CPI T04CO, Installation & Operation Manual

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M P A H U B M O U N T
5.5 Making Routine Safety Checks
It is very important that the user confirm the Hub Mount MPA trip
settings. These have been set at the factory for checkout of this Hub
Mount MPA . Verification of the trip settings should be made more
often if the equipment has been used by several operators. Failure
to operate the Hub Mount MPA with the correct settings can result
in damage that is not covered by the warranty. For this reason, the
procedure that changes the trip settings should be given only to
authorized personnel.
5.6 Description of Amplifier States
The operation of the Hub Mount MPA may be divided into several
states and sequences. They are as follows:
POST (Power On Self Test)-Initial power on.
HTD (Heater Time Delay)-Beam off state while cathode heats to
operating temperature.
STANDBY-Normal beam off state. (High Voltage not applied to
the TWT.)
BONS (Beam On Sequence)-Transition from the STANDBY state
(beam off) to the TRANSMIT state (beam on).
TRANSMIT-Beam on state (in this state, the Hub Mount MPA
amplifies the RF input signal to the rated output level).
BOFS (Beam Off Sequence)-Transition from TRANSMIT state to
any beam-off state.
Fault (Non-latched)-Beam-off malfunction state; the amplifier will
automatically recycle to the state that existed prior to the fault.
Fault (Latched)-Beam-off malfunction state. User intervention
required to return the amplifier to a normal operating state.
Doc. 01031254 Rev. 1
5-5