Mftn tnn1 

; ; l 

• . ........... ~O.~ .. :.l63tf ... :: .. . \ 

_!elecrypto Apparatus 

~_Qeneral 

'!:he telecrypto appar~:itus has been develop{~d in order. to 

er:sure secrecy in te lewri ting cou.u~u.nicut ions. In such cases 

the telewrit0rs will not be connected directly to the line 

but over the telecryptds as per figs. 1 and 2. . '• . 

The secn~CJ of the message.s trunsu:ii tted over the line 

i~3 obtained in suc:h a way thr.it every u.nd each of the impulse 

cowb1nutions, eo,itted .t"rom the tele·....,riter on depres.sing ~eys 

on its keyboard wiJ.l be .Dodified in the teler:ryrto, and will 

be transIJ.itted over the line in this m.odif'ied (ciph~red) fortil. 

At the recei vin.g end the ciphered i!'i..pulse .combination.s will 

be re-transforriied ·th.rough the action of the correspo.ndi:ng 

telecrypto apparatus and received by the telewriter in its 

original fora:,, so that both telewri ters wi 11 write the original 

text. '.\hen trull.srt,i tting a message the telewriters are used in 

the normal manner, as if no additional n:ppara.tus were connected. 

'lihc reo.ding of' the coL...n:.unications on the line by third parties· 

wi 11. hov:ever riot be possible, as the imrulse coilo"u i!rntions 

between both telccrypto apparatus are ciphered. 

B. 'l'elewriting sys~ 

1

1

he te lecrypto is constructed in such. a manner that it 

can be used for both 5-pulse and. ( ufter reconn.ect-ion.) . for the 

14-pulse system. 

1. •relewriting system acco:r-di.ng to the international 5-pulse:--

code. 'lhe dif'f'er;-mt signs are composed and transmitted by 

5~pulse combinations. 

eclassified and approved for release by NSA on 11-19-2014 pursuant to E.O. 

3526 

DR. ING. E~ GRETENER 

,. ' 
._ .. 

. ' 

·~-

,,.., .... , . 

~:t~ .. -~: ·. :· 

~}., •· .. 

REF IJ;?:A414B51.Y 

- .... - . 

Lua.in opera.ting systeir.s: closed circuit current 

_Doub le current 

n.Udio frequency tP.legrarhy 

1.tl:1.xiu1um operatiug speed: 7 signs per seco:u.d. 

2. ET_K.-telewriti~ syste;.u (Dr. E.Gretener h.-G. ). 

.'-:o. 163e. 

'I'he dii'feruut 3igns ure cor;;.r.osed and trunsmi t ted by 

14-pulse cor;.binations. The resr:,ect i ve signs are not 

prj.uted_, as f.i. v.ith the 5-pulse systeu., in one operc.:.tion, 

but crn1bined tro~ 14 differeat ele~entury signs. ~acb 

eleu.ent. corresronds to one of the 14 impulses. 

Gpera.ting s~:stem : 

Audio t•raqu.ency tole[7L:phy 

l<~tu.i11.um orerating sreed : 5 nigns rer second 

1,,avunta.ges: ..:.1. i.!iUCh simpler constr:;ction and $t.~J.llcr over:-... 11 

d illicnsions 1:;u1.d ·.~c igh.t t.tau ti!OBe of the 5 pulse syateu:.. 

Consider.:ibly s1iuller risks for f:J.ult;y trau.smission, 

especially for rudio cou11:i._u11ic:it io!ls. 

C. Operating rrinciple2. 

The telecryrto apparatus produces irur;ulse series of the 

same charactf1r us those of' the telewriting apparatus emyloyed, 

i.e. 5-pulse CO:!ibina.tions wheu used in conjunction ?.'i t.h tele-

"Wri,ters operating on the iutcruational systerr. and 14-pul.:>e 

corcbinati ons '\'ihen used v.'1 th ETK-api.~arntus. The cryrto-iru1 1ulseseries snd the impulse co~bination of the tele~riter ( clear 

text-impulses) will be co.•.Jbined, i.e. converted :in the w.unner 

hereinafter descriJJed so t.hat the cirher-i1£rulse S8rieB is 

obtained, r!nd this 11-ilpulse•series is then trannmi tted. 

·At the receiving eL.d these cir,:hered i~rnlse serie:.:> are 

::i.gain converted '71ith an ideutlcc~l cipl'lcr-impulse ecries aud 

tbe original clear text im.r:ulse series will be reconstituted. 

'!'he cryrto-im-pulscs materialize ever/ tit?'.e .o. key on tho telcwri ter is de1 .. ress.ed by the nt art im.rulae of the telf:·•·ri ter . 

~ti· l~~~~~~- :~1- ... · . ..... -. ___________ .., _________________ , ______ --1 

~ll-··',~"'.· .. -· A.Mc .... rliZlrlcb 620m 1000 llJ.<7 W1119 
•' 

.' -.. ~' 

REF ID:A41485J..Y 

- 3 - • 

The coniposi ti on of' the cr~-i.·tO-i..i:lfUL3e coa.bino.tions varies :i·roa; 

sign to sign o.:ud tne series of these vo.riations is to all 

practical puri:oses liu;i tless. If one f. i. o;tould ulv.ay3 stri.ke 

the key "12..", then the c iiihcred iwpulse co;cb inutious in tl:e line 

would change continuously. 

Fig. 3 illustrates as an ex~~ple the transmission of 

the letter "Y'', according to tlle 5-pulsc code. 1 - 5 are 

the five ele:;;enta.ry irtip'.llses, + ·•.L.en current and - no currer•t. 

Line 1 shows the iwrulse Co;.?.:biuo.tion, rroduced by the 

te le~ri ter, line 2 shov:::; a. crTrto iwp-11.se comb ina.t ion, in 

this e:xalilple the co1r.bination for the letter "L" • In the 

line 3 multiplied product of lines 1 t:.nd 2 is obtui:ued of the 

ele:L.eotary iliipulses. 'The convE:rsiou is done uccording to the 

f'ollov.ine; rule of a ll!Ul tiplic?it ion 

+ = + = 

= + + = 

It ·will be seen as a res·,;lt o-f the ciriher·ing orern.tion t~E·tt 

the letter "0" is obtained in this case. If the line L; 

tap11ed v:i th a telewri ter (without telecrypto), there 1;ill be 

obtained the letter ''0'' iusten.d of "Y '' • 

Frou. the lines 4 - 6 will be seer.:. thQ.t the origin.nl ~;igu 

coiLbinatior:L, as produced by the seHding te le':-:ri ter, \1,~i 11 be 

reconstituted by the multiplic~ition of the cii.hered imrulse 

co?"nbination v;i th the corresi--onding cr·;y-vto iwrulse con;binut ion. 

5-rulse systeu... 

As practically all the po ssi hle di fferr.nt L:i.r J lse 

cou.b inations in this syste!L Gto.1J.d for signs (letters, :.1.'..lll1er~ls, 

punctuation signs), the cir.hered ir; ... pulse co.Lt1binHtions Y:ill 

give readable signs du.ri ug trnnm.;issi.on. The uctiou of the 

telecrypto apparatus consists in tt.is case of the exc~:.3.r.ge o:f 

signs :. The letter 11 Y", f'or instu.nce, a3 written on the 

telewri ter, mu.y b~ exchuIJi~ed for arr "C" as a.11.own in the 

e.xa.i.r le above. A person, ?:ho ts.rs the line u.nd h~a no ~::.no?rledge of the crypto ifupulse series emrloyed, will thus oht~in 

letters and uumcrs.ls in an absolutely '.ll'bi trary sequence. 

A. Mc1ac•ll Z!iric~ 520 m 1000 Ill. 47 \1' 1111 
Mod. 1002 

14-pulse system· 

With the 14-pulse system ~b_out 16 ~000 ~uipulse combi"nations 

can be obtained; of these only about 50 combin~tions .(= 0,3%). 

