Voice and data encryption unit
- wanted item
The TSEC/KY-99A is an Advanced Narrowband Digital Voice Terminal (ANDVT),
developed by the US National Security Agency (NSA) in 1994.
It was used for many years by the US Department of Defence (DoD)
for secure voice and data communication over narrow band radio channels.
It is interoperable with the other members of the ANDVT-family and is
backwards compatible with the wideband KY-57 (VINSON),
which it replaces. It is also known as NSN 5810-01-391-0187.
The image on the right shows a typical KY-99 unit that was built by ITT Industries.
The unit measures 140 x 77 x 200 mm and weights approx. 2 kg.
It is a stand-alone unit that needs its own battery (connected at the back).
At the front are three sockets.
At the top are two standard 6-pin U-229 connectors
for AUDIO and DATA respectively.
The DATA connector is also used to connect a standard
key FILL device
such as the KYK-13.
The 13-pin high-density connector for the radio is at the bottom left.
The volume control/power switch is at the center.
The ANDVT-family was launched in the late-1970s
with the introduction of the AN/USC-43 Tactical Terminal (TACTERM).
It was based on the NRLs first successful implementation of the LPC-10
vododer in 1973
 and uses
SAVILLE as one of its algoritms.
The KY-99 (MINTERM) is in fact a miniaturized version of the TACTERM.
Its design is based on a modular architecure and, compared to TACTERM,
its size is much reduced.
The KY-99 features full key distribution plus remote key capability
(OTAR) and was certified for secure traffic up to TOP SECRET
(NSA Type 1).
Development of the KY-99 was started in the early 1990s, with the first
training sessions around 1992 . The design was finalized in 1994,
when it was assigned an NSN code.
It replaced the narrow-band KY-65 (2400 bps, HF)
and the wide-band KY-57 (16 kbps, VHF/UHF).
By 2006, over 40,000 ANDVT units were in operation at the US Navy, Air Force,
Army, Allied Forces and US government agencies.
This includes 9363 units that represented a value of US$ 6207 each .
The MODE selector is at the bottom right. There are 5 modes of operation:
Plaintext, Ciphertext, Re-key, Off-line and ZEROIZE. Pull the knob to
delete all crypto keys instantly.
The rest of the operation is via
the three push-buttons and the green 8-position alpha-numerical display.
- Single channel
- Narrowband, wideband or wireline
- Secure voice and data (simultaneously)
- Full key distribution
- Over-the-air rekeying (OTAR)
- VINSON (KY-57/58) legacy mode
- Improved SATCOM performance, improved synchronisation
- Improved LPC-10 voice coding algorithm (V58), 2400 baud
- CVSD voice coding, at 12 and 16 kbps (wideband)
The KY-99A is compatible with the other members of the ANDVT-family, such as the
KY-100 (AIRTERM). It is also backwards compatible with some legacy products,
such as the KY-57 (VINSON), in which case it uses wideband
CVSD modulation. As far as we currently know, the KY-99 is compatible with:
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© Crypto Museum. Last changed: Saturday, 30 May 2015 - 13:11 CET.