Homepage
Crypto
Index
Glossary
Enigma
Hagelin
Fialka
Nema
Voice
Hand
OTP
EMU
Mixers
Phones
FILL
Codebooks
Algorithms
USA
USSR
UK
Germany
Yugoslavia
Ascom
AT&T
Bosch
Datotek
Gretag
HELL
ITT
Motorola
Mils
OMI
Philips
Racal
Siemens
STK
Tadiran
Telsy
Teltron
Transvertex
TST
Spy radio
Burst encoders
Intercept
Covert
Radio
PC
Telex
Telephones
People
Agencies
Manufacturers
• • • Donate • • •
Kits
Shop
News
Events
Wanted
Contact
About
Links
   Click for homepage
Crypto phones
Secure telephone equipment

Secure telephones are telephones that provide some level of voice security, in order to protect the calling parties from eavesdropping. Crypto phones are a special type of secure telephones that use advanced digital techniques for the encryption of voice data. Depending on the type and level of encryption used, crypto phones may be restricted or classified items.

Computer algorithms for government and military use, are generally controlled by the National Security Agency (NSA) in the US. They are divided into several security levels, of which Type 1 represents the highest level of security. Such devices can safely be used for top secret messages.

Secure telephones on this website
SIGSALY secure telephony system (Ciphony I) British WWII scrambler phone KY-3 wideband secure voice system with KYX-9 desk set Secure Telehone Unit STU-I (KY-70) Secure Telehone Unit (ITT, Northern Telecom) Motorola STU-II/B SECTEL (NATO-version) Secure Telehone Unit (Motorola, AT&T, RCA, etc.) Secure Terminal Equipment
STE
Motorola SECTEL range of secure telephones AT&T/Lucent 1100 STU-III secure phone (later sold by General Dynamics) CVAS III Secure Telephone KY-68 Digital Secure Telephone Philips Spendex-40 secure telephone for voice, fax and computer Philips Spendex-50, military secure crypto phone (a.k.a. DBT) Philips PNVX secure crypto telephone Racal MA-44741 Secure Phone Adapter
AT&T TSD-3600 Telephone Encryptor AT&T/Lucent 4100 crypto phone (later sold by General Dynamics) The Siemens DSM Voice telephone encryptor Siemens Crypset 100 crypto phone Hagelin (Crypto AG) HC-3300 crypto phone Hagelin HC-4220 Fax Encryptor Hagelin HC-2203 PSTN Phone Encryptor Mieco 25A telephone scrambler
Telsy TDS-2003 portable voice encryptor Telsy TDS-2004 telephone voice encryptor Telsy Cryptophone 7000 Terma ET-10, Digital Tactical Terminal with secure voice and data capability Siemens CTE-020 Remote Digital Engineering Order-Wire Terminal Tele Security Timmann, TST-7700 Voice and data encryption system Gretacoder 101, speech scrambler Mobile frequency and time domain voice scrambler
Elcrovox 1-4D narrow band voice and data terminal (STU-II compatible) Rohde & Schwarz Elcrodat 6-2 Not truely a crypto phone, but usable on crypto-enabled telephone exchanges
KWF
Voice scramblers
Older types of secure telephones generally use a technique called frequency inversion. They are sometimes called scramblers and are inherently insecure. An example of such a scrambler phone is the Mieco 25A (shown above). Even voice scramblers that use time-division speech scrambling should be considered insecure by today's standards, even when the two techniques are combined.

 More about scramblers


Further information
Any links shown in red are currently unavailable. If you like the information on this website, why not make a donation?
Crypto Museum. Created: Wednesday 07 December 2011. Last changed: Thursday, 09 November 2017 - 05:19 CET.
Click for homepage