MFJ-269D Instruction Manual LF/HF/VHF/UHF SWR Analyzer
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5.4.2.1
Return Loss and Reflection Coefficient (UHF)
Return Loss and Reflection Coefficient
is the first measurement mode in the
Advanced-1
UHF
menu.
To access this menu, press and hold
Gate
and
Mode
simultaneously until
Advanced-1
appears (same as
LF/HF/VHF entry). The display will briefly indicate:
After a few seconds, the opening display changes to the data screen (samples below). Note that SWR
greater than 5:1 falls beyond the measurement range of the MFJ-269D in UHF mode.
The
Return Loss and Reflection Coeff
mode measures and displays
Return Loss
in dB and
Voltage
Reflection Coefficient
on the LCD. These terms are another way of describing SWR. The SWR meter
indicates SWR normalized to 50-Ohms, and the impedance meter is disabled. To use this mode, connect
the DUT to the
Antenna
connector, adjust
Frequency
as needed, and read the results on the screen and
SWR
analog meter display.
5.4.2.2
Match Efficiency (UHF)
Match Efficiency
is the second and final measurement available in the
Advanced-1 UHF
menu. To
access it, first enter the Advanced-1 menu, then press and release
Mode
one time. You can also reach it
by stepping through the other
Advanced-1
modes until the screen displays
Match Efficiency
.
Match efficiency, yet another way of describing SWR, is similar to mismatch loss, but the data is
expressed as a
Percentage of Forward Power
vs.
Reactive
or
Circulating Power
in the system.
Important Note:
Match efficiency
may mislead those unfamiliar with SWR and energy transfer in a RF
system. See note under 5.4.1.6 for an expanded explanation.
Sample screens: