MFJ-269D Instruction Manual LF/HF/VHF/UHF SWR Analyzer
26
4.
Press
Mode
again. The
Line Length in Feet
screen appears:
5.
It then quickly changes to the data screen showing
Line Length
for the electrical degrees entered
(default is 360 degrees) for the velocity factor entered in step 1. Adjust
Frequency
, and the analyzer
will recalculate the correct length for any frequency desired (sample screen):
6.
Pressing
Mode
shifts the display back to the
Velocity Factor
adjustment screen in step 2. Pressing
Gate
takes the display to a
Line Length
adjustment function that allows you to change the length in
degrees.
Line length ?
l = 360
o
7.
To increase line length in degrees, press
Gate
. To decrease it, press
Mode
. When the desired length
appears, simultaneously press and hold
Gate
and
Mode
to lock it in. The display will now change to:
Line length ?
l = 78
o
Pressing
Mode
shifts the display to the
Velocity Factor
adjustment in step 2.
5.6
Advanced 3 (LF/HF/VHF only)
To access this mode, press and hold
Mode
and
Gate
until
Advanced-3
appears on the display.
Advanced-3 is used for setting the SWR reference impedance to values other than 50 ohms, and to
measure line loss and SWR in systems other than 50 ohms.
Advanced 3
Note:
The analog
SWR Meter
does not change reference impedance in this mode. It continues to display
the 50-ohm normalized value. Only the display SWR changes.
5.6.1
Z Characteristic
After entering
Advanced-3
, the display changes to a default setting of
Zo= 75
. It also prompts the
operator to enter a different value (
Z Characteristic?
).
1.
Zo
may be re-set using
Gate
to
increase
or
Mode
to
decrease
the normalized impedance value.
2.
After selecting a new
Zo
,
press both
Mode
and
Gate
simultaneously to lock it in The display will
show (sample screen):
Z Characteristic?
Z = 35
0