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Conventional Aegis or encrypted channels require Channel Guard on the channel
to operate correctly.
15.2.2 Clear Modes
Aegis clear and ProVoice clear modes are identical voice modes in which the radio transmits and
receives only clear (analog) voice signals. These analog signals are non-digitized and non-
encrypted. Clear mode transmissions can easily be monitored by unauthorized persons. Groups or
channels programmed for clear operation cannot transmit or receive unencrypted digital or private
messages.
15.2.3 Aegis/ProVoice Digital Mode
Aegis/ProVoice digital mode allows the radio to transmit and receive digitized voice signals.
These digital signals provide improved weak signal performance and they cannot be easily
monitored with a standard receiver. Groups and channels programmed for Aegis or ProVoice
digital operation transmit only digital signals. Private calls cannot be received or transmitted when
the radio is in the Aegis or ProVoice digital mode because the radio does not know the
cryptographic key used.
Message trunked group calls and individual calls will be answered back in the mode they were
received, assuming the call or hang time is still active. Individual, phone, all and emergency calls
will be transmitted clear if digital mode is disabled or inoperative.
• If receiving an analog message trunked call, the radio will respond in analog mode during the
hang time on the working channel.
• If receiving an analog I-Call, the radio will respond in analog mode during the hang time.
• When using the "WHC" feature to respond to an I-Call (after the hang time has expired), the
call will be transmitted in the mode defined by the system mode as programmed for the
current system if the ID being called is not in the I-Call list. If the ID is in the I-Call list, then
the call will be transmitted as defined by the I-Call mode programmed in the list for that ID.
DTMF
The overdial and hot keypad features for transmitting DTMF tones are not available while in the
Aegis Digital Mode or ProVoice Digital Mode.
ERROR Messages
If any of the following error messages are displayed, the radio was either programmed incorrectly
or needs servicing:
DSP ERR
ERR=xxxx DSP ERR DIGV ERR