MFJ IntelliTuner -991, Instruction Manual

Page 1: ...ns Before Operating Equipment MFJ ENTERPRISES INC 300 Industrial Park Road Starkville MS 39759 USA Tel 662 323 5869 Fax 662 323 6551 COPYRIGHT 2004 MFJ ENTERPRISES INC C Models MFJ 991 and MFJ 994 VERSION 1A IntelliTuner Automatic Antenna Tuners TM ...

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Page 3: ...N Buttons 4 L UP and L DN Buttons 4 AUTO Button 4 TUNE Button 5 POWER Button 5 Back Panel 6 Power 6 Remote Port 6 Radio Interface 6 Transmitter 7 Ground 7 Wire 7 Antenna 7 Installation 8 SWR Wattmeter 8 SETUP Target SWR 9 Auto Tune SWR 9 Meter Range 10 OPERATION Manual Tuning 10 Component Limit 11 Antenna Memory 11 Tuner Status Indicators 12 Grounding Hints 13 Antenna System Hints 13 Location 13 M...

Page 4: ...ibration 19 Frequency Counter Calibration 20 In Case of Difficulty 20 Technical Assistance 21 List of Accessories 21 Circuit Block Diagram 22 FIGURES Figure 1 Installation Block Diagram 3 Figure 2 Front Panel 4 Figure 3 Button Action 5 Figure 4 Back Panel 6 Figure 5 Alinco Interface Cable 7 Figure 6 Icom Interface Cable 7 Figure 7 SWR Wattmeter 8 Figure 8 Power On Operations 15 Figure 9 Circuit Bl...

Page 5: ...s and tuner settings When you key your transmitter MFJ s InstantRecallTM checks its memory to see if you have operated that frequency before If so tuning is instantaneous and you re ready to operate If not MFJ s IntelliTuneTM algorithm based on MFJ s famous SWR Analyzer technology kicks in It measures the complex impedance of your antenna Next it calculates the components it needs and instantly sn...

Page 6: ...ange 6 to 3200 ohms MFJ 991 12 to 800 ohms MFJ 994 Minimum power for tuning 5 watts MFJ 991 10 watts MFJ 994 Maximum power while tuning 100 watts with foldback 20 watts without foldback RF power limit 150 watts PEP SSB 100 watts CW MFJ 991 600 watts PEP SSB 300 watts CW MFJ 994 Frequency range 1 8 to 30 MHz continuous coverage Frequency counter accuracy 1 kHz across HF bands Frequency counter rang...

Page 7: ...nna to the ANTENNA connector using a 50 ohm coaxial cable or connect your random wire to the WIRE binding post 4 Press the POWER button to turn on the tuner Lock the AUTO button in to select semi automatic mode 5 Key your transmitter to output a carrier of 10 watts CW FM or AM 6 Press the TUNE button briefly to start the automatic tuning process When completed check to ensure an SWR of 2 0 or less...

Page 8: ...nents Note Pressing C UP and C DN simultaneously toggles the capacitor between the input and output sides of the L network Forward needle bounces to 30 watts when the capacitor is on the transmitter side Reflected needle bounces to 5 watts when the capacitor is on the antenna side L UP and L DN Buttons Used to manually increase or decrease the inductance of the L network matching circuit The induc...

Page 9: ...icate a model 994 When the power is off the tuner is placed in bypass mode straight through from TRANSMITTER to ANTENNA and WIRE When power is turned on the tuner automatically restores all previous settings WARNING Do not turn the power on and off rapidly otherwise the tuning setting memory can be corrupted and the unit will have to be reset to factory defaults BUTTON ACTION TUNE C UP L UP TUNE T...

Page 10: ...the remote control The red Tuning LED lights to indicate tuning is in progress and the green SWR LED lights when the SWR is below the target SWR Note To use the remote control the AUTO button on the automatic tuner must be locked in otherwise Automatic mode is selected Radio Interface A 3 5 mm stereo phone jack for connecting to the tuner interface connector of compatible radios The tuner should b...

Page 11: ...8 IC 746 IC 756 IC 765 IC 775 and any Icom radio that supports the Icom AH 3 and AH 4 tuners Pin 1 Key connects to the Tip of 3 5 mm Stereo Phone Plug Pin 2 Start connects to the Ring of 3 5 mm Stereo Phone Plug Pin 3 13 8V connects to the Center Pin of Power Plug Pin 4 Ground connects to the Sleeves of both 3 5 mm Stereo Phone Plug and Power Plug Figure 6 Icom Interface Cable Transmitter SO 239 c...

Page 12: ...ge 3 3 Connect the antenna to the tuner as follows Coaxial feedline to the SO 239 connector labeled ANTENNA or Random wire or single wire line antennas should be connected to the WIRE binding post on the back of the tuner Note the back panel warning Do not connect WIRE and ANTENNA at same time Note Route all single and random wire antennas safely to prevent RF burn hazard 4 A GROUND post is provid...

Page 13: ...s and behaves In addition to displaying power and SWR the meter also indicates tuner status when you make setup changes The meter needles bounce or rise to one point and stay to provide information In this mode the meters do not indicate power levels For example when you press C DN and L DN simultaneously to place the tuner in bypass mode the reflected needle bounces to the 20 watts mark until you...

Page 14: ... more or less capacitance or inductance is needed manual tuning must be by trial and error Press C UP one time and the reflected power will indicate if C UP was the right direction If it was press C UP again and observe reflected power If not press C DN twice once to return to the original setting of C and once for one click past it Manual tuning of inductance is similarly accomplished using L UP ...

