System Considerations; Loss Indication - Motorola ASTRO XTL 2500 User Manual

System Considerations

• Trunked Systems only: If you press the PTT button when no
secure-voice channel is available, the display shows NO SECURE,
and a continuous talk-prohibit tone sounds until you release the
PTT button.
• Analog trunking systems: You are not allowed to change from
a secure transmission to a clear transmission during a secure
trunked call. If you attempt to change from a secure to a clear
transmission during a call, the radio generates a talk-prohibit tone,
and the display will show SEC ONLY or SECURE ONLY.
• Digital trunking systems: You are allowed to change from a
secure transmission to a clear transmission during a secure
trunked call.

Loss Indication

When you press the PTT button while in the coded mode and without
the encryption module containing a valid key, the speaker generates
bursts of alert tones, and the display shows KEY FAIL until you
release the PTT button.
When the radio is first turned on, six medium-pitched tones sound
and the display momentarily shows KEY FAIL to indicate that the
encryption module does not contain a valid key for the current mode.
If the periodic keyfail tone feature is enabled, six medium-pitched
tones are generated every five to ten seconds while the radio is not
transmitting or receiving to remind you that the radio does not have a
valid key for the current mode. The keyfail reminder will not sound
when the radio is in clear mode.
ASTRO XTL 2500 Digital Mobile Radio with M5 Control Head
Secure Operation
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