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MFJ Giant automatic SWR/Wattmeter Model MFJ-869 INSTRUCTION MANUAL CAUTION: Read All Instructions Before Operating Equipment MFJ ENTERPRISES, INC. 300 Industrial Park Road Starkville, MS 39759 USA Tel: 662-323-5869 Fax: 662-323-6551 COPYRIGHT 2009-2010 MFJ ENTERPRISES, INC. VERSION 2B...
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Customers using this manual should report errors or omissions, recommendations for improvements, or other comments to MFJ Enterprises, 300 Industrial Park Road, Starkville, MS 39759. Phone: (662) 323-5869; FAX: (662) 323-6551. Business hours:...
There is also a relay connector with normally open and normally closed connections that toggle when the SWR is above the same pre-set limit. The MFJ-869 enters a “sleep” mode when idle and when no transmit signal is present, turning off the microprocessor clock to avoid the generation of spurious signals.
MFJ-869 AMP ENABLE IN/OUT connectors. A normally closed high-speed reed relay interrupts the amplifier enable signal when a user high-SWR pre-set is exceeded. A normally closed relay is used so that your amplifier system works properly when the MFJ-869 is turned off.
MFJ-869 MFJ Giant automatic SWR/Wattmeter Instruction Manual Front Panel automatic MFJ GIANT SWR / WATTMETER MODEL MFJ-869 POWER SWR FWD 200 2K PEAK ALRM MODE PEAK ALARM POWER Figure 1. MFJ-869 Front Panel. • SWR/Wattmeter: The single-needle meter measures SWR, forward and reflected power. It operates whenever the unit is powered on.
MFJ-869 MFJ Giant automatic SWR/Wattmeter Instruction Manual Press both [MODE] and [PEAK] buttons simultaneously to show the current power meter range setting, and then hold or press again within half a second to cycle the meter range setting. Default is Auto Ranging.
MFJ-869 MFJ Giant automatic SWR/Wattmeter Instruction Manual • ALARM Button: Used to toggle the alarm feature on and off and to set the alarm SWR from 1.5 to 3.0. When enabled, the ALRM LED will light and the buzzer will sound when the SWR is above the alarm SWR.
The unit requires 12 volts DC at up to 350 milliamps. The use of a regulated supply is not mandatory but is recommended for best performance. An optional 12 volts DC 500 milliamp power supply, the MFJ-1312D, is available from MFJ Enterprises, Inc. WARNING: Do not apply voltages greater than 18 volts to this unit, or permanent damage to the unit may result.
MFJ-869 MFJ Giant automatic SWR/Wattmeter Instruction Manual • RS-232: DB-9 female connector for connecting to the computer’s RS-232 serial port to update firmware. Check http://www.mfjenterprises.com/support.php for the latest version of the firmware. • RLY: 3.5 mm stereo phone jack connected to a high-speed reed relay switch with the tip normally closed (NC), the ring normally open (NO), and the sleeve as common (COM).
Self Test A self-test routine will check the functions of the MFJ-869. This routine checks the analog meter, the front-panel buttons, the internal memory, the audio circuitry, and the power-down circuitry. 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.
MFJ-869 MFJ Giant automatic SWR/Wattmeter Instruction Manual 6. If the unit is okay, the ALRM LED will turn on steady and a message PASS will send repetitively as Morse code (di-dah-dah-dit di-dah di-di-dit di-di-dit). If there is a problem, the ALRM LED will blink continuously, a mode LED will turn on steady and a failure message will send repetitively.
WARNING: Do not touch anything inside the wattmeter during operation! Serious, painful RF burns can result. WARNING: Never operate the MFJ-869 with its cover removed; dangerous voltages and currents can be present during operation. Never exceed wattmeter specifications. 1. Make sure the analog meter is calibrated. See “Wattmeter Calibration” section for the calibration procedure.
WARNING: Do not touch anything inside the wattmeter during operation! Serious, painful RF burns can result. WARNING: Never operate the MFJ-869 with its cover removed; dangerous voltages and currents can be present during operation. Never exceed wattmeter specifications. 1. Turn off the power to the unit and the transmitter.
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.
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MFJ Enterprises, Inc. warrants to the original owner of this product, if manufactured by MFJ Enterprises, Inc. and purchased from an authorized dealer or directly from MFJ Enterprises, Inc. to be free from defects in material and workmanship for a period of 12 months from date of purchase provided the following terms of this warranty are satisfied.
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MFJ ENTERPRISES, INC. MFJ-869 Manual 300 Industrial Park Road Version 2B Starkville, MS 39759 Printed In U.S.A. 01/2010...
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