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6.3.2 Leveling On A Constant E-Field Using Sensors
In order to avoid a potential RF radiation hazard condition during these initial set up procedures, it is
best to operate on the lowest field intensity range ( 0 to 3 V/M ). It is also advisable to use an initial
test frequency less than 10 MHz. This will avoid the complications of reflected fields and room
resonances.
The Test Set-Up Procedure, refer to Figure 8.0 for a Typical ‘E’ Field Leveling set-up
1) Connect the RF Output of the Signal Generator to the RF Input of the SMX100.
2) Connect the RF Output of the SMX100, located on the same panel as the RF Input connector, to
the antenna.
3) Connect the ALC Input, located in the rear panel of the SMX100, to the output of the Light
Demodulator Indicator, IFI P/N LDI. Refer to Figure 2.0, SMX100 Rear Panel Illustration, for
location of the ALC Input.
4) Connect a Light Pipe to the Input of the Light Demodulator Indicator, IFI P/N LDI, and to the
LMT output of an IFI ‘E’ Field Sensor.
Leveling Procedure
1) Turn on all equipment shown in Figure 8.0 and allow a three minute warm-up period.
2) Turn the RF Level Adjust fully clockwise to the maximum gain setting and set the tracking of the
EFS and LDI to a suitable input drive level required to obtain a full scale reading.
3) Turn the RF level adjust fully counter clockwise to the minimum gain setting and set the ALC
switch to the EXT position making sure that the LDI is properly attached to the ALC port
located in the rear of the unit.
4) Turn the RF Level Adjust on the front panel to the desired field level for leveling. The desired
level should automatically be maintained within 1 dB for each 20 dB change in the input drive.
5) If the leveling loop should exhibit an unstable condition, vary the RF Signal Generator output
until the indication stabilizes and is maintainable.
