Company Confidential
22
Raveon Technologies Corp.
Tune-up and Alignment
Do not key the transmitter for more than 30
seconds out of every 300 seconds. The
transmitter is rated at 10% duty cycle maximum.
The following table lists the parameters in the modem that are calibrated at
the factory. Calibration values are stored in registers R0 – R9. The
FireLine
radio modem has the capability of incorporating a variety of different radios
modules. Each different radio model is considered a different “radio type”.
The radio type is read and set with the ATR6 command.
Once you read a register using an ATRx command, you may modify its value
by entering a “U” for up or a “D” for down. U or D will change the value by
one. Use this trick carefully, because it modifies the last R register that was
read value, and it is easy to unintentionally modify the wrong register.
Typical Register Settings
R Register
R0
R5
R8
R9
Function
Peak Deviation
Preamble Length
Frequency Offset
Modulation Balance
Radio Type 2
(DM3473 Module)
-100
5
0
20
Radio Type 3
(DM3475 Module)
120
5
0
20
Center Frequency
1. Set the VCO balance setting to its nominal value. Use this command:
ATR9 20
2. Key the transmitter with CW output using this command:
ATTD 7
3. The modem will now put out CW on the center of the channel.
4. Read the frequency offset with the
ATR8
command.
5. Adjust the frequency to the center of the channel with the
ATR8
command. You can use the “U” key and the “D” key to change the
settings up and down one value in real time.
6. Set the deviation back to the value you read in step 1, using the
ATR0
command.
TX Deviation
1. Switch to channel 1.
2. Key the transmitter into a 50 ohm load using the ATTD 4 command.
The unit will now transmit, and send a digital 0 continuously. This
should be -2.0kHz low in frequency.