BIRD 43 - Chapter 4 Operating Instructions; Normal Operation

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Chapter 4 Operating Instructions
The Bird 43 uses plug-in elements to make measurements. The
element’s frequency range and maximum power are listed on its label.
The transmitter test frequency should be within the band of the
element used. See “Frequency Response” on page 14 for information
on using the elements outside of their specified frequency range.
The arrow on the element indicates directional sensitivity; i.e., the
direction of power flow that the meter will read. Rotate the element to
select forward or reverse power measurement.
Combining the Thruline Wattmeter with a Bird Termaline Load
Resistor creates an accurate absorption wattmeter. With this
combination, readings only need to be taken in the forward direction
because the reflected power will be negligible.
Normal Operation
y Insert the appropriate element in the line section socket.
y Turn the element so that the arrow points towards the load to
measure forward power and towards the source for reflected power.
WARNING
When working with RF powers of 200 watts or more, the potential of
the center conductor of the line section will exceed 100 volts. Do not
touch the center conductor while RF power is on.