·give read ab le signs. By the conversion. of' the c iear te"xt 

combinations_ 7li th those of' the_ crypto sc:ries, there will 

generally be obtained unreada.b le impulse combinati.ons in :the 

ciphered. impulse se.ries, so that ~n nxn may for instance be .. 

changed into IS etc. A telewri ter, branched on to the 

collimunication channel,· and not equipped with a. telecryvto. 

apparatus, will ·here write unreadable signs. 

D. The ciphering keys 

The keying elements of the ciphering key serve t;o obtain 

the vari~1b le crypto-impulse series. .As ~lellients". for ·the 

cirhering keys a number of wheels (f.1. 14) are .used~ These 

rin wheels carry a number of slidable or rotatable pins,which 

can be displaced individually, by hand, and can take two 

dif'ferent positions. In one of these positions one or several 

contucts will be closed (or opened), and vice versa in ·the 

other position. Each pin is definedby·a number on the 

circumference of' the pin whe~l (key m.i~ber). · Th~se lrny " 

numbers are also used to de:fine the starting positions of the 

pin wheels. An or er at ing mecha.ni.sm acts on. the pin ~vheels a.11d . . . -

moves them after each tra.nsa.:i tted sign, in an i:rregular- marine+. . . . ' 

The movement rhythms can be varied and can be cha.ri.ged · . 

arbitrarily by hand. 

The pin wheel .contacts. a.re corine.cted in accordance with ... 

a special system. The co~1nections term~na.te ·a~ a c_ollector,, 

wl;tich has f'ive sectors ~or the 5-pulse. ·system and 14 sectors. ' 

:for the 14-pulse ·system~ The individual seg?J1ents are_ eit~er 

electrically e.ctivfited, or not, dependfng on,. the position:of 

the pin whee ls. · ~IP.en a coll~ctor brush passes. all· segments~. 

a 5-pulse or 1.4-pulse combination, or· t.:b.e so· called. cril'lo''-_ . ,' . .• ;_· .. . , 

impulse series,· is. obtained. · 

An exceedingly c~mplica.ted "p:r~gram" fbr· ti.le. composit·i-~n 

of the crypto .impuls~ se:ries is obtained. on. ~.ccouht. oi'. tl;le . ' . . 

.. : -. 

' 

·.I 

•• • j • • i 

. . . -~ 

. , . '. . ,-1 

.. ·A..M~)i Zilrl~b- 520!"· tOOO. lll,47 Wlllll_~'.I, 
Mod. 1002 

REF ID;A41485~ 

- ' - .., No.16~e. . 

system used i'or the com1ection of the pin wheel contacts. 

If' f .i. the first impulse element gives "current" or not may 

depend on the !1osition of' up to 12 rin wheels, :3.nd their 

rosition at thut moment is derendant on the coir.tbinations used 

for the ruovement of' the :tin v:heels up to that UJ.oment • 

... ddi tional keying eler1 en ts a.re also used, in the form of 

ci11hering ( ~ erwutation ) collectors, of \'Jhich ·one is alttays 

sup11lied. This is adjustable by hand. On spec l.a.l derr:and 

one or two extra ciphering collectors, Vlfl.ich obtain the S:ill!e 

irregular kind of ILoveuien.t as the pin wheels, are also supr-lied. 

'l'he ciphering collectors are marked on their circumferences 

with numerals in order to define their starting positions. 

There are also supplied special connector plates, which can be 

exchanged in a very simple way. 

The pin wheels and the two ciphering collectors with 

automatic ~ovements PS 1 and i'3 2 (Fig. 4) are mounted on a 

shaft at the front end of the apparatus, while the hand 

opcrtited ci~hering collector ?S 3 is to be found at the right 

hand side of cover of the machine. 

E. Comrosing the ciph~rin5 key settings. 

We distinguish bet~een interior and exterior set~ings. 

The interior settings are changed ~ore or less frequently, 

derendi:ng on the intensity of the crypto service, while the 

exterior settings are coruposed when sti:irting a couimunication 

series, or eventually every time a telegrw.n is sent. 

The TKG 5/14 allows the :follov.ing key settings 

a) Interior key settings. 

1. The positioning ot' the pins OI! the· pin wheels, which 

total about 500. 

