14: Maintenance
14-2
PRC1099A-MS
14.2
Measurement Techniques
The following information is provided for technicians and engineers who do
not have experience testing synthesized equipment.
14.2.1
RF Power Measurement
The PRC1099A RF power output is 20W PEP (peak envelope power) or
average power. The power output is 20W average in CW mode and has an
instantaneous peak output of 20W on voice peaks.
In CW mode or on a continuous sine wave tone, an average power meter such
as the Bird Model 43 indicates the correct output. On a voice signal, the meter
indicates an average power that is much lower than the peak power, typically
5W to 7W. On a two-tone test signal, the Bird Model 43 indicates a typical
power output of 8W (refer to Figure 14-1 on page 14-3 and Figure 14-2 on
page 14-4).
Measure the RF power output at the front panel 50 ohm BNC antenna
connector with no antenna mounted to the whip antenna connector—an
internal relay disconnects the 50 ohm connector when an antenna is connected
to the whip antenna connector.
The DC supply voltage should be at least 12V under load when making RF
power measurements. The current drain for voice operation is much lower
than when operating in CW mode. Even when the battery voltage is too low
for high power CW operation, there may be sufficient capacity for satisfactory
voice operation.
The RF power amplifiers in the PRC1099A are capable of 25W to 30W
output, however, Datron recommends that you do not set the power level
higher than 20W. You would have to at least double the output power before
you would notice any increase in transmission performance.
Optional
Oscilloscope
General purpose
Frequency response: 100 MHz
Audio Signal
Generator
Frequency range: 300 to 3000 Hz
RF Voltmeter
Frequency range: 0.5 to 100 MHz
Range: 10 mV to 3V
Spectrum
Analyzer
Frequency range: 1 to 105 MHz
Resolution: 100 Hz
Table 14-1 Test Equipment List
Equipment
Description
