Bletchley Park Visit - October 2010.

CARS were invited by the Baddow and Galleywood Branch of the U3A to join their coach party to Bletchley Park as were persons from Maldon, Danbury & Chelmsford.

A number of Members took up this offer including John Strange, M0VRS and Wife Virginia, Colin Page, G0TRM and Wife Joan, Clive King, M0GHH, John Robson, G3HMQ & Chairman John, G8DET.

The weather forecast for the morning was severe rain and the meteorologist were correct - it poured.   Stan's - our coach company were able to pick up 10 persons from the West Maldon Community Centre by driving in so the transfer took place without anyone getting wet.

By the time to coach got to Danbury the rain had slackened for another 10 persons to get aboard and finally stopped by the time the remaining 28 persons got on at Great Baddow which we left at 9am.

After a comfort stop at South Mimms and slow traffic up the M1 we arrived at Bletchley Park at 11.15am.

We were met by Sid who herded us into the unheated Hut 12 with traditional 40 Watt bulbs - very much like the military we all thought.   After a few minutes instruction on how to use the Electronic Audio Wand we were free to explore the site which Churchill once described "As the Geese which laid the Golden Egg but never cackled".   A map plan was given out to everyone
All other buildings we visited were nice and warm!

Plan of Bletchley Park in 2010.

Much had been improved in the last few years - the entrance gate had shifted from by Hut 12 to a more central location and Hut 8 had been replaced with a nice new but identical hut which was Opened by Prince Charles.
It is essential to go at a weekend or Bank Holiday if you wish to see the Volunteer Huts open.

A number of persons headed for Hut 4 - the Cafe to enjoy a nice coffee or hot chocolate.   Others headed for the Mansion as we were told it would be shut for 2 hours as there was a Wedding taking place there.

Jean, Pauline (Organiser) and Jack outside the Mansion.

The Mansion has had a new roof and generally tidied up inside to give it the "Stately Home" feeling.

The Typex Cypher Machine used by the British during WWII and for quite a while after.
Photo by Colin, G0TRM

The Germans could crack the code for it but never quite realised the significance of it as it is thought they only could gain access to a trivial communications link.

It was poorly built and a pain to get running reliably.   Many of the interconnection points easily corroded with the acid from the Operators hands.

Its one great strength over the German Enigma Machine was that it produced a paper tape copy and this improved the overall use of it - it did not rely on someone's bad writing.

A 3 Rotor Enigma Cypher Machine used by the Germans during WWII and for quite a while after by a number of other countries.

Close up of the Keyboard and Patch Panel below.
The contact material was superior to that used on the British units.

A 4 Rotor Enigma Cypher Machine.
Adding another Rotor vastly decreased the odds of "cracking" the code.

As with all "substitution Cypher Machines" it had to change "a" into something else - it cannot keep the same letter. Bletchley Park used this fact to examine formal German messages which always used the same format like "Weather Forecast".

How the Rotors are wired.
Photo by Colin, G0TRM

How the Code was cracked by the Poles.
Photo by Colin, G0TRM

Close up of the display board which points out that without the "Y Service" there would have been no "Bletchley Park".

The "Y Service" employed Radio Amateurs to listen to German radio traffic and a motor cyclist took their messages and delivered them to Bletchley Park.
It is thought about three people copied each message and this was used to check for errors.   It would be pointless spending time on unscrambling rubbish!

Typical "Y Sevice" monitoring position.

Note the American manufactured HRO Receiver.   HRO standing for "Hell of a Rush Order" as told by the Production Manager to past CARS President Roy Martyr, G3PMX in the early 1970s while in a QSO with him.
Photo by Colin, G0TRM

A DST 100 monitoring set with part of a Marconi CR100 to the right.

Bank of AR88s.
Photo by Colin, G0TRM

One side of the rebuilt BOMBE.

The "inside wiring" of the rebuilt BOMBE.

The ALVIS Cypher Machine used from 1968 to 1984 by the British Military.

The ALVIS.

A Harrier Jump Jet.

Alan Turing - Mathematician - Codebreaker - Father of Computing, 1912-1954.
Photo taken by Murray, G6JYB.

Photo of early computers inside the National Computing Museum.

A Dragon and a PET.

A PDP11.

Description display for the DEC-PDP11.

Early wired programmable computer built and used for Harwell Atomic Research Centre.
Used all General Post Office items such as 3000 Type Relays but to a poorer specification than those used by the GPO.

A set of Disk Drives

Colossus - Designed and built by GPO Engineer Tommy Flowers.
World's first Programmable Computer.

Amateur Radio GB2RS Station.

The Amateur Radio Station with Alan, 2E0GLD nearest the camera.

RSGB New Hut - to be opened in April 2011.

A Kitchen from about the WWII era.

Photo of the Bride having her photo taken by the lake.

Entrance room to the newly rebuilt Hut 8 which was opened by Prince Charles.

Creed P45 Punch Tape machine .

Close up of a Creed Printer.
Photo by Colin, G0TRM

Marconi Undulator UG6.

Marconi Undulator - Receives incoming Morse Code and prints on a paper tape.
More modern than that above.
Photo by Colin, G0TRM

Another Undulator - really old - maybe 100 years old.
Photo by Colin, G0TRM

A typical GPO MCVF installation.
Post Office MCVF Installation.

Polish display area.

Diplomatic Wireless Service (DWS) Display run by Dave White.
Photo by Colin, G0TRM

DWS Display.

Colin, G0TRM hammering out a Morse message.

Minerva 499 SH special receiver for Siemens Hellschreiber
Photo by Colin, G0TRM

A typical Tape Station.

Receiver R1132 - VHF Receiver as used by the RAF during WWII and after.
Underneath is an Eddystone Receiver.

A Plessey PR1550 Receiver typical of the new generation Receiver early 1970s.
The later PR1553 had a Digital Display and they were easier to maintain than the Racal RA17 series.

DWS Display run by Dave White.
The following photos by Colin, G0TRM

DWS Display run by Dave White.
Photo by Colin, G0TRM

DWS Display - Pye Seafarer Model 1112.

A good selection of Morse Keys

Tape Training aid from the USA.

End of the tour of the DWS Hut 1.   Thanks to Dave White.

Stan's Coaches picking everyone up after a wonderful day at Bletchley Park.

Our thanks to everyone involved.