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6.
Send the following command to the radio via the terminal application:
at***** <maximum transmit power>
where <maximum transmit power> equals the required
maximum transmit RF output power level in dBm. A space is required after at*****.
For example, to set the maximum power to 10 watts (40 dBm), send
at***** 40
to the radio.
Use the following formula to convert watts to dBm:
dBm = 10 x Log
10
(milliwatts)
, where
1 watt = 1000 milliwatts (1 milliwatt = 0 dBm).
7.
Send the following command to the radio so it will reboot and the new power setting will take effect:
atz
8.
Disconnect the programming equipment and continue with the test procedure presented in the next
section.
15.4 TRANSMITTING INTO A DUMMY LOAD
1.
Using the Type N male to TNC male RF coaxial jumper cable, connect the radio’s antenna connector
to the wattmeter’s input connector. Refer to Figure 15-2 as necessary.
2.
Connect the 50-ohm dummy load to the wattmeter’s output connector, in place of the antenna cable
from the mounted mobile antenna.
As previously stated, if conventional mode is not available per radio programming
(i.e., OTP mode is available but ECP mode is not), a peak-reading RF wattmeter is
required to measure RF transmit power. Otherwise, the use of an average-responding
wattmeter is recommended. Recommended wattmeter types are listed in Table 15-1.
3.
If not already, turn the radio on and set it to the required operating mode (based upon available radio
programming and test equipment). Refer to Section 15.1 as necessary.
4.
Set the radio to a test talk group or conventional channel, if available.
It is recommended that a test talk group/channel be allocated for this testing. This
same group should be used during the antenna test procedure which is presented in the
subsequent section.
5.
Position the wattmeter’s slug to measure forward RF output power. Rotate it if necessary. The arrow
on the face of the slug must point away from the radio and towards the dummy load for forward
power measurements.
6.
For conventional mode transmissions
, set the wattmeter to measure average RF power.
For OpenSky mode transmissions
, set the wattmeter to measure peak RF power.
7.
Key the radio’s transmitter via the microphone’s PTT button.
8.
Verify the measured forward RF output power into the dummy load is within 20% of the maximum
transmit output power (in watts) programming performed per Section 15.3.
Transmit only for as long as needed to take the measurement, then immediately
disable the transmission.
