AR 1000TP8G18 Series, Operating And Service Manual

Page: 45 / 74

Rev - 27
4. MAINTENANCE
The TWTA requires a minimum of routine maintenance . The only moving parts are the elements of switches,
relays and blowers. Preventive maintenance is recommended in Section 4.3.
In the event that the TWTA needs repairs, it is recommended that the unit be returned to the factory.
However, some user service organizations may choose to perform their own corrective maintenance, and
under some circumstances returning the unit to the factory may be impractical. The highly modular
construction of the TWTA facilitates troubleshooting to the level of readily replaced subassemblies. Section 5
provides partial technical documentation to support field repairs. Nevertheless, the factory or its service
representative should be contacted before undertaking repair work on these TWTAs.
Warnings and
Cautions must be observed.
4.1 SAFETY WARNING
WARNING:
Service work must be performed only by technicians thoroughly familiar
with the high voltages present in microwave tube amplifiers in general,
and with this equipment in particular.
Never handle the TWT leads or the high-voltage connectors unless it has
been positively established that the high-voltage filter capacitors have
been discharged to a known safe level.
CAUTION:
A malfunctioning power supply can cause damage to the TWT. If you are
troubleshooting the TWTA, remove the TWT and substitute suitable
loads to prevent damage to the TWT.
4.2 UNAUTHORIZED REPAIRS
CAUTION:
Unauthorized repairs or modification of this product during the warranty
period may void the warranty. In the event that the TWTA malfunctions
while it is still under warranty, always contact an authorized service
representative.
4.3 PREVENTIVE MAINTENANCE
The RF characteristics and power supply voltages and currents of the amplifier should be logged on a regular
basis. Maintenance should be performed if significant deviations from the logged values appear. If the unit is
under warranty, contact an authorized service representative if impaired performance is suspected.
If there is accumulated dust on the air intake grill clean it with dry compressed air.
If significant dust has been noted on the air intake grill it may be desirable to vacuum the dust and debris from
inside the enclosure.