MFJ MFJ-269D Instruction Manual Download Page 35 | Manualshive

Page: 35 / 37

MFJ MFJ-269D Instruction Manual Download Page 35

MFJ-269D Instruction Manual LF/HF/VHF/UHF SWR Analyzer

33

8.0

TECHNICAL ASSISTANCE

If you have any problem with this unit first check the appropriate section of this manual. If the manual
does not reference your problem or your problem is not solved by reading the manual, you may call

MFJ

Technical Service

at

662-323-0549

or the

MFJ Factory

at

662-323-5869

. You will be best helped if you

have your unit, manual and all information on your station handy so you can answer any questions the
technicians may ask.

You can also send questions by mail to MFJ Enterprises, Inc., 300 Industrial Park Road, Starkville, MS
39759; by FAX to 662-323-6551; or by e-mail to [email protected]. Send a complete
description of your problem, an explanation of exactly how you are using your unit, and a complete
description of your station.

«
...
33
34
35
36
37
»

Summary of Contents for MFJ-269D

Page 1: ......

Page 2: ...NERAL CONNECTIONS 6 3 2 POWER UP DISPLAY 7 3 3 MAIN MEASUREMENT MODES LF HF VHF 0 10 230 MHZ 7 3 4 FREQUENCY CONTROL 8 4 0 MAIN OR OPENING MODE 9 4 1 GENERAL CONNECTIONS 9 4 2 ANTENNA SWR AND IMPEDANC...

Page 3: ...NES OR BEVERAGE ANTENNAS 30 7 4 ADJUSTING TUNERS 30 7 5 ADJUSTING AMPLIFIER MATCHING NETWORKS 31 7 6 TESTING RF TRANSFORMERS 31 7 7 TESTING BALUNS 31 7 8 TESTING RF CHOKES 32 8 0 TECHNICAL ASSISTANCE...

Page 4: ...ntennas SWR impedance reactance resistance resonant frequency and bandwidth Antenna tuners SWR bandwidth frequency Amplifiers Input and output matching networks chokes suppressors traps and components...

Page 5: ...interference isn t an issue but occasionally a particularly powerful signal may be picked up by the antenna under test and routed into the analyzer bridge circuit where it conflicts with the internal...

Page 6: ...O ANY POWER SOURCE IMPROPER CONNECTIONS OR INCORRECT VOLTAGES MAY CAUSE DAMAGE TO THIS PRODUCT 2 1 External Power Supply The MFJ 1312D satisfies all external voltage and current power source requireme...

Page 7: ...are depleted charge with the analyzer power switch turned off it may take ten hours or more to fully restore depleted cells Important Warning Never change batteries with the power switch On or with a...

Page 8: ...dby A blinking SLP message in the display screen lower right corner indicates power saving mode see below To pull the unit out of SLP momentarily press either the Mode or Gate button to resume operati...

Page 9: ...wo analog panel meters also activate when the working display comes up 3 3 Main Measurement Modes LF HF VHF 0 10 230 MHz Momentarily pressing or tapping the Mode button after the first working display...

Page 10: ...F and HF bands 0 10 11 0 MHz The Upper Range switch selects 5 HF and VHF bands for 11 230 MHz coverage Note that the Upper Range switch must be set fully clockwise to the Lower Range position for the...

Page 11: ...quality parts and check them for wear oxidation dirt and tight pin contact before proceeding 2 Lead Length Make all connection electrically secure and keep all leads as short as possible This precaut...

Page 12: ...2 wavelength of cable displace the calibration plane by a controlled amount 360 degree phase rotation 2 Electrical Half Wavelengths of Cable Installing a half wavelength of cable between the load and...

Page 13: ...far end of the cable If the SWR is elevated or the Impedance Z fluctuates very much as you tune the analyzer s VFO suspect a defective cable 8 Excessive Transmission Line Loss Your cable may exhibit...

Page 14: ...ta when the measurement accuracy is questionable see examples below Reactance Sign The MFJ 269D measures the DUT s reactance X and mathematically converts it to a capacitance value Xc However the anal...

Page 15: ...r capacitive You can usually confirm the sign by adjusting the VFO If tuning down in frequency decreases reactance the reactance is likely inductive jX because inductors normally exhibit decreased rea...

