Operating instructions

LOCAL OPERATION
3-26 46882-311D
WARNING
Hot surfaces
Take care when touching the RF Input Type N connector after the application of high levels of
continuous power. If 50 W is applied for a prolonged period, the temperature of the connector
can become excessive.
With the monitor in the Tx TEST mode, and the transmitter connected to the monitor as
described above, key up the transmitter.
The RF power bar chart gives an analogue representation of the active power meter reading. A
digital read-out of the power is displayed above the bar chart.
The options available for the digital read-out from the power meter are dBm, Watts or Volts.
The bar chart can be auto-ranging or manually selected. See
Bar charts on page 3-13.
External attenuators can be included in the input path to the Service Monitor. The value of any
such attenuators can be entered into Setup Page 1 of the Service Monitor, which will cause the
power measurement software to calculate the power at the attenuator input. The result of this
calculation is shown on the RF power bar chart and as the digital power reading.
Power readings which include an attenuation factor have an inverse video ’A’ adjacent to them.
The full-scale ranges of the RF power bar chart, are:-
10 mW to 100 kW in 15 steps of 1-3-10 sequence.
100 mV to 3 kV in 16 steps of 1-3-10 sequence.
Directional power measurements
Directional power and VSWR measurements can be made using the optional Directional Power
Head accessory or Light-weight Directional Power Head accessory. The
DIRECTIONAL POWER
METER
screen, accessed by pressing the [Dir Power] key, is used with these accessories. To leave
the
DIRECTIONAL POWER METER display and return to the Tx test mode display, press the [Tx
TEST] key. See Appendices A and B.
RF harmonic analysis
The harmonic content of a transmitter output can be analysed using the harmonic analyzer
function.
B3197
Fig. 3-5 Tx power, harmonic analysis screen
To obtain an analysis of a signal, proceed as for making a power level reading. With the power
level of the signal to be analysed displayed, press the [Harmonc Analys] key. The screen shown
in Fig. 3-5, Tx power, harmonic analysis screen, is displayed. The power level bar chart shows
the power output of the transmitter as before. The harmonic content of the signal is shown on the
HARMONICS bar charts. These four bar charts are each given to progressive harmonics of the
fundamental frequency of the signal. They are graduated in dB relative to the carrier level (dBc),
from 0 to -80 dBc.