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This is a transcript of a super-enciphered message sent from Washington to Tokyo on November 10 1941.
The ‘plain text’ of this message consists of a two letter Japanese code designated ‘CA’.
The PURPLE machine settings used to encipher this message is 22‐7,3,10‐312.
It is possible to find the sixes and twenties alphabets with a hill climb using the Index of Coincidence as a detector.
The limited number of two letter codes and frequent repeats of codes gives an uneven distribution to the decrypt.

The source of the original document is:
NARA. RG457 NSA Historical Cryptographic Collection. Diplomatic Messages From/To Tokyo. NR. 1802, Box 733.

YMBKM LBERJ GFMUW ZHCCP JOZPV DYZMJ WBRDU ZGGWS
QHGEI BZHTK EQCAW THRWT KNFPH IQRSX HXHXI HIIQC XVVFL LJXQK
JSHKX MMBPG IJFUD VXBLO QIUOY INUDB RQPTR ISDTU TTAER YACXL
AWXZQ YMZTX RMBDJ KAOGJ ATFVE XQXLQ JWRGP IUWPC QNRXA GFOZN
TUYHI KOZOH MMYFJ EFBBM KXTFK ZFXHX ESJQK LOIXD
OLOEO IVXAA QTVZK IOMKR EOPEO LQLWR NGDQP SYMME QRNDE YYDRD
BCCNU ENDVU VXVDB HPXUW LDSJQ XUEFV SUAWP FUWSF SWXRQ WXGNN
QBBOH ZSCOP RAVAP AUKVV OXIGQ PGAQA KHQGQ VUQXC BKYQX EPJTU
QGOEN QGTVI MODFO RVKQE KRAGE OTREW SKRRA OICTA HTZHZ AAXHL
XVRWE TEGVT DQTLM YICSM UMZHG RXBTH VAKOU QOBTN LQMEQ JXRDD
OADDS BHRSS TZWZV HXMCD ISRQQ JVMHI PEHYU TCWPF QMTSU QSPGH
WMSDE VSCJS QSHSX XXPWB ATHTA MIHID SUVWH