TECHNICAL NOTE – OPERATION OF MT4000 TWTA
10/24/03
TN4000-3
MCL, INC.
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4.5.2.2 Conditions That Will Prevent Auto Power From Turning On
The HPA will refuse to perform an Auto Power command if any of the following conditions are
present.
If the TWTA is not in Transmit.
If the Forward power sample is 0000W.
If the Computer or Remote interface were to set the Auto power level to 0006W
or less.
If RF is Off.
4.5.2.3 Conditions That Will Suspend Auto Power
When the HPA is in Auto Power, it will stop all Auto Power attenuator action while the HPA is
in the RF Off state. The HPA will remain in the Auto Power state but no attenuator action will be
taken while in the RF Off state. The Auto Power attenuator action will resume once the HPA is
placed back into RF On.
4.5.2.4 Conditions That Will Turn Off Auto Power
The HPA will terminate the Auto Power function if it is active when any of the following
conditions occur.
The set Auto Power level exceeds the top Forward Power calibration point.
If the TWTA drops out of Transmit.
If a Disable Auto Power command is received while the TWTA is in the
Computer or Remote mode.
If the Forward power sample is 0000W.
If the operator at the Local panel were to press the Hold Power button again.
If the Computer or Remote interface were to set the Auto power level to 0000W.
If the RF attenuator is manually adjusted.
4.5.3 Hold
Power
The MT4000 front panel contains a Hold Power control and indicator, which will be used to
control the Auto Power Function. The operator will set the RF output power using the Gain
Adjust Screen. Once he has obtained the desired power level he will press the Hold Power
button. The LED in the Hold Power button will illuminate and the Auto Power function will
regulate the RF output power to the level currently displayed on the RF Forward Power display
(meter). If the operator were to press the Hold Power button again the Auto Power regulation
function will turn off. Equivalent commands have been provided on the Computer & Remote
interfaces.