Page 15: ...setting for any frequency from 7047 to 7053 kHz The memory resolutons for the HF amateur bands 160 through 10 meters are Meter Frequency Range kHz Memory Resolution kHz 160 1800 2000 2 75 80 3500 4000 4 60 5330 5 5346 5 5366 5 5371 5 and 5403 5 two memory locations 40 7000 7300 7 30 10100 10150 10 20 14000 14350 14 17 18068 18168 18 15 21000 21450 21 12 24890 24990 25 10 28000 29700 28 Table 1 Ant...

Page 16: ...Status Button Action Meter Needles Stationary Needle Reads Meter Range 30 watts TUNE L DN 30 W Forward Meter Range 300 watts TUNE L DN 300 W Forward Auto Range OFF Sticky Tune OFF Auto Tune SWR 0 5 TUNE C DN TUNE 2 seconds TUNE L UP 5 W Reflected Auto Tune SWR 1 0 TUNE L UP 20 W Reflected Auto Range ON Sticky Tune ON Auto Tune SWR 1 5 TUNE C DN TUNE 2 seconds TUNE L UP 60 W Reflected Both Needles ...

Page 17: ...dequate for RF grounding because they are single conductors Ground rods by themselves are almost useless for dependable RF grounding RF grounds work much better when spread out over a large area especially when they employ multiple connections directly to the equipment ground point Metal water pipes heating ducts and fences may work especially if they are connected together with multiple wires but...

Page 18: ...uce the difficulty in matching an antenna with a tuner Never center feed a half wave multi band antenna with a high impedance feedline that is close to an odd multiple of a quarter wave long Never center feed a full wave antenna with a feedline close to a multiple of a half wave long If this tuner will not tune a multi band antenna add or subtract 1 8 wave of feedline for the band that won t tune ...

Page 19: ...er On Operations Firmware Version Number Make sure the meter is calibrated To obtain the firmware version number press and hold the C UP button while turning the power on The version number X XY is represented by the meter forward needle for X X and the reflected needle for Y For example forward needle on 10 watts mark and reflected needle on 2 watts mark represent firmware version number 1 02 Rel...

Page 20: ...ove Remember that all antenna memories will be lost and tuner setting will return to default Self Test A self test routine checks the functions of the tuner This routine checks the meter the front panel buttons and the internal memory During the self test you may stop the test by turning off the unit however this should NOT be done during the memory test or the memory could be corrupted The self t...

Page 21: ...E FAIL 15 TUNE button is shorted or improperly connected MEMORY FAIL 20 Non volatile memory circuitry is improperly connected WAKEUP FAIL 30 Microprocessor wakeup circuitry problem PD FAIL 40 Power down circuitry problem Table 3 Failure Messages Power Down Circuit Test When the 12 VDC power to the tuner is turned off the tuner saves all settings to non volatile memory The Power Down Circuit Test c...

Page 22: ...pressing the L UP button in the first group and the last button L DN in the last group will not produce a click Wattmeter Calibration To calibrate the wattmeter you will need a Phillips screwdriver and a tuning tool or small flat blade screwdriver WARNING Never operate the MFJ 991 4 with its cover removed dangerous voltages and currents can be present during operation Never exceed tuner specificat...

Page 23: ...in the middle of an HF band such as 7 253 MHz for calibration 5 Press and hold both the TUNE and L UP buttons while turning the tuner power on Both meter needles will bounce Release the buttons 6 Key the transmitter to output 100 watts and adjust the trimmer capacitor C91 for minimum reflected power Notice the reflected meter movement is exaggerated for easier calibration 7 Key the transmitter to ...

Page 24: ...etween the two big integrated circuits until the tuner s meter needles settle at the 0 watt marks Notice the meter movement is exaggerated for easier calibration Nominal tolerance of the frequency counter is 1 kHz 7 Turn off the power to the tuner and the transmitter 8 Secure the cover back onto the tuner In Case of Difficulty If the tuner acts erratic reset the tuner to factory defaults by pressi...

Page 25: ...Enterprises Inc 300 Industrial Park Road Starkville MS 39759 by facsimile FAX to 662 323 6551 or by email to techinfo mfjenterprises com Send a complete description of your problem an explanation of exactly how you are using your unit and a complete description of your station List of Accessories MFJ 993RC Remote control MFJ 1316 12 VDC 1 5 amp power supply MFJ 5124A Interface cable for compatible...

Page 26: ...91 994 Circuit Block Diagram Transmitter Antenna Remote Port Radio Interface Wire Impedance Sensor SWR Sensor Frequency Counter Memory Microcontroller Relay Drivers Ground Inductors 0 xx uH Capacitors 0 xxxx pF SWR Wattmeter Push Buttons User Interface Z MFJ 991 0 3900 pF 0 24 uH MFJ 994 0 2950 pF 0 17 uH L Network ...

Page 27: ...rvice Department at 662 323 0549 or the MFJ Factory at 662 323 5869 4 This warranty does not apply to kits sold by or manufactured by MFJ Enterprises Inc 5 Wired and tested PC board products are covered by this warranty provided only the wired and tested PC board product is returned Wired and tested PC boards installed in the owner s cabinet or connected to switches jacks or cables etc sent to MFJ...

Page 28: ...MFJ 991 994 Manual Version 1A Printed In U S A 01 04 300 Industrial Park Road Starkville MS 39759 MFJ ENTERPRISES INC ...