AR 10052412, Operating And Service Manual

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Model 5000A225C
42 Rev A
3.4.3 A58 ALC
The A58 Level Control Assembly performs the following functions:
•
Provides automatic level control of the amplifier’s output when placed in ALC mode.
•
Limits RF input level to the amplifier when forward or reflected power levels exceed specified limits.
•
Drives forward and reflective indicators on the display panel.
3.5 SAMPLE PORTS
The signals appearing at the sample ports produce a level of approximately -13 dBm at 5000 W. Both forward
and reverse signals have the same scaling at this point. The sample ports are measured during final alignment
of the amplifier and a correction table is provided with enough measured points to adequately characterize the
sample ports across the full bandwidth of the amplifier. When used with a power meter, sample ports are
intended to be a general guide to the forward and reverse power being produced. If more accuracy or calibration
is required , an external directional coupler is recommended.