MFJ-941EK Tuner Kit
Instruction Manual
- 22 -
TESTING
[ ] Select
Bypass, Dummy Load.
Check
Dummy Load connector
.
[ ] Select
Bypass, Bal Line Wire.
Check
Wire
binding post.
[ ] Select
Bypass Coax-1
. Check
Coax-1
connector.
[ ] Select
Bypass Coax-2.
Check
Coax-2
connector.
Now, check
Tune
mode for continuity. Move the common VOM lead from the
Transmitter
connector to the stator of the
Antenna
capacitor and repeat the test
procedure.
[ ]
Tuned,
Dummy Load
[ ]
Tuned,
Bal Line Wire
[ ]
Tuned,
Coax-1
[ ]
Tuned,
Coax-2
4:1 Balun DC Check:
[ ] Connect VOM leads across the
Balanced Line
terminals and confirm
continuity.
Power Meter Calibration:
The accuracy of your MFJ-941E SWR/wattmeter depends on the reference
standard you use for calibration. A Bird through-line wattmeter with a 100H slug
(100-W) is probably the best choice. A high-quality digital meter with certified
accuracy will also work well. Avoid using low-cost references with unknown
specifications. Also, your 50-Ohm dummy load should be capable of handling
100W without overheating and changing value.
To avoid abrupt full-scale meter excursions, pre-set the meter calibration trimpots
to the approximate settings shown below in Diagram 14:
R5
R6
R7
R8
30W FWD
300W FWD
30W REV
6W REV
Diagram 14: Trimpot adjustments
