132 FieldFox User’s Guide
Please observe the RF IN port damage level.
+27 dBm (320 mW) average
+33 dBm peak (2 W) <10μs
+50 VDC
Frequency/ Span / Step
Valid CPM measurements can be made over the entire frequency range of the
FieldFox. Although it is possible to enter a center frequency below the FieldFox
minimum frequency, the LO feed-thru of the internal SA hardware will invalidate
these CPM measurements.
The measurement span (also known as Channel Width and Integration BW) is the
frequency range, half above and half below the center frequency, over which
power is detected and displayed. The maximum measurement span is 100 MHz.
A Radio Standard can also be used to set the center frequency and span. Learn
more about Radio Standards on page 78.
How to enter center frequency, step size, and span
The default frequency is 50 MHz.
Press Freq/Dist or Meas Setup 4 .
Then Frequency.
Then Center
Then type a value using the numeric keypad. Then press a multiplier key.
Learn about multiplier abbreviations on page 19. The current frequency (f) is
shown on the FieldFox screen.
Optionally, use the ▲|▼ arrows to quickly change Center frequency. The size
of the frequency step can also be changed. Press CF Step then type a step size
value using the numeric keypad, then select a multiplier key.
Optionally press Span (Ch Wid) Type a value using the numeric keypad. Then
press a multiplier key. The default span is 2 MHz. The maximum span is 100
MHz. The current span setting is shown as the dividend in the digital display.
For example: -10 dBm / 1.00 MHz
Attenuation
The Attenuation setting controls the power level into the FieldFox.
To compare CPM mode measurements to SA Channel Power measurements, use
the same attenuation settings. CPM mode defaults to 30 dB attenuation, while SA
mode defaults to 10 dB attention. In CPM mode, the attenuation setting is NOT
annotated on the screen.
How to set Attenuation
Press Scale/Amptd
Then More
Then Internal Atten