2. Arbitrary a.rrangetuent of .the movellient.program for the 

14 pin wheels and the two ciphering collectors. 

3. The choice of' different connection J)letes for the 

ciphering· collectors. 

'•.: 

; . ~ I 

_:\'. 

. ·.;;: ~~:~~ ---------------------------A.-M-._-r1""'1 -Zlr_leh_6_!0_m_l_OOO_OJ._•_'i1911 ·· fl'"Will~<::~~ •, :.Rr.-¥~ 
. .• .. 

REF ID:A414857.Q 

• - 6 -

No.163e 

b) Exterior key settings 

l. The sturting rositions of the 14 pin wheels at the 

beginning of' the cou>munication, !:..Dout 35 different 

positions .for euch r1in .,.;heel :J.re possible. 

2. 'Ihe sturting positions of the three ciphering 

collectors, each collector cu.n take 28 diff'eront 

positions. 

Both the interior and the exterior keys can be set by 

hand without any tools. 

To set the· pin wheel pins, as ..,,ell as the stu.rting 

positions of the pin v1heels, a. r le.xiglasn cover is opened 

with the aid of the. lever .,H", when a sufficiently large 

sector of each pin wheel will be uncovered. 

In order to compose the movement program for the pin 

wheels and ciphering collectors, the protective cover "A" 

is opened. The changes can be lliade by v~rying the position 

of contact plugs. 

It should be noted that t.he different key eleruents can 

be adapted within reasonable lirri.i ts to the needs of the 

customers, with regard both to constn'!.Ction and wiring 

diagrams. 

The construction of the '£KG 5/14 app::J.r1..i.tus offers an 

exceptionally high degree of safety, when fully e(iuipped. 

In many co.ses the equip~ent can be simplified; the wishes 

of the customer can be taken into account. 

The teleOr}"Pto will be built in such a l.'aY that the S.ille 

appa.r1ltus can be used together with tele·:.riters according to 

the 5-pulse .2!. the 14-pulse system. The change-over t"'rom 

one systelL to the other is done by cil.anging the position of 

a. connecting plug "Utt, after rer:...oving the cover plate "!>" 

(Fig. 4)_, and by the exchanging of two gear wheels. 

The telecrypto apparatus will be built for 

1. 5-pulse closed circuit current · ~ 

i4-pulse E'rT ~ or 

'.;{~:;::~:':··>.. I.~ .. ' : .. MIQ2' "·~· .... ----!----------...:..-------------.-.--li...,H _______ J 

,.,:. ,..·,: ·.f:> . , , '. : , • _, rlob 520 m 1000 UI. '7 W Ult 
Mod. 1002 

REF ID:A41485 

- 7 • 

No.163e. 

2. 5-pulse double current l 14-pulse ETT or 

3. 5-pulse ETT 

14-pulse ETT l according to the wishes of 

the customer. 

Wire or radio can be used as cowmunication channels. In case 

of radio the swaller sensitivity of the 14-pulse system 

against perturbntious should be noted. 

F. Electrical dater. 

The telecrypto apparatus c:Jn be used v.i th : 

1. 110, 125, 145, 220 and 250 volts alternating current, 

50 cycles 

Po\'1er conswr;.ption abt. 100 VA. 

2. 12 volt direct current (Battery) 

Power consumption abt. 70 Watts. 

G. ~echunical construction, dimensions a.nd weigr .. t. 

The telecryi;to apparz1tus cons.ists, as will be seen. on 

Fig. 4, of a f'rame of sheet metal UT, which contains the 

electrical elements such as vacuWL tubes, transformer, 

resistances,, condensers etc. e.nd of an upper part OT, v.'hich 

contains the mechanical elements motor,, gears. ciph~ring 

collectors, pin wheels etc. The upper part is hinged on the 

base# and by tilting it up, all po.rts in the interior of 

the base will be easily accessible. 

A carrying case is provided for the transportt"l.tion of 

the apparatus. 

The.di~ensions of the TKG 5/14 will be seen onf Fig. 4. 

