, . ~ 

• 

REF ID:A67432 

S.• 1'be •DePd.. 8CCVllC1 an4 c!'7!'1tognt1h1c Mlr"...rlty ot moh a il•!oe 

•111 cel"ta1DJ,j be tar l'ftAter than t.bl!.\ of the ";>neent Ji.Ti•ion .11e14 

Coc!.e. '•J!l o& 'Jn• 

lea" 

meet.11MI: 

• .,, 11p tor 

the 

tbis 

rer

devi~e. 

u·e~t• 

(_(~. 

''PA!""'~ 

'). u>oA 

1 

~C. 

of •A1U.ta17 

·~) 

~ 

;}. !ha ~erd. - t. t~'Tl...rrttar ka:pf)oal"d. c-mitr-oill~ a b.ank of 26 

elacle-1'019. darable-th!uw' svt.tchea cont"l"Ols the -aaal'tine. '!'he bQ'boeri 

i• :namaa.117 trpel':lted 1:t the ull'U\l ~. The a~t ot the 'a!ys 

eorresoond.s to im.t of \he atand.u"cl 9Tboard bt1t the D1S M7 be maller. 

closer t0A9ther, 'lDcl opos-ate direc'l.7 do~ on the cont-ct l•en, u 

ta the ~!Piil cr,,i:t.~1'.!.c cle91ce NC811tl7 t"onrvded to the Sit?&al Con. 

tai>orllt.oriol!s at Ion uomto. 

3. 'ti» ncordtng mcbaniam. - A- the •st lzmor&Allt recr~Srement• tn 

tnta comsec&1on ue tiba' the record!~ Of!Chen111?3 be llDl!.l.19 n11gged 1n ecmnr.x:tloa, and. 01)er11ie cm •Hr./ little oower. !hare la nothing oa the arlmt. or in cam-a of dnelooeklnt wb1ch now •"''• theae remi1Te111enta smd. 

nch a mecban1a •Ill m_.,.. to be 4nelo1:Mld tor tbe 'l'!"lll'Oowe. 

£• 1' la nco....-ncled. tMt camerc1Rl org.NJlsaUo:na U::lllad. lD tba 

acmat.1"'1.CHOD at •niewrt,1la!!:. cala\11.at:lng, llDd a;;1.di:ac .ah!M• '8 coat.acted. 

la npn1 t:o thl• ~ at tit.. pro.jec,. 

£• A rwo1Y1Dc •ne wheel .... to offer beat noa•l'bSll"ll•. !ht.a 

•G'lltl pnbabl.T re.it la tcae-noonUDc rath•a- tha 1'Me-pda'111g. 

4. other tea.tvn. - • 919 wet.ch' of •&ln NObtm aacM mt to 

ueM4 15 'PG'lncla. 1Da1114lng aan,.tnc we. 

l• ,.. .. ft!l\llJllllllld;•• - fttr anclpberbc amt d..clplteriag olrcnit• 4i YDl&• (a.I") will mttlce. ibr eatrolltac ...-••or :nlap a.aeocla'414 

trltb &he olpbeJloolrheel dlaplcw• mecllaaS-. a -11 _, o~ el.Via ,.... 

•lll 'be ftfl'llred (ab•t 4t ...,1,a). l'oftr retralnd. tor aoha.13' d.l111tlfllelllg U. 

alp'bar-Ueel• Md tbt catnl ""9.!1•• 8'14 tor operdlag tile neore.1ac •• 

me1-Dba ean 'be npa.1194 '1' a 1lalll lner or • a clooll-.,rlag us.w. or a 

" "" -~- I ,-"':, 

....... ~ ,;s 
-------------------- - -

REF ID:A67432 

cominatlon of lto&h. 1' l• reoomenw. tht.t ma attempt be macle '° dHlgn 

the ~arat.11• IO as to .a :1' aoasible t.o nerde the t1LUN macbal• 

'~ a eonblaa,lon of two 01' three d.17 c .. 11. (!A-9) amt a band or toot-operat.ed l••I'· 

Of't1ae of tbit Chief 3t 'Dal O:f'ticn.r, 

1t',•h!n4to119 '· e. 

~ 

___ .,. -.a.:--v 

IUllam r. 11'1edmu. 
• 

' 

.£• '?he anttAd. ~t·U!'qe.7 and cr~-:>to,gr.tr.h:lc •1JC'1ri ty or l(TlCt· a device 

will cert11inl.¥ be f;,;,r ~rentHr th.tm thrtt of the r>re9Mlt Jlvhion tield 

Code, tl'1'ta mePt1~ t'.he r~~ire·;:fluta "1f P::ir->"P.~'l'.lh 1 of !l~!ilitP-r;t CMl'aater1 atica" ""'t uri for thh d·~irfoe. 

