AR 600A400, Руководство по эксплуатации и обслуживанию

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Model 600A400
28 Rev A
3.4 CONTROL SYSTEM
3.4.1 A18 Control/Fault Board (Schematic #10042218)
The A12 Control/Fault board consists of one 16-bit microcontrollers and several other ICs that monitor and
indicate the status of the amplifier. Power is supplied using only a single 5-volt power supply. The board
offers the following:
Feature Quantity
Open drain outputs 4
Digital outputs 6
Digital inputs (5-volt tolerant) 24
Analog outputs 2
2-channel encoder input 1
Inputs for a keypad 6
Display connectors 1
Serial communication jacks 2
3.4.2 A20 Interface Board (Schematic #10020073)
The A20 Interface board connects the remote control ports to the A18 controller.
3.4.3 A17 ALC
The A17 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 -1dBm at 600W. 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.