MFJ-259C Instruction Manual
HF/VHF SWR Analyzer
2
1.2
Typical Uses
The MFJ-259C may be used to adjust, test, or measure the following:
Antennas:
.......................................SWR, impedance, reactance, resistance, resonant frequency, and bandwidth
Antenna tuners:
............................SWR, bandwidth, frequency
Amplifiers:
.....................................Input and output matching networks, chokes, suppressors, traps, and
components
Coaxial transmission lines:
........SWR, length, velocity factor, approximate Q and loss, resonant frequency,
and impedance
Filters:
.............................................SWR, attenuation, and frequency range
Matching or tuning stubs:
..........SWR, approximate Q, resonant frequency, bandwidth, impedance
Traps:
..............................................Resonant frequency and approximate Q
Tuned Circuits:
.............................Resonant frequency and approximate Q
Small capacitors:
..........................Value and self-resonant frequency
RF chokes and inductors:
..........Self resonant frequency, series resonance, and value
Transmitters and oscillators:
.....Frequency
The MFJ-259C measures and displays the following:
Cable length (feet)
Impedance phase (degrees)
Resonance (MHz)
Cable Loss (dB)
Inductance (uH)
Return loss (dB)
Capacitance (pF)
Reactance or X (ohms)
Signal Frequency (MHz)
Impedance or Z magnitude (ohms)
Resistance or R (ohms)
SWR (referenced to 50 ohms)
The MFJ-259C as a non-precision signal source:
VFO output is leveled at approximately 3-Vpp, or around 20 milliwatts into a 50-ohm load. This signal is
relatively pure with harmonics better than -25 dBc (dB below the fundamental-frequency carrier). The internal
source impedance (Zo) is 50 ohms.
A more complete description of the MFJ-259C's features along with proper measurement methods can be found by
reading sections covering the particular measurement you wish to make. Consult the table of contents for various
applications.
1.3
Frequency Range
The MFJ-259C covers 0.53 to 230 MHz without frequency gaps using a precision reduction-drive VFO tuning
capacitor and two band switches. Bands of coverage are:
Main Switch:
155-230 MHz 113-155 MHz 67-113 MHz
28-67 MHz
11-28 MHz
Lower Range
Lower Range Switch:
4.7-11 MHz
2.1-4.7 MHz
1.0-2.1 MHz
0.53-1.0 MHz
To select the bands above 11 MHz, turn the Main Switch to the band desired. For the bands below 11 MHz, turn
the Main Switch to Lower Range and select the desired band using the Lower Range switch.
2.0
POWER SOURCES
Please read this entire section before connecting your analyzer to any power source. Improper
connections or incorrect voltages may cause permanent damage to your analyzer!