MFJ Enterprises MFJ-249B User Manual

TABLE OF CONTENTS
MFJ-249B HF/VHF SWR Analyzer ............................................................................................ 2
Introduction .................................................................................................................................. 2
Powering The MFJ-249B ............................................................................................................. 3
Battery Installation ....................................................................................................................... 3
Alkaline Batteries ............................................................................................................ 3
NiCd Batteries ................................................................................................................. 4
Power Saving Mode......................................................................................................... 4
Operation Of The MFJ-249B .......................................................................................................5
SWR mode....................................................................................................................... 5
Magnitude of the Impedance Mode................................................................................. 6
Frequency Counter Mode ................................................................................................ 6
Gate time selection .......................................................................................................... 6
Adjusting Simple Antennas.......................................................................................................... 7
Dipoles............................................................................................................................. 7
Verticals........................................................................................................................... 7
Tuning an Antenna .......................................................................................................... 7
Measuring the Feedpoint Resistance of Antennas .......................................................... 8
Testing and Tuning Stubs and Transmission Lines...................................................................... 8
Velocity Factor of Transmission Lines ........................................................................... 9
Impedance of Transmission Lines................................................................................... 9
Adjusting Tuners .........................................................................................................................10
Adjusting Amplifier Matching Networks....................................................................................10
Testing RF Transformers.............................................................................................................10
Testing Baluns ................................................................................................................11
Measuring Inductance and Capacitance ......................................................................................11
Measure Capacitance......................................................................................................12
Measure Inductance........................................................................................................12
Resonant Frequency of tuned circuits .........................................................................................12
Testing RF Chokes .........................................................................................................13
Technical Assistance ...................................................................................................................13

MFJ Enterprises MFJ-249B Specifications

General

Brand	MFJ Enterprises
Model	MFJ-249B
Category	Measuring Instruments
Language	English

Summary

INTRODUCTION

POWERING THE MFJ-249B

BATTERY INSTALLATION

Alkaline Batteries

Instructions for installing and configuring alkaline batteries for the MFJ-249B analyzer.

NiCd Batteries

Instructions for installing and configuring NiCd batteries and the internal charger for the MFJ-249B.

Power Saving Mode

OPERATION OF THE MFJ-249B

SWR Mode

Explanation and use of the SWR measurement mode for the MFJ-249B analyzer.

Magnitude of Impedance Mode

How to measure the magnitude of impedance of loads connected to the analyzer.

Frequency Counter Mode

Instructions for using the MFJ-249B as an accurate frequency counter.

Gate Time Selection

Options and selection method for gate time in frequency counter mode.

ADJUSTING SIMPLE ANTENNAS

Dipoles

Guidance on adjusting dipole antennas, focusing on element length and resonance.

Verticals

Guidance on adjusting vertical antennas, including radial systems and element length.

Tuning an Antenna

Step-by-step procedure for tuning basic antennas using the MFJ-249B analyzer.

Measuring the Feedpoint Resistance of Antennas

TESTING AND TUNING STUBS AND TRANSMISSION LINES

Velocity Factor of Transmission Lines

Impedance of Transmission Lines

ADJUSTING TUNERS

ADJUSTING AMPLIFIER MATCHING NETWORKS

TESTING RF TRANSFORMERS

Testing Baluns

MEASURING INDUCTANCE AND CAPACITANCE

Measure Capacitance

Procedure to measure unknown capacitance using standard inductors and the analyzer.

Measure Inductance

Procedure to measure unknown inductance using standard capacitors and the analyzer.

RESONANT FREQUENCY OF TUNED CIRCUITS

Testing RF Chokes

TECHNICAL ASSISTANCE