Build Your Own Gateway Navigation:
Build Your Own Gateway – Welcome
Build Your Own Gateway – Part 1: What You’ll Need
Build Your Own Gateway – Part 2: Installing SVXLink
Build Your Own Gateway – Part 3: Configuring SVXLink
Build Your Own Gateway – Part 4: Connecting To The Radio
Build Your Own Gateway – Part 5: Programming the Radio
Build Your Own Gateway – Part 6: Connecting to the Reflector
Build Your Own Gateway – Part 7: Adjusting Audio Levels

Programming the gateway radio

To program the MTM800e gateway radio, you’ll need to connect your FTDI USB cable to your laptop/PC that’s running the Motorola Tetra CPS.

Ensure your FTDI cable connects to pins 19, 20 and 8 (ground) as per the details above in the PEI Data Connectivity – 3.3V FTDI Cable section.

Ensure the radio is powered off, then you’ll need to jumper pin 6 to pin 13 to put the radio in programming mode. Once the jumper is connected, power the radio on. You’ll notice that nothing appears on the display and the radio appears to be dead. It isn’t though! this is expected behaviour when the radio is in programming mode.

Next, on your laptop/PC running CPS, check which COM port is assigned to your FTDI cable using the Windows Device Manager. Typically this will be COM3 or COM4.

Then, within Tetra CPS go to Tools > Detect Radio on RS232 Port then enter the correct serial port number (e.g COM3) and click Detect

This may take a minute or two. If successful, the dialog box will turn green, and your radio will appear on the right side of CPS. To read your radio, simply right click it and choose Read Radio.

Note: If you’re running CPS on a virtual machine, you may notice that your USB FTDI cable keeps connecting and disconnecting. If this occurs, reconnect it by selecting it from the USB menu in your VM software.


Basic Programming

The basics you’ll need to get your gateway radio (MTM800e) up and running are below.

SectionSettingNotes
Subscriber Unit Parameters > Radio ISSI9999This ISSI is used for the gateway radio only. Don’t program this ISSI to any of your other radios.
Feature Flags > Direct Mode (DMO)TickedEnables DMO mode
DMO Parameters > DMO Address Extension > MCC901
DMO Parameters > DMO Address Extension > MNC16383
DMO Parameters >DMO MNI Partnership List > Country Code901
DMO Parameters >DMO MNI Partnership List > Network Code16383
TalkGroups > DMO > DMO Folders List > NameDMODisplay name for the DMO folder
TalkGroups > DMO > DMO Folders List > StatusTicked
TalkGroups > DMO > DMO Folders List > Transmission Timeout timer, sec300
TalkGroups > DMO > DMO Folders List > Transmission Timeout warning timer, sec280
TalkGroups > DMO > DMO Folders List > Number of talkgroups in range1This is the number of channels within the folder to display
TalkGroups > DMO > DMO Folders List > Receive OnlyNot ticked
TalkGroups > DMO > DMO talkgroup List > NameTETRA GATEWAYThis is the name of the channel that will appear on the display
TalkGroups > DMO > DMO talkgroup List > ID1
TalkGroups > DMO > DMO talkgroup List > StatusProgrammed
TalkGroups > DMO > DMO talkgroup List > DMO Folders ListDMOThe folder you created above
TalkGroups > DMO > DMO talkgroup List > Communication TypeDirect
TalkGroups > DMO > DMO talkgroup List > Gateway SelectionNone
TalkGroups > DMO > DMO talkgroup List > Gateway AddressBlankThis field will be blank
TalkGroups > DMO > DMO talkgroup List > Frequency Channel439.250This is the frequency your radio will transmit/receive at. Be sure to use a frequency within your licensing band.

If you cannot enter a frequency above 430, please see the note below.
TalkGroups > DMO > DMO talkgroup List > Receive Call to DMO Partnership NetworksUser Defined
TalkGroups > DMO > DMO talkgroup List > Network MCC901
TalkGroups > DMO > DMO talkgroup List > Network MNC 16383
TalkGroups > DMO > DMO talkgroup List > TMO Mappingblank
TalkGroups > DMO > DMO talkgroup List > Key GroupNO_KG
TalkGroups > DMO > DMO talkgroup List > Incoming Call security ClassSecurity Class 1
TalkGroups > DMO > DMO talkgroup List > Outgoing Call security classSecurity Class 1

Once you’re ready, write the changes to the radio, remove the jumper between pins 13 and 6, and then wait for the radio to power on.


Note: Increasing the frequency

It is possible to expand the transmit/receive frequency of your MTM800e. Do this at your own risk:

Within Tetra CPS Lab mode > Decimal (D) > cp_net_block > net_data > DMO_range

Change the min and max frequencies to suit. Keep in mind the radio starts to lose sensitivity 5 Mhz above and below the factory range. I have successfully extended both Motorola portable and mobile radios + / – 10Mhz without any adverse effects.


Note: Changing the power level

You can also use lab mode to change the power level of the radio from 3 watts to 400 milliwatts – which can be useful for testing.

Within Tetra CPS Lab mode > Decimal (D) > cp_hwconst_block > hwconst_data > 65 > tx_pwr_class_4l

Set this value to 1 to set power to 400 milliwatts, or 0 to set power to 3 watts.

Build Your Own Gateway – Part 6: Connecting to the Reflector >