MFJ-989D VersaTuner V
Instruction Manual
4
MFJ-989D Specifications
Power Rating:
1500-Watts, SSB/CW
Matching Range:
6.5-3200 Ohms at 1500 Watts input
Configuration:
T-Network with rotary inductor
Meter Range:
300 and 3-kW forward, 60 and 600-W reflected
Meter Detection:
Averaged and instantaneous-peak, active-circuit detection
Dummy Load:
50-Ohms non-inductive, 300-W, convection cooled
Antenna Selector:
6-position multi-section heavy-duty ceramic
Balun:
Guanella-style 1:1 current, dual-core 2.4-inch toroid form
External Power
12-vdc, 2.1mm rear-panel jack or internal 9-Volt battery (see text).
Dimensions:
12-7/8" W x 6" High x 11-5/8" D (32.7 x 15.2 x 29.5 cm)
Weight:
9 pounds (4.08 kG)
Power Requirement
The upgraded MFJ-989D requires a power source to run its
SWR/Wattmeter
circuitry. Power may come
from one of two sources:
1.) 9-Volt Battery:
To install a 9-volt battery, access the internal holder and snap clip by removing the
12 cabinet screws and lifting off the tuner cover. The holder is mounted on the upper right corner of the
front panel.
We strongly recommend installing a battery, even if you intend to use an external power
source
. Doing so provides backup voltage to operate the meter and also prevents the battery snap clip
from floating loose inside the cabinet where it could contact high RF potentials. If you elect to omit the
battery, make sure the snap clip is anchored solidly to the battery holder where it was wedged for
shipping.
To extend battery life, the tuner has built-in
RF-sensing
that applies power to the meter electronics only
when a transmit signal is applied. After a short period of transmitter inactivity, power is removed
automatically.
Important Note: The 9-V battery powers only the meter electronics. It does not power the meter LEDs.
You must supply external DC to illuminate the SWR meter.
2.) 12-VDC External Power:
The
Meter Lamp
power jack is located above the
Transmitter
connector
on the rear panel. Apply power from any filtered dc wall adapter (MFJ-1312D or equivalent), or use
your station's 13.8-Vdc supply. A cord fitted with a 2.1-mm plug is supplied with the tuner for this
purpose. If you make your own supply cord, connect
+12 volts to the center pin and ground the outer
sleeve
, as shown below:
