MFJ-269D Instruction Manual LF/HF/VHF/UHF SWR Analyzer
6
Never attempt to charge alkaline (or any other non-rechargeable cells) using the MFJ-269D's internal
charger circuit!
2.5
“Voltage Low” display warning
When the analyzer's supply or battery voltage drops below 11 volts, a blinking
Voltage Low
warning
will be displayed. Pressing
Mode
during a low-voltage warning will disable the on-screen alert and allow
you to continue operating. However, measurements may not be reliable when operating the analyzer with
insufficient supply voltage!
2.6
Sleep Mode “Power Saving”
Typical current drain for the MFJ-269D is around 150 mA for HF operation (250 mA for UHF). Battery
operating time is (by default) extended significantly through the use of
Sleep Mode.
Sleep mode reduces
current drain to less than 15 mA when it is engaged during periods of non-activity. Power-saving is a
default setting for the MFJ-269D
unless you defeat it when you turn on the analyzer
(instructions below).
Normally, the analyzer's processor looks for manual activation of the
Mode
switch or for any change in
Frequency
greater than 50 kHz. If neither event occurs during any given
three-minute interval
,
Sleep
mode automatically kicks in and places the analyzer in standby. A blinking
SLP
message in the display
screen lower-right corner indicates power-saving mode (see below):
To pull the unit out of
SLP
, momentarily press either the
Mode
or
Gate
button to resume operation.
To disable
Sleep
,
first
turn the unit
Off
and then
press and hold
the
Mode
button when reapplying
power. Continue holding
Mode
until after the copyright message appears on the LCD screen, then
release. If the “Power Saving” mode has been is successfully disabled, the message shown below will
appear as soon as
Mode
is released.
Sleep Mode
is a default function and will reset automatically each time the analyzer is turned OFF. To
restore
Sleep
, simply turn the analyzer
Off
and then
On
again.
3.0
MAIN MENU AND DISPLAY
WARNING: NEVER APPLY RF OR ANY OTHER EXTERNAL VOLTAGE TO THE ANTENNA PORT.
THE MFJ-269D USES ZERO BIAS DETECTOR DIODES THAT MAY BE DAMAGED BY
EXTERNAL VOLTAGES. ALSO, READ SECTION 2.0 BEFORE APPLYING POWER.
INCORRECT SUPPLY VOLTAGE OR REVERSED POLARITY CAN CAUSE DAMAGE.
3.1
General Connections
The N-female
Antenna
connector on top of the unit is the
primary RF-measurement connection
. It is
used for all functions
except
frequency counter measurements.
The
Power
connector (2.1 mm) is described in section 2.0. Please read the power-source section
carefully before attempting to operate the analyzer! Improper voltage application, the wrong battery
charger setting, or reversed polarity could permanently damage your unit.