ITTSB.EU Blog Forum
ITTSB Blog Specific => ITTSB - Small projects by Kiriakos & User reviews => Topic started by: Kiriakos GR on May 05, 2013, 08:54:07 PM
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It is very long story about writing down in detail my 12 hours adventure so to bring back in life the FLUKE 8050A which I own for two years.
Sudenly the display was refusing to stay on as usual.
The problem was that after few seconds after be powered up correctly, and display started to fade and power off.
I am a good boy and I do print all my DMM manuals especial when they have service / repair info too.
My complain about this FLUKE document is that is terribly made, regarding the PCB markings about the parts,
I got so upset about the bad schematic that I started swearing about the Americans this time.
I was in emotional pain and stress regarding rescuing for once more time this meter.
Yes in a way it is like an old lady, which has fragile health due age, but even so I do like this DMM and I was determined to fix it no matter what.
Started with recapping ( electrolytic capacitors test and exchange), I ended up to trash all the old, the fresh ones which are 30 years younger, looked as necessity.
Even so the recapping did not solve the original problem, by examining the repair manual I found one Test point which needed an Oscilloscope, so to detect a square wave at 50Hz which FLUKE call this as Display back plane drive..
I am setting the scope, and yes this damn signal was cutting off even if all the other test point regarding volts were at the expected values. ;)
Long live the GDS-2102A !!
The one thought bring the other and so I did focus my attention on the secondary PCB ( Display ).
I did re-solder all the IC, clean up contacts, and even heat up with hot air its one IC so to detect PCB cracks, or problems.
After of many hours I did manage to make it to work, but with out been able to tell which one of my actions was the most effective.
Right now I am calm again and happy, I am testing the meter for few hours and looks healthy.
But even so I will keep testing it for another 12 hours.
I got some pictures so to share, and also keep them as souvenir for my self.
By the way I did some major updates on my bench recently, those three bench-top meters are part of the new look too.
:)
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Good work! It is realy worth to fix any problem in any instrument like this, especially If you have spent many hours to get it full functional (as you get it in used condition, as i know). It requires patient and attention to prevent other damage during the repair.
Also you have my best wishes for Eastern.
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Hi George .. my best wishes for Eastern too. :)
You did touched the hot spot regarding those models, which is about spare parts availability.
Yes all my moves on this repair was slow and tremendously cautious.
The LCD is no more available, nor the major IC's of it.
Now it is working happily for 14 Hours, soon I am going to do the calibration verification and adjustments if needed, hopefully it will be 100% ready in few hours.
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One of those moments that I feel good after the battle .. ;)
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I bet that I awaked lots of memories to FLUKE :)
They told me that they had discontinued those bench type ones at 1995.