User Manual

22 Raveon Technologies Corp.
10. Tune-up and Alignment
The RV-D80-EB/RV-M80-EB modem has been factory calibrated, in should not
require any re-calibration when installed, or when changing frequency or
channel. Unless the user is trained in radio test and calibration, the values
stored in the R registers should not be modified. Radio calibration and alignment
is performed using the ATRx commands.
Improper adjustment of the radio calibration (R0-R9 and RA registers), can
result in failure of the radio modem.
Calibration and alignment values are stored internal to the modem in the “R”
registers. (R0-R9 and RA). For example, to read R5, issue the ATR8 command
without any parameter. To change the setting, issue the ATR8 nn command,
where nn is the new value you would like to store.
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, and it is
easy to unintentionally modify the wrong register.
10.1. Periodic Calibration
The only setting that may require adjustment is the center frequency. After years
of operation, all crystals will age and change frequency slightly. The ATR8
command is used to adjust the center frequency. Like all narrow-band radios,
semi-annual checks and adjustment of frequency is recommended.