Anoraks Corner by Tony Sale
Some hints on how to break this Enigma?

Scenario 1.
Itercept date: 15th March 1935. The following 40 ecipherments of message keys have been extracted.

AGL KYO . QDD DPG . COT FBU . FXN NKF
CUH FTD . SFZ TWA . EHT JSU . ZJA ZZQ
XLV BGB . GLW PGJ . RSR EIL . IQP ANM
ALG KGS . UEN IOF . RDM EPI . DHH YSD
VNT GVU . MKK LEP . YPQ HJZ . XBB BQX
QMC DRT . GTX PFW . BSS UIN . KEU OOE
HZU RHE . OUS XTN . WYE WCC . JWQ QAZ
LAY CXV . PBI SQK . BRO UDR . BII ULK
NDJ MPY . RAB EXX . FTV NFB . COT FBU
TNC VVT . FXN NKF . JCF QMH . IJI AZK

One partial message is:

OKH VON JSW 15/03 13.25 JYK QCP
WCKVE KOFLB UVQKI IEOAY UFA.....

Hints:
The date of the intercepts implies a three rotor German Army/Air Force Enigma with six steckers.
The two groups of three cipher letters in each message header inplies the repetion of the encipherment of the message key, thus Marian Rejewski's "characteristics" can be used to find the Enigma configuration.
First construct the "characteristics" for this set of intercepts and use them to discover the Indicator.
If you don't know how to do this, go back to the Anoraks Index and read the page on vulnerabilities which leads to an example of using Rejewski's characteristics.

When you have done this on these intercepts, you will get out the Indicator for the day and also the six steckers.

In order to decrypt the partial message, you first need to decrypt the message key, then put this as the ring setting and do an exhastive search for wheel starts which decrypt the first three cipher letters as "ANX", the guessed message start. (Hint the left hand wheel start for this is J).

Now transpose the rings and starts using the formulae:
new ring = 2x(key-letter)-(start-just-found) With these new ring settings and the message key you should now be able to decrypt all the message fragment. If this works you have the complete Enigma settings, wheel order, rings and steckers.

You may need to print this then go look for tools.

This page was originally created by the late Tony Sale, the original curator of the Bletchley Park Museum,

Anoraks Corner by Tony Sale Some hints on how to break this Enigma?

Scenario 1.

Anoraks Corner by Tony Sale
Some hints on how to break this Enigma?