Installation Instructions

OM-E 2072-09287-00
3-58
3-13. USING THE VOCODER
3-13.1 Introduction
The Micom can be ordered for with the vocoder option. The vocoder provides voice privacy at good
voice quality, using digital signal processing techniques.
The vocoder supports the following protection modes:
• Privacy (PVT) mode. The vocoder can store up to 8 private keys for use in this mode.
• Digital (DGTL) encryption mode.
You can select the desired protection mode, or switch to the clear (CLR) mode. To support protected
communication, the radio bandwidth is automatically switched to 3.3K.
The vocoder can be used in all the modes (Channel, Frequency and ALE).
NOTE
When using the DGTL mode with ALE, the radio scans in the Clear
mode. When a vocoder call is detected, the radio automatically
switches to the protected DGTL mode after the link is established, and
returns to scan in the Clear mode after the link is disconnected.
3-13.2 Using the Vocoder
When operating the radio with the vocoder in the Channel, Frequency or ALE mode, you can choose
between the CLR, DGTL, and PVT (private) modes:
• PVT activates the automatic voice privacy functions
• DGTL activates the vocoder digital encryption function
• CLR reverts to regular radio activity.
NOTES
There are eight preprogrammed PVT keys, PVT1 to PVT8, and one
digital encryption key (DGTL). Program the key to be used as
described in the Programming the Vocoder section starting on page
3-59. The currently-used key number appears on the screen.
In the PVT and DGTL modes, the vocoder controls whether you hear
or not the received signals, and therefore the squelch option (SQ (F3))
is not displayed. The Squelch option (F3) appears only in the Clear
(CLR) mode.
When the PTT is activated, a hold-off tone sounds. Wait for the
hold-off tone to end before talking.
To use the vocoder in the Channel mode:
1. Press the F1 key whenever it is necessary to toggle between the PVT
(Private), DGTL, and CLR (Clear) modes.
CLR
BAND
SQ
DSP
CH 6
F 16,000.00
USB
I
BW3.3K