EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: belzrebuth on May 29, 2018, 01:45:18 pm
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I can't find any info about it on the net.
The multimeter turns on and seems to recognize the different ranges when I turn the selector in but I get no readings..
No resistance readings, no voltage reading, no continuity...the only thing that seems to work is the current measurement and only on the unfused 20A terminal..I've tested only up to 1A and the meter seems to track the current.
It's pretty clean inside no dust, corrosion or battery leak of any sort..
Also, the 360mA fuse is replaced with a 3A.
I've already cleaned the pcb tracks of the mode selector.
Where should I start troubleshooting this?
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I probably did something wong when uploading those images...
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I would check for first if there is somewhere some shorted componenet.
Then I would check every ic for some problems.
After all this I would start to check if the values of the componenets are in good range...
Sent from my GT-I8260 using Tapatalk
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I'd start getting the rotary switch off, checking the state of contacts under there and cleaning them. (Also make sure the contacts are all there and in the right positions.)
Then the state of the trimpot (does it still have a track and brush after all the bashing it has taken?), then figure if that BD435 is there to regulate anything, then find the datasheet for whatever hides under the LCD. (Intersil ICL something?)
By then you should be well on the way.
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seems to be based on ICL7106 ICL7107 chips ?? you can find schematics who could help
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To start with I would take another multimeter and confirm approximately 10 to 11 megohms input resistance from the test leads through the Philip's input jacks.