Messages decryption

A complete example

Introduction

When the machine room has broken a key, the decoding room (DR) uses transformed Type-X cipher machines to emulate the Enigma to decrypt the messages and then forwards the result to Hut 3.

The Type-X cipher machine prints the result of the operation (encryption or decryption) as a series of groups of five letters.

Example

1) Here some cryptograms:

ZER/1. 6QG APY 1475 Kcs 1200 31 =ROM= =LNS= 
QKNVT WCGLV EUTCF ZTQSA WJCSR FQOOZ Z

ZER/2. APY N7Y 1475 Kcs 1630 245 =BER= =VEU=
FVNVT HWHVO VRWGM UBOPE PNOME PJNST CTAMT FGFGC ZDBGD XLUDH 
UADKC AWYXJ TGIXI ZAWRX DYCXR JKXAW EQPXN IVZXS YQMWK QSVPB 
UKMEP GKGHL BNZBC CVBQZ AWJFE ZQKWT HSDGZ LQDJD XYQCJ UTBTE 
EOJBT ZRLIU LTKXA AWTYT KVYHO SEKWU ZHYSO QOEFN TLISM VMAJS 
OYYXE CPGNJ QJGGJ YDBPP HTFZO ZTXML MCSEC ZSZPX NIKDQ

2) Here is the key:

• Walzenlage: IV-I-III
• Ringstellung: PNC
• Steckers: EH, AC, OJ, SZ, TY, IV, UX, NW, MR, FL
• Kenngruppen: mek ayn udm nvt

3) Here are the plain texts

ZER/1. 6QG APY 1475 Kcs 1200 31 =ROM= =LNS= 
Message key: DAK
Kengruppe: QKNVT 
Plain text:

KEINE BESON DEREN VORKO MMISS E


ZER/2. APY N7Y 1475 Kcs 1630 245 =BER= =VEU=
Message Key: LIN
Kengruppe: FVNVT
Plain text:

NACHR ICHTE NFUEH RERVO RLEGE NXWEG ENVER RATDE RTAKT ISCHE

MGLIE DERUN GENDU ERFEN AUFKE INEMF UNKNE TZBEI UNWIC HTIGE

MVERK EHRAL LEFUN KSTEL LENGE RUFEN WERDE NXNUR BEIWI CHTIG

ENFUN KSPRU ECHEN ISTQU ITTUN GZUVE RLANG ENXBE SATZU NGALL

ERFUN KSTEL LENIS TZUBE LEHRE NXNAF UEYBE RLINX