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5.2.2 Power Amplifier - continued
This amplifier consists of four amplification sections, the final stage having four cascaded high-
power, push-pull devices operating in parallel and combined through a transmission type impedance
transformer.
5.3 MANUAL LEVEL CONTROL (Option)
Manual level control is accomplished by adjusting the front panel ten-turn potentiometer, located on
the power supply control unit, to a reference voltage setting between 0 to 5 volts.
5.3.1 Automatic Level Control (Option)
In this mode, the SMX100 serves as the voltage comparator and variable gain stage. It will enable
the maintenance of a constant RF voltage vs. frequency at the input to an imperfect load or a virtually
constant E-Field at a measurement point in space. For further information regarding the ALC
operation, refer to Section 6.0.
5.4 OPTIONAL FEATURES
5.4.1 Interlock Feature
The Interlock Feature is an option for the SMX100 that utilizes an Electro Magnetic Interference
(EMI) Testing Room door switch that is mounted to the door in such a manner that when opened, the
switch will automatically induce an ordered shut down of the amplifier and produce a STAND-BY
MODE indication on the LCD Metering Display. When the door is closed, the amplifier resumes
previous testing conditions.
The advantage to this feature is providing an additional safety feature for the growing concerns for
potential hazards due to exposure to EMI Fields. With the Interlock option, all Testing Personnel
will be protected from accidental exposure to EMI Fields. Should the operator desire this optional
feature, the amplifier can be returned to IFI for installation. Refer to Section 8.0 for Equipment
Return Procedure.
