Tyco Electronics M/A-COM, M7300 Series 10.8 SCANNING CONVENTIONAL CHANNELS

If 5-Tone signaling is defined for emergency declaration in place of G-STAR emergency signaling, a pre-

programmed tone sequence will be transmitted instead of the G-STAR sequence. This emergency

declaration functions as the G-STAR emergency in all other respects.

In conventional mode, two keys can be defined to be tone encode triggers. If either one of the pre-

programmed tone encode triggers is pressed, a pre-programmed tone sequence will be transmitted on the

current system and channel. (See Section 10.7 if the emergency key is used.) The TX indicator will light

during tone transmission and a beep will sound at the end of the transmission. If enabled, audible side

tones will be heard in the radio speaker as well. If PTT is pre-programmed as one of the triggers, the

microphone will become active for voice communication after the tone sequence is complete.

Tone encode will be transmitted with Channel Guard if one is defined, and tones are always transmitted in

clear voice mode, even if the channel is set for digital or private (see VOICE MODES). Digital or private

voice transmission will resume normally after the tone transmission.

10.8 SCANNING CONVENTIONAL CHANNELS

Channels, which have been previously added to the scan list on a per system basis, can be scanned. The

selected channel is scanned (if enabled through programming) whether or not it is in the scan list. Each

conventional system's channel scan list is retained in memory when the radio is turned OFF.

The scan rate will vary depending upon the number of channels in the scan list and whether or not the

radio is programmed to scan for channels with decoding enabled. Fewer channels will result in a faster

scan rate. If programmed for dual-priority scan operation, the priority 1, priority 2 and the remaining scan

list channels are scanned. Once a signal is detected and the correct encoded squelch signal is decoded (if

programmed), the radio receives the message and displays the received scan channel. At the same time,

scanning continues on the priority 1 and priority 2 channels. If a priority 1 or priority 2 channel carrier,

regardless of encoded squelch decoding, is detected while a non-priority channel is being received, the

display name is updated and the received channel is switched to the priority channel. Scanning of the

priority-one channel will continue if a message is being received on the priority 2 channel.

While receiving a call on a non-priority or a priority 2 channel, the radio periodically checks the priority 1

and 2 channels. If Scan with Channel Guard is enabled, the radio will use Channel Guard to decide

whether to unmute on a priority channel. The radio stops, on squelch detection, on a priority channel. In

normal operation, the radio unmutes only on detecting the correct Channel Guard; otherwise, it remains

muted until the priority channel call and hang time have ended. An optional feature allows the radio to

continue scanning upon the detection of the wrong Channel Guard on a priority channel. The user can

then select the rate at which this channel is scanned until the call ends.

1. With scan operation turned OFF, select the desired channel to add to the selected conventional system

channel scan list.

2. Press (+) or (-) with to display the current scan status on line 1 of the display for a time-out

period.