MFJ MFJ-802 User Manual

MFJ-802B Instruction Manual

INTRODUCTION

Thank you for purchasing the MFJ-802B. A field-strength meter (or
FSM) is one of the most practical pieces of ham test equipment you
can own, and the MFJ-802B has some special features we think you'll
like. For example, it has a huge high-resolution meter with a robust 0­100 scale that's easy to read from several feet away. It also combines a
balanced pick-up antenna with a RF-insulated enclosure to eliminate
hand-capacitance errors typical of older-style meters. There's a high-Z
balanced decoupling network that ensures top efficiency over a wide
frequency range and provides complete isolation between the detector
and metering circuits. And, there's a uA-type meter movement with a
wide-range sensitivity control to handle signals from the milliwatt to
kilowatt level. Add the MFJ-802R remote pickup, and you can
monitor field strength from anywhere you wish in the comfort of your
shack. Inexpensive low-voltage dc wire connect the two units together.
Like most field-strength meters, the MFJ-802B is extremely simple to
operate. However, as with any piece of RF test equipment, it has
limitations you should know about--and we urge you to read the
manual carefully before using it.

YOUR METER'S CONTROLS

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MFJ-802B Instruction Manual

2. Easy-to-Read Meter Scale: Bold 0-100 scale is readable for

several feet--may be set up at any convenient location near your
operating site. High-quality meter movement resolves even small
changes in the RF field.

3. Remote Detector Jack: Standard phone jack accepts monaural

1/4" plug when MFJ-802R remote detector is used.

4. Wide-Range Sensitivity Control: Adjusts your meter for a wide

range of power levels and distances to the RF source. To prevent
damage, always begin measurements with the sensitivity control set
at minimum (fully counter clockwise).

USING YOUR METER

The MFJ-802B is useful anywhere a hand-held or stationary field­strength meter is needed. For example, it's perfect for resonating
critical HF mobile antennas, adjusting tuning networks, optimizing
antenna arrays for highest ERP, and tuning transmitter circuitry for
maximum o utput. Rememb er to exercise caution when working near
transmitting antennas.

Important Safety Warning: Never work in close proximity with any
energized transmit antenna. Even at low power, antennas may
develop dangerous RF-voltage levels that can cause painful burns
and permanent injury.