W3XAF
05-25-2006, 05:35 PM
I purchased a MFJ-989D Tuner in March 2006.
It worked fine for about two weeks and then it stopped working on all bands.
I removed the tuner cover and found that the 9-volt battery installed in the battery clip had exploded and the individual battery cells were lying across both capacitors and the inductor thus shorting out these components.
I immediately removed all the individual battery cells from my tuner, cleaned up all the battery residue, cut the two battery leads at their source and reinstalled the tuner cover.
My MFJ-989D has not given me any trouble since.
The 9-volt battery is used to provide a source of DC to power the tuner’s wattmeter. #This battery is not necessary if you purchase the MFJ 1312B Power Supply for the wattmeter.
I telephoned MFJ Technical Support and informed them of the problem. #The technician on the telephone told me that he had “never heard of this problem before.” #I notified the technician that I was going to report this problem to both OSHA and the Federal Trade Commission because this problem was a safety hazard and then I ended my call.
A few days later, I received a telephone call from the MFJ Chief Engineer informing me that “it was true that this problem had occurred in the past.” #I recommended that MFJ remove the battery clip from the tuner and just instruct all users to buy the MFJ-1312B Power Supply and delete all references to the battery in the owner’s manual.
If you own an MFJ-989D Tuner, I recommend not using the 9-volt battery to power the wattmeter. #Buy the MFJ-1312B 9-Volt Power Supply and save yourselves the possibility of an explosion in your tuner.
It worked fine for about two weeks and then it stopped working on all bands.
I removed the tuner cover and found that the 9-volt battery installed in the battery clip had exploded and the individual battery cells were lying across both capacitors and the inductor thus shorting out these components.
I immediately removed all the individual battery cells from my tuner, cleaned up all the battery residue, cut the two battery leads at their source and reinstalled the tuner cover.
My MFJ-989D has not given me any trouble since.
The 9-volt battery is used to provide a source of DC to power the tuner’s wattmeter. #This battery is not necessary if you purchase the MFJ 1312B Power Supply for the wattmeter.
I telephoned MFJ Technical Support and informed them of the problem. #The technician on the telephone told me that he had “never heard of this problem before.” #I notified the technician that I was going to report this problem to both OSHA and the Federal Trade Commission because this problem was a safety hazard and then I ended my call.
A few days later, I received a telephone call from the MFJ Chief Engineer informing me that “it was true that this problem had occurred in the past.” #I recommended that MFJ remove the battery clip from the tuner and just instruct all users to buy the MFJ-1312B Power Supply and delete all references to the battery in the owner’s manual.
If you own an MFJ-989D Tuner, I recommend not using the 9-volt battery to power the wattmeter. #Buy the MFJ-1312B 9-Volt Power Supply and save yourselves the possibility of an explosion in your tuner.