They are 

Width 

410 mm 

Depth 

350 mm 

The weight is about 55 .lbs.(25 kg.) 

Height 

225 mm 

..... 

. .. 

A. 11-u Zftrlob 5i0 m 1088 ~ °" _,.. JJ:lf ' . , ·.'"-'• •. :,;..r._'-' ... _ 
REF ID:A41485].R No.163e 

- 8 - • 

H. Qriera.tion. 

A:f'ter having connected t:ae telecr:yvto to the u:ains, 

or to a. battery, and to the tele\.ri ter, service coILruunicution is first established in clear text. ~he lamp L1 

indicates that the ai:;paratus iB connected. 'l'he S\ti tel:. d 

is set in the position "clear" which disconnects the 

ciphering mechlinism of the t~lecrypto.· In this position u. 

red lamp L2 warns that clear text is being sent. A~er 

having sent the routine wessages, and af'ter huving Ui.ade all 

key settings, the switch is c~-ianged over to 11Cry11to", 

after which the secret communications can start. 

W.hen the trausniission conditions are poor,· f.i. 

atmospheric disturbances when using radio channels, it may 

ho..r.fen thut the t'Ilo telecry1'to appa1·atus fall out of step. . . F'rom this moment the deciphering a.t the recei vi11g end will 

become faulty, so that the receiving telewriter will not 

write clear text any longer. 

The orcrntor at the receiving end will in this case 

strike the special key of his telewriter, which interrupts 

the tr·unsmission. Both operators then put their switchen 

S in the "clear" position. In order to avoid the tedium 

of making new settings of the secret keys, a counter "L:." 

is provided for, which autoraatically counts the nW!lber of' 

operations of the telecryptos. In order to put the two 

telecry-ptos into step ugain, the operator of that station, 

whose telecrypto got behindhand, hn.s only to press the 

button D.a number of times, until his counter shows the 

sru.ue nwober as his correspondents. When this is obto.ined, 

the switch Sis put back into position "Crypto", and.the 

transmission of the secret ruessage can be continued. 

A. H04"Crll Zlrlch Sill m 1000 lll. 47 W 1119 
Mod. 1002 

FS 

TC 

y 

L 

0 

0 

L 

y 

Telewri ter e 

Telecrypto 

FS ~ 

Impulse combinations 

of clear text 

- 9 -

Line 

- -

Fig. 1 

No.16~ 

Impulse combinations 

of clear text 

FS TC 

Radio communication 

.---r--- - - - - ---z._ 

Ciphered impuls TC FS 

Impulse combinations 

of clear text 

1 2 3 

+ + 

+ 

1-- --- -- -

+ 

I 

I 

i 

I 

4 

+ 

+ 

.. - ---- --

+ 

+ + 

I 

I 

I 

combinations 

Impulse combinations 

of clear text 

Fig. 2 

5 

+ Impulse combination of the tele- - . - ~ writer 

+ Ciphering combination of the 

transmitting telecrypto apparatus 

+ Ciphered pulse combination 

(transmitting side) 

Transmitting Channel 

+ Ciphered pulse combination 

(receiving side) 

Ciphering combination of the 

+ receiving telecrypto apparatus 

Clear pulse combination on the 

+ . receiving side. 

Fi~. 3 

J.. llln..,rll Z6rillil 620 m 1000 UJ. 47 W 11111 
A 

Bt 

H 

rs i 

PS 2 

PS 3 

s 

L l 

L 2 

z 

D 

u 

p 

OT 

UT 

No,163. 

OT PS3 

,,. Klar 

R ~ K ypto \ 

I ~41Q__~-··----~ -~ 

= 

= 

= 

= 

Pin r;heels 

Lever 

.S 

Fig.4 

Ciphering collector II II 

L 

auto~atic~lly driven n " 

= Ciphering collector driven by hand 

= Switch 

= Red lau.p 

= Green lump 

= Counter 

= Button of correction key 

= Connecting rlug 5-pulse to 14-pulse system 

= Cover 1:l::ite for the elerr:ents to change the 

ruovernent program of the .rin \':heels. 

= Upper part 

::: Belm•er part.