MFJ-269D Instruction Manual LF/HF/VHF/UHF SWR Analyzer
8
4. Inductance in
µ
H:
The fourth mode,
Frequency
appears on top and
X
L
(inductive reactance) on the
bottom. Meter shows reactance (
X
).
5. Freq. Counter:
The fifth function turns off the analyzer's internal oscillator and routes the input of the
counter to the BNC connector labeled
Frequency Counter Input.
In this mode, the top line of the LCD
display shows the measured
Frequency
in MHz and the counter's
Gate Time
in seconds.
Important Note:
Section-4 of this manual provides detailed instructions for using each of the five basic
operating modes described above. To ensure accurate measurement and avoid the possibility of
inadvertent damage, please read through this section carefully before operating the analyzer!
3.4
Frequency Control
The MFJ-269D tunable RF-oscillator covers an exceptionally wide frequency span, using two rotary
band switches for
LF/HF/VHF
coverage (0.10-230 MHz) -- plus an additional pushbutton switch to
activate
UHF
coverage (415-470 MHz) .
1. LF, HF and VHF Operation:
The
Lower Range
rotary switch selects four LF and HF bands (0.10-
11.0 MHz). The
Upper Range
switch selects 5 HF and VHF bands for 11-230 MHz coverage. Note that
the
Upper Range
switch must be set
fully clockwise
to the
Lower Range
position for the lower-range
band selector to function. The variable
Tune
control (VFO capacitor) provides a small overlap at each
band edge to ensure gap-free tuning across the spectrum.
2. UHF Operation:
UHF coverage is broken into two bands. To measure
UHF
SWR (415-490 MHz),
first press in the
UHF
switch located just above the LCD display. Then, for
415-470 MHz
coverage, set
the upper
Frequency MHz
switch to the
113-155 MHz
band (
UHF LO
). For
470-490 MHz
coverage,
set the upper
Frequency MHz
switch to
155-230 MHz
.
(UHF HI).
It is normal for the VFO's
Tune
range to exceed the analyzer's usable
UHF
measurement range. If the
VFO frequency is out of range in UHF Mode, one of the error messages shown below will instruct you to
increase or decrease frequency to bring it back in range:
Adjust
Tune
clockwise
to
increase frequency
and
counterclockwise
to
decrease frequency
. When in
range, the operating
Frequency
will appear on the top line of the LCD display -- along with the
SWR
reading. The bottom display line becomes an analog
SWR bar-graph
(see below).
445.75 MHz 1.3
INCREASE
FREQUENCY
DECREASE
FREQUENCY