This article describes how to do a functional test of the Raveon M7 data radio modem.  The M7 is a UHF or VHF radio modem, and using Raveon’s free RadioManger software M7 data radio modems can be quickly tested/validated ensuring they are communicating well. The tests described in this article will be useful for:

1. Capturing the configuration / settings of the radio modem to a file.
2. Verifying the radio modem is transmitting the correct RF power output level.
3. The frequency of the radio modem is correctly set.
4. The serial port parameters are correct
5. The over-the-air baud rate is correct and compatible with the system the modem will be used in.
6. Verifying and recording the DC power consumption
7. Determining the packet-error-rate on the bench or in the field.

A quick functional test is HIGHLY recommended on every radio modem before it is deployed in the field.  These same functional tests can also be used to bench-test a radio modem that is suspected to be damaged or operating improperly. A lot of time can be saved by catching human errors, configuration problems, and component failures before the unit is deployed in the field.  Below is a diagram of how to connect two radio modems to perform the test.  Radio A is the radio to test, but this setup will validate that both radio A and B are communicating well.

Radio Modem Test Configuration

Remember: Out of the box all Raveon data radio modems just work.  Connect power, serial ports, antennas, and they will communicate. Raveon tests 100% of all radios shipped to our customer for full functionality, plus verifies communication reliability.  Raveon also provides a customization service for customers who would like their radio modems custom-configured. When you receive modems from Raveon, you know they work together, and if you setup this test, you will quickly verify this.  It is good practice to start with this verification, then make any modification to the configuration of the radio modem’s parameters that you need to, and then re-do the test to verify that your new configuration works as expected.

Step 1 – Setup the Test Equipment

Begin by installing RadioManger onto a computer that has an RS232 serial port.  If the computer does not have an RS232 serial port, then use a USB serial bridge to convert a USB port to serial.

Connect the radios to test as show above in the Radio Modem Test Configuration diagram. The RF attenuators are typically 40dB pads. They avoid transmitting large amounts of RF power on the air. For this test, the radios are placed on the same test bench. Antennas should be connected to the attenuators, or directly connect the two attenuators together with a coax cable.

“Radio A” is the radio modem device under test (DUT).  The DUT is the unit that will be tested, recorded, and verified that it is operating properly.

“Radio B” in the test above should be a known good working radio modem, properly configured to the specifications of the system.

Step 2 – Configure the Device Under Test (DUT)

The M7 data radio modem has a lot of user-configurable parameters.  All commands and parameters are documented in the product’s Technical Manual available <here>. The most common parameters that will be configured on a radio modem are:

A. Frequency  (ATFX, ATFR, ATFT )
B. ID  (ATMY)
C. Serial port baud rate (ATBD)
D. RF power level  (ATPO)
E. Over-the-air baud rate  (ATR2)
F. Destination ID  (TOID)
G. Address mask  (ATMK)

Refer to the technical manual for information on how to set configure these parameters, and any others you wish to configure.

Step 3 – Record the Settings

There are two easy ways you can record the DUT’s configuration to a file.  1) Have RadioManager read them, and store them in the .xdat format.  2)display them using the config command, and copy/paste the displayed configuration to a text file.

Using RadioManager:

• Turn the DC power supply on.
• Start RadioManager
• Select the serial port on RadioManager that the DUT is connected to. Set RadioManager’s serial port settings to match the DUT’s serial port settings.
• Click the “Discover Radio” button.
• Once RadioManger has discovered and connected to the DUT, click “Read Settings from Radio”
• Once the settings have been read into RadioManager, click File > Save Settings  and store them to the .xdat file.

At a later time, you can recall these stetting, and load them back into the radio or into another radio.

Storing the Configuration into a Text File:

• Turn the DC power supply on.
• Start RadioManager (or any terminal program such as Terraterm or Hyperterminal)
• Select the serial port on RadioManager that the DUT is connected to. Set RadioManager’s serial port settings to match the DUT’s serial port settings.
• Click the “Discover Radio” button.
• Once RadioManger has discovered and connected to the DUT, click on the terminal window in the lower right corner of RadioManager.
• In the terminal window, type the phrase “CONFIG” without the quotes, and press enter.
• The DUT will output all of its configuration settings, and they will appear in the terminal window.
• Type ctrl A then ctrl C to copy them to the clipboard of the PC.
• Open a text file using notepad, word, or some text editor, and paste the clipboard into the file.
• Save the file

Step 4 – Electrical Tests

RF Power:

• Turn the DC power supply on.
• Start RadioManager
• Click the “Discover Radio” button.
• Once connected and communicating with the DUT, click on the terminal window in RadioManager
• Type ATTD 3 to force the Radio A transmitter to key up sending random data.
• Adjust the RF power to the desired level with the ATPO command.
• Measure and record the RF power level.
• Measure and record the DC current draw as seen on the amp-meter of the DC power supply.
• Press the enter key to un-key the Radio A transmitter.

Character Echo:

Note, this test can only be done when Radio B is also configured to communicate with Radio B.  The RX and TX frequencies must be compatible.  The IDs and address masks must be set so that A and B can communicate.  On many systems, this is the normal configuration, but on some systems, radio modems only communicate one-way or with only one other radio modem.  Plan this test so that Radio B can communicate properly with Radio A.

• Turn the DC power supply on.
• Start RadioManager
• Click the “Discover Radio” button.
• Once connected and communicating with the DUT, click on the terminal window in RadioManager
• Type any character on the keyboard.  Radio A’s STAT LED should blink red every time a character is typed, indicating the character is transmitted over-the-air.
• Radio B’s STAT LED should blink green indicating it received the character.
• Because of the loop-back wire on pins 2-3 of Radio B, Radio B will also transmit back the character to Radio A.
• When Radio A receives the looped-back character, it will output out of its serial port and it will appear in the RadioManager terminal window.

Packet Error Rate:

Note, this test can only be done when Radio B is also configured to communicate with Radio B.  The RX and TX frequencies must be compatible.  The IDs and address masks must be set so that A and B can communicate.  On many systems, this is the normal configuration, but on some systems, radio modems only communicate one-way or with only one other radio modem.  Plan this test so that Radio B can communicate properly with Radio A.

On the bench, the packet error rate will be zero.  You may put Radio A on the real antenna to be used in the system, and Radio B at a remote site in the system, just to test the error rate to the remote site as the system will operate.

• Turn the DC power supply on.
• Start RadioManager
• Click the “Discover Radio” button.
• Once connected and communicating with the DUT, click on View > Expert to put RadioManger into the Expert mode.
• Click View > BERT to bring up the packet error test window.
• Set the interval to the desired test rate. 1000mS is typical for the short ABC test packet.
• Set the test packet to use.
• Click “Start”
• Radio A’s stat LED will blink at the packet rate, each time it transmits.
• The BERT window will count transmitted packets and received packets, and display the statistics.
• Let the test run as long as you wish, record the results if desired.

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