User's Manual

Table Of Contents

MX800 Transceiver Installation & Operation

2.3.2.3 Select Operating Channel

The MX800 has a channel capacity of 255. The RF and CTCSS frequencies

for each channel are programmed using MXTOOLS Channel Information

screen. There are four ways of selecting the operating channel.

1. DIP Switch 8-way. DIP switch SW1 provides a binary channel selection

facility. When a switch is ON it is read as a logical 1. When all switches

are off the software channel select mode is enabled.

2. Rear channel select port. Digital input port B provides an 8 way Binary

or BCD channel select input. Binary or BCD coding is selected using

MXTOOLS. If Binary is selected 255 channels are accessible. If BCD is

selected 99 channels are accessible.

3. Software channel select. If DIP switch SW1is set to 0 then it is possible

to send a software command to the radio to select the channel.

4. Front panel Push-wheel switches. If this option is fitted the rear channel

select port is internally wired to the Push-wheel switches however the

rear channel select function is still in parallel with the Push-wheel. The

rear select method should not be used in this case. There are 100

channels selectable from the front panel. The same rules apply to this

channel select method as apply to the rear port described below. BCD

Coding is selected using MXTOOLS.

The following rules apply.

(The assumptions of logic levels are base on factory default setup. The

Active state is Low)

DIP1 switches have priority over channel change. If any of DIP1 switches

are set to ON (logic low) the rear inputs and the software Channel command

will be ignored.

If DIP1 switches are set to OFF (logic high) then both the software

commands and the rear input port would select the channel. In this case the

most recent event will take priority. For example, if the rear input port is set

to CH10 and a software command arrives to send it to CH15, the radio will

go to CH15. If the rear input port is now changed to CH11 the radio will

switch to CH11.

If DIP switches are set to OFF and the radio is powered up, the channel

selected on the rear port will be adopted.

If DIP1 switches and the rear port are both set to OFF (logic High), on power

up, the radio will adopt the last software channel selected. This may be the

software channel set at the factory if the user has not used the software

channel select feature before.

2.3.2.4 Configure Alarms/M Lead

The MX800 has 3 open collector outputs. Two of these are assigned as alarm

outputs and one (output 1) may be configured as either an alarm output or an

M Lead output. If the output one is configured as an M Lead, this line is

active when mute is open and CTCSS/DCS is decoded. These outputs are

assigned in the Configuration screen of MXTOOLS.