~ £he k.e;ybol\J'd. - ,\ t~ry:u~"f1r1t.,r l-eyboP.r<i. eontr~ll iJIJ?: !l b.'\Jl'!.:'. of z~, 

aingle-r,ol~. d1,711bl ... thrQw 8\'fitc~"llJ Cl'.>ntrols thP r>1"1Cl·ine. 1'be keybo1;.rd 

iB :"nnally opor0 ted in the nRn.d !lA?Ul~r. 1'he ~rr,..n,p;er,.ent ot tl!O kr.f• 

corresponds to tb:-;t of t!:~ ahru:h.rd Jtqbo,:.rd lmt the lce79 fMY be smaller, 

clos11Jr togeth,,,r. f!tld Ot>~rAt• d1-recUy downwArd on tM conhot l~Yen, a• 

1a the ~i~ eryPtO.Sf"fll'l"ic device recent17 f'o'f'W~rd.e(l to the 'Si.null Corns 

Labou~t;ori~,, At tort Momr:mth. 

3. The recording mech1U11a:rt. - A· '?hfl H<Ost ir.JP<>rtnnt rec11111rmoente in 

t1 ie conn~ction ,..re thi-~t thFt record!~ i:tP.ChMht; be wna.11, rngf;ed in constri1etion, rind 0'1'4'rl\te on v,,..ry 11Ule r-o:..,er. rhfl!re ia notning on the nr"~ 

ket or in ecwnrae o'f dnelo~nt which no• Dl!"••ta t}'-,qso t"elJ'1it"em<·.nts "lld 

ancti l'1 mechRd9?!1 will h~,ve to he develot>~ for tbft ~lrro11e. 

J?.. lt is reco· rJ9nd.er~ th- t COM!'M~rehu or~"r•ht\tiona a'ld.llllti in tt.e 

constr.nction of t;ynewrtti~. erlcnl:<>ting, r.nd n, ... ding mr;.c:hin·;-a be cont:i;ct.ecl 

in rAg~rd tu this ··hua of tne rro.}~t • 

.£• A. :reYulYing tyr.e wMel sef'!:!a to. offer best •·ossll::ilit iro;!s. i'!~ie 

..,.0'1,ld probP.bly rf~m.lt 1n t:ipe-reoorditv. ra.th"!' thsn """":-e-printinr,. 

4. Other fe;·~~1ros. - A• 1'he weight ot ~l1tire rn.~chine on{~}it not to 

excefJd lb pounu"'• incltldinR c{;rryi.~ c:--.ee. 

:g_. 1 o-11?r rw:uirei":l'~nh. - lt'or eneiphP,rin.e; ~!W.2. deciphPrin;t clrcnita 

4~ volts (:Bt-9) •ill m1ffice. :<'or contro:i. l ir~ u.i:v'1ll'lte or r'-'l~YB ~.3~oci··t.ed. 

dt!J the eipbeJ\-wheel dis,.,lr..-ee: lent 1'W:haniem, a amtrtll M1Cmnt of electric po..vfil' 

will be req111red (nb-m.t 4· volts). ~~r reqnired. for ~\i1~ll7 dt~l--ei~ the 

cfrhcr-wheals nnd the control 11hecls. l!D.d for opert=1ting the reconU.ng 

meotiri1119Jll cr.:n be an-p.....,lif'd. 'b;! n h1md lev~r or by 11 clock-sorin~ dr1Te .. or n 
, 

r 

REF· ID:A67~· 

combinnt ion of both. It b reconllV!nded th; t an p.,tteropt be made to d~dgn 

the &!rar~,t11s so ,!',S to mtlke lt -~~sibla to O"Cerate the entire r1ec:hanbe 

by a cormin~tion ot two or three drr cells (P.,.~-9) and a band or toot-oper~ted 

lever. 

Of:f'ice of tbe c:def si~nal ·Offictir,, 

.~·.fil'hil1~ton, ). C. 

william F. 'Friedman. 
REF ID:A674ifD ....... 

