|
|
|
|
|
|
|
← Telsey Voice
Time domain voice scrambler
The TS-500 was a rather simple mobile voice encryption unit, developed in
1976 by Telsy in Italy. It is the first in a range of
secure voice products that were released after the company started in 1971.
It uses time domain voice scrambling and is also known as the OEM variant
Teltron SP-810.
|
The image on the right shows the front panel of a typical TS-500 unit.
It only has one switch, that is used to select between clear and encrypted
voice. No other controls are present.
The cryptographic key is no more than a small PCB with a labyrinth
of tracks that is inserted into a slot at the front of the unit.
In the image, the key-card has been extracted from its slot.
The card is symmetric (i.e. it can be inserted upside down) and is extremely
easy to copy. Furthermore, it allows only a limited number of combinations
to be made.
|
|
|
Despite the simplicity of the key card, the actual electronics
are rather advanced considering the unit's age.
The TS-500 contains two PCBs that are easily revealed by removing the
cover. They are mounted back-to-back, so that the components are
immediately visible. The Logic Board
contains all digital components, whilst the
Audio Board contains the analog components.
At the heart of the system are two FX-209
Adaptive Delta Modulation chips,
manufactured by CML in the UK. One is used as an encoder and the other one
is the decoder. Analog speech is digitized with a delta demodulator,
after which it is scrambled in the time domain and converted back into
an analogue signal by means of a delta modulator.
The TS-500 was succeeded in 1978 by the TDS-2000
series duplex voice encryption devices that offered 2-dimensional
scrambling.
|
|
|
|
Any links shown in red are currently unavailable.
If you like the information on this website, why not make a donation?
© Crypto Museum. Created: Friday 14 September 2012. Last changed: Saturday, 24 February 2018 - 21:16 CET.
|
 |
|
|
|
