понедельник, 15 февраля 2010 г.

Scramblers: Harris AVS, Analog Voice Security

Harris AVS
Analog Voice Security

Author: SergUA6
Band Width ~2700 Hz
Low Range 300 Hz, in this example ~240-260, shift is possible
Count of Carriers 24 subchannels 112-113 Hz
Step between carriers ~112-113 Hz between centres of subchanneles
RX mode SSB

Sonograms:
pic.1 Generall view

The analogue not synchronizable scrambler, speech spectrum with band in 2700 Hz. It is broken into 24 subchannels in width approximately 112-113 Hz, these subchannels are replaced and partially inverted, time shifts are not used in this scrambler. The subchannels ocated densely without protective intervals as for example at 04XK100. Probably time shifts aren't used because of use on SW, though Codan them uses. This isn't direct inversion.