1. !he. ba•io cr;yptograjlhio pr1no1pl~ ot thti aacshifte. - J!.• Us• 

rotatabl• co.ute\ora (cipher wb•elt) arranged aooordinr to •oh•• 

-outlined in litra. l. &nd 2 o! e.QCO!lpsts,1ng dratt •peC1t1CAUon1 (blolotu'i'e 1) co•erlng Joint 1ment.t.o. ot Jraak 8, f•l•tt, •Dd the uftder•i&ned. 

lave ttff :t.ntercbang•ble OOU1.\tato:r1, tbr•• o.t which Mn• as 11Ubst.ttu ... t1on oomautators, two •• 4ont~ol commutator•• 

.2• 'l'he two control co&-.utator• act1ni upon the three aubatitution 

CO&'IU'tatora will 71eld an enc1phei-1nr, ktty of oon1idenble l•ngth, ftl")'inf 

b4ltween a low"•r llal.t or 17,576 and en uppex- l1a1t: of ~lao•t l~,000,000 

charnoterm. (The exact length la a f"UDoti~n of ~ nuaber or variable 

faotora.) For •Oh tllfterent arr~ni ... l'lt ·of comutotors UPon the shatt 

the.re will ~ a ditterent kt.t7 of ltinrtr'> intU.c1.1.ted above • 

.1• '.l'he 1pHd, e.cc~a, and orr;tosrtt)hic aecur1t3 or such -A devic• 

will oerlllblly be equal to thst ot the pre••nt lliv1t1on 1'.el't Cade, llnd 

~>robabl.7 'be mu.eta 1*tter, t.hu• ••tinr th• req,u1~•ent• of Par. 1 or 

•utlitary li'hta"a.cteriftiaa" set up tor thia devic• in 11t;aor1tndu:1 of 

Se'1taber 10, l9J'• (Enclosure·2) · 

2. Th• k4117bau-d., - A typtwrita:r k91bc>lll"d cont:roll1ng a bank oL 26 

atnal .... Pol•, dolibl~tbrow n1tab•a contrql# the ll!UlOhintt. !he ktJ7boBrd 

ie •aJlUG.ll.7 QPerated in the usu.til anner. t44' &ri-Aflieaent or the t~7a 

corre1po11ds to th~.t ot the 4tnndurd ~qboard but the kl'J• &+\1 ~ MBller, 

oloaer to: •th•rt a.net c~rat• d1reotl,- donward c.\n the cont~ct lH'ers, aa 

in th~ tn4...a aaebine. 

3. The reco:rdinr, ••chfltt1•, - A• th• aoat iaportant require11.at1 1n 

thi:J couneotton ue th6.t, the r•cordine UCh!inift be ....i.1, ru,tged in 

oonatruct1on, ~nid otJer&te. on -Yery little bJOW•r• 1her• io :not.hin.e on the 

earket. or in oour•• ot Oe-v'elo~nt wh1ob now ... i,. th•ae r-au1reaent1 and 

auab • ••ohan1911 will ha•• to btl deYelo~d tor the purrX)••• SeYenl trP•• 

are 'br1etl.1' outlined in the aoooiapa.uying enclo1ure 3, 

ll• lfb1oh of th• echea•• 8hc;wn 1n lncloeure 3 will be aoat pracU.aablo 

tor dn•loi•ent lhould be d.•tw•ill•d after conference with SigMl Corpe Labore.tort"• or with per•onnel «tkllled in recordlne mMlban1aa, 

I.- other !Mtur.ee, .. !.• The •eit;ht of •nt1ro aaoh1nei ought not to 

••04t•4 15 pound.a, iticludtng CArrying CA••• 

• 

l!• .Powel" requirnonts. - Foi- cncipbv1ng- itna decipher1nr circuit• 4* Yolt1 (Nt-9) will tutf'ice. For controlling agn•t• 8a1ocuted with 

th& ci!>her •h••l• and th" aeohaniRa, a :!all uount of el•ctrio power wUl be 1'ei{\llred · (about 4j TOlt1) but 1101t. or 9ower required tor act.u11ll1 

perto.raing tbeae !unctions can be BUP.vli•d b7 2l huid l~ver oi- by a cloekspr1ng dr1ve, or a ca.b1nea.t1on or both. lt •111 p.robably be ;>oesibl• to 
f 

\ • REF .ID : A67 4ji 

....,. 

operate tho entire ascb&ait• b,y a coabiiaatlon or tw~ or thrt• dr:., 

c.ile (BA.-9) and n, hand or toot operated la••~~ or it may be necessary to have a storage battery. 

Ottic• ot the Ghitt ~irn~l otttct~, 

'lf:lthington. n. c., 

Octobel" 4, 1935.