Introduction
Congratulations on purchasing the MFJ-854 RF-Current Meter. The MFJ-854 is
designed for measuring current distribution on antenna elements and radials, and for
checking common-mode current levels on coaxial feedlines and grounds. It also works
well for tracking down RFI-causing current on household wiring and cables. Here are
some important features we think you'll like:
Wide Range:
Measures RF current from as little as 1 mA to 3 Amps in six ranges.
Full HF Coverage:
Accurate from 1 MHz to 30 MHz and beyond.
Low Interaction:
Sense coil has minimal effect on circuits under test.
Large Cable Capacity:
Accepts cables up to approximately 1/2" in diameter.
Accurate:
Diode-compensated Op-Amp delivers improved meter linearity.
Rugged:
Built to last with a sturdy all-aluminum case and G-10 pc board.
Battery Saver:
Press-to-test power circuit turns unit off automatically after 15 seconds.
Long Battery Life:
Meter draws 3-mA, battery's service life approaches shelf life.
Handheld Size:
Weighs 11 ounces, only 2.3" x 1.6" x 6.5" (including sense coil).
Controls and Locations
Sensitivity
Power
On
<30mA
Adj
30mA
100mA 300mA
1A
3A
Ampres
2
3
4
5
MFJ-854
Cable
1
6
9-V
1. Sense Coil:
Clamps onto conductor under test, accepts diameters to around 1/2" .
2. Meter:
Calibrated scale indicates readings in mA or Amps.
3. Range:
Selects from six measurement ranges.
4. Sensitivity:
Works on <30 mA range, adjusts gain for low-level measurements.
5. Power On:
Momentary switch applies power, activates 15-second power-off delay.
6. Battery Clip:
Accepts any standard 9-V
flat-pack battery.
Summary of Contents for MFJ-854
Page 5: ...Schematic Parts List ...