Page 16: ...ng until you understand its full technical meaning Information Sources A basic understanding of transmission line and antenna behavior and terminology is very important in understanding Advanced Mode...

Page 17: ...nts with the exception of the Frequency Counter mode The Antenna connector supplies about 7 dBm output into 50 ohms 5 volts RMS and appears like a 50 ohm source resistance open circuit voltage 1 volt...

Page 18: ...ode by holding down Mode and Gate switches The opening display first indicates and then flashes to In this mode the LCD displays Frequency Impedance Magnitude Z in ohms and Phase Angle of the Impedanc...

Page 19: ...meter displays the Z in ohms while the SWR meter displays 50 ohm referenced SWR Series Equivalent Impedance display examples 7 1598 MHz 3 2 Rs 50 Xs 62 14 095 MHz 31 Rs Z 1500 sW R sW R In the left h...

Page 20: ...e meter as an analog tuning aid for identifying resonance In this mode the MFJ 269D measures and displays Frequency SWR Resistance Rs and Reactance Xs When reactance equals zero in a system that has s...

Page 21: ...might be very low due to system losses Match efficiency only applies to the loss in power transfer from a perfect 50 ohm fixed tuned source to the input of the feedline or system where the measurement...

Page 22: ...he SWR meter indicates SWR normalized to 50 Ohms and the impedance meter is disabled To use this mode connect the DUT to the Antenna connector adjust Frequency as needed and read the results on the sc...

Page 23: ...rs in other measurements Only SWR and SWR related functions are displayed for the UHF band 5 5 1 Distance to Fault DTF for HF VHF only With Vf entered in the previous function the next function in the...

Page 24: ...o enter the mode press and hold the Mode and Gate buttons until Advanced 2 appears on the screen From other Modes step through the menu holding the Mode and Gate button The first menu that appears is...

Page 25: ...s at the current frequency setting 68 511 Mhz o As you Tune the analyzer frequency the electrical length of the line will be re calculated Note that Electrical Length repeats at 360 degrees and return...

Page 26: ...rogrammed in manually If a length is not programmed in a default length of 100 feet will be selected automatically When changing UHF frequency with a 100 foot line the display rotates through 360 degr...

Page 27: ...ed length in feet of matching sections and phasing lines if you know the required variables velocity factor and electrical degrees The analyzer can also directly measure and display length using the d...

Page 28: ...it in The display will now change to Line length l 78 o Pressing Mode shifts the display to the Velocity Factor adjustment in step 2 5 6 Advanced 3 LF HF VHF only To access this mode press and hold M...

Page 29: ...cle the analyzer back to the Main or to another Advanced mode 6 0 ADJUSTING SIMPLE ANTENNAS Most antennas are adjusted by varying element length and most homemade antennas are simple verticals or dipo...

Page 30: ...o 4 Divide the measured minimum SWR frequency by the desired operating frequency 5 Multiply the present antenna length times the result from Step 4 This will approximate the antenna length you actuall...

Page 31: ...Distance to Fault mode in Advanced 2 see section 5 5 If balanced line is used operate the MFJ 269D only from internal batteries and keep it a few feet away from other conductors or earth Do not attac...

Page 32: ...round the expected value 2 Connect the transmission line or antenna directly to the MFJ 269D Antenna connector Adjust the frequency near the expected operating frequency until the lowest resistance an...

Page 33: ...r s RF matching networks The appropriate network can now be adjusted When the analyzer shows 50 ohms and a 1 1 SWR at the operating frequency with the proper amounts of capacitance to set the system Q...

Page 34: ...voltage balun is operating properly the SWR will be very low with the resistors connected from either output terminal to ground 7 8 Testing RF Chokes Large RF chokes usually have frequencies where the...

Page 35: ...62 323 0549 or the MFJ Factory at 662 323 5869 You will be best helped if you have your unit manual and all information on your station handy so you can answer any questions the technicians may ask Yo...

Page 36: ...erms are satisfied MFJ must receive the original parts you wish to replace your proof of purchase and a personal check cashiers check or money order must be provided to cover postage and handling Post...

Page 37: ......

Reviews:

No comments