AR 1000TP8G18 Series, Руководство по эксплуатации и обслуживанию

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Model 1000TP8G18
20 Rev -
damage the unit). The reverse power level should remain below 10% of the forward power, assuming that the
load is properly matched.
An alternate procedure is to pre-set the TWTA gain to minimum, set the RF generator to 0 dBm and then
slowly increase the TWTA gain to set the desired RF output level.
Observe that the helix current is sensitive to the RF drive level of the TWT. It is at a minimum with no RF
drive. The helix current with no drive and with rated RF power output mid-band are logged on the test data
sheet for a specific set of pulse input drive conditions. The value of the helix current under these drive
conditions is a good qualitative indicator of RF and video pulse drive input present.
To shut the system down, turn down the RF generator level below -50 dBm and press STANDBY. Allow the
TWTA to cool down until the TWT temperatures drops below 70°C, and then turn off main power.
3.7 REMOTE IEEE-488 OPERATION
The TWTA is provided with an IEEE-488 interface that permits remote emulation of OPERATE,
STANDBY, and RESET push-buttons as well as access to parameter measurements, system faults, gain
adjustment and control unit status. The Power Save mode (Sleep Mode) provides
remote capability to control
the TWT heater (filament) and to lower the amplifier standby power consumption during non-operational
intervals.
The following tables summarize the commands and the return codes.
Table 3-3. Catalog of IEEE-488 Commands
Command Function Units Response format
RDSTAT Returns status code of processing of previous command (see Table 3-4) STATUS=[ ]
RDFLT Returns system fault code (see Table 3-5) flt=[ ]
SYSTEM:ON; Emulates pressing the System ON button from System OFF (Exit Sleep
Mode)
SYSTEM:OFF; Emulates pressing the Power Save button. (Enter Sleep Mode)
OPERATE; Emulates OPERATE push-button
STANDBY; Emulate STANDBY push-button
POWER:OFF; Emulate STANDBY push-button
RESET; Emulates RESET softkey
RDS/N Returns serial number s/n=[ ]
RDCONHR Returns console hours ConHr=[ ]
RDRFHR Returns RF hours RfHr=[ ]
RDEK Returns cathode voltage KV Ek=[ ]
RDEB Returns collector voltage KV Eb=[ ]
RDEG Return grid voltage V Eg=[ ]
RDEF Returns heater voltage V Ef=[ ]
RDIF Returns heater current A If=[ ]
RDIW Returns helix current mA Iw=[ ]
RDTMPTWTF Returns TWT temp (°F) °F TWTF=[ ]F
RDTMPTWTC Returns TWT temp (°C) °C TWTC=[ ]C
RDTMPPSF Returns power supply temp (°F) °F PSF=[ ]F
RDTMPPSC Returns power supply temp (°C) °C PSC=[ ]C