efforts put out and methods used by amateurs are
on par with those of professionals; the main difference between the two being that
amateurs do not get paid for their work. This archived BBC video titled "Wartime Radio: The
Secret Listeners," sent to me by longtime RF Cafe contributor Gary Steinhour
documents how the work of two British amateur radio operators, Russell Clark (call
sign THX) and R.J.B. Hippisley (call sign HLX), resulted in a significant strategic
advantage during World Wars I and II. The two hams convinced the Admiralty
that they were able to intercept German communications to and from submarines (U-Boats),
surface vessels, and Zeppelins better than 'professionals' in the service.
After receiving a command position in the Royal Naval Reserve, Hippisley was
essentially granted unlimited funds to establish wireless listening stations along
the coast, whereupon his operators eventually devised means to triangulate signal
origins and thereby locate and track movements of German craft. Highly sensitive
vacuum tube circuits and careful antenna construction permitted angular resolutions
in the neighborhood of less than 2°. Now having strong advocates within the
service of the capabilities that amateur radio operators (including many members
of the Radio Society of Great Britain) were able
to lend to the country's defense efforts, a previously untapped resource of reliable
and patriotic (ensured by proper vetting) technicians quickly grew the force's ranks.
They received the designation of VIs (Volunteer Interceptors). Secrecy was maintained
remarkably well for nearly three decades until in 1941 the
Daily Mirror rag printed an article
titled, "Spies Tap Nazi Code." Fortunately, it went largely unnoticed and did no
apparent harm.
Relatively few spies were discovered amongst MI8 ranks, and those who were caught
were either shot or turned into double agents. Those were the days when survival
of nations depended on decisive action without regard for political correctness.
Many people today, including yours truly, believe that is still the most efficient
approach to security.
Once the Germans figured out that their messages were being routinely intercepted,
they began encoding using methods familiar to radio amateurs, so it was not long
before the MI8 crew figured out what was going on. The establishment of
Hanslope Park in 1941 facilitated
large-scale message interception and decryption activities. German secret service
and Gestapo messages were intercepted in such great numbers that cryptographers
were able to discern the entire network of broadcast stations, and even uniquely
identify German operators by commonly mentioned towns, girlfriends, and families.
This is the kind of scenario by which the old saying "loose lips sinks ships" got
its origin. British intelligence exploited the back door entry into the German secret
service by feeding false information to their operators, one result of which was
the capturing of many spies who would be sent based on disinformation. "Operation Mincemeat"
was a particularly spectacular - if gory -example.
If you have 30 minutes to spare and an interest in communications history, this
film is well worth your time.
https://www.eafa.org.uk/catalogue/5108
Sidebars:
- Notice at around 5:20 on the video there is what appears to me a mechanized
semaphore device that
is signaling along with the sailor. - 'R.S.S.' here is the
Radio Security Service (MI8), not
the present day RSS (Rich Site Summary)
- Notice at 19:15 the slide rule sitting on the desk of the direction finding station
operator. - Hugh Trevor Roper, one of the brainiacs behind WWII efforts, reminds
me strongly of Charles Emerson
Winchester, III, in M.A.S.H.
Posted September 24, 2014
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