EFJohnson 764X, 761X service manual Channel Scan

CODE

OPERATION

3.5.15 SCAN LIST PROGRAMMING

Pressing the TAG key changes the scan list sta- tus of the current channel. Refer to the scan list description in Section 3.6.2 for more information.

3.5.16 TALK-AROUND SELECT

The talk-around mode causes transmissions to occur on the receive frequency to permit direct mobile-to-mobile communication when a repeater is being used. The talk-around mode is turned on and off by pressing the TA key. Either “AR ON” or “AR

OF” is briefly displayed to indicate the current mode. Changing the channel or turning power off causes talk- around to revert to the off condition.

3.5.17 2-TONE CALLING FEATURES

If the optional 2-tone signaling option is used, pressing the CALL key transmits the 2-tone codes on

the selected channel or on a non-busy channel if pressed while scanning.

3.5.18 5-TONE CALLING FEATURES

If the optional 5-tone signaling option is used, the following keys may be programmed to control various functions.

CALL CAL A CAL B - Transmit the 5-tone call. Depending on your signaling system, call transmission may be necessary before you call another station. The CAL A and CAL B keys may be programmed when selective Individual/Group calls are used.

TX CH - Selects the 5-tone code to be transmitted. To change the contents of the station code, push and hold

this key and then press the keys.

- Selects the transmit code directory.

MR CH - Recalls last five codes received. Press and

hold to erase all codes. To scroll, press .

3.5.19 WIDE/NARROW BAND SELECT

Pressing the W/N key switches the receiver

between narrowband and wideband operation. The

display briefly indicates “WIDE” or “NARROW” to indicate the current mode. Each channel can also be programmed for wide or narrow band operation, and this switch toggles that setting. However, the change is only temporary because the programmed condition is reselected if the channel is changed or power is cycled.

3.6 CHANNEL SCAN

3.6.1 INTRODUCTION

The channel scan feature monitors the channels in the current scan list. When a message is detected that the transceiver is programmed to receive, scanning stops and the message is received. Shortly after the message is complete, scanning resumes (after the resume timer counts down). The selected channel changes to that of the call.

If the microphone is taken off-hook or the trans- mitter is keyed while scanning, scanning resumes when the auto reset timer selected for the channel counts down. Scanning does restart if this timer is dis- abled or if the Scan A key is programmed with power- on scan disabled (see Tables 4-2and 4-5).

Scanning is turned on and off by the SCAN key. The transceiver also may be programmed so that scan- ning automatically turns on whenever power is turned on or the microphone is placed on-hook. The micro- phone must be on-hook for scanning to occur.

The decimal point in the display flashes when the scan mode is enabled. Then when scanning is actually occurring, either the scan list identification (see next section) or the rapidly cycling channel identification is displayed as the channels are scanned. Programming determines which occurs (see Table 4-5).

3.6.2 SCAN LISTS

Up to five scan lists can be selected by pressing and holding the SCAN key until the scan list identifi-

cation appears and then pressing the keys. Press the SCAN key again to exit this mode (this also

occurs automatically in about 30 seconds) and again to enable scanning (if desired).

	November 1998
3-7	Part No. 001-7600-001