EEVblog Electronics Community Forum
Products => Test Equipment => Topic started by: TopGun82 on October 14, 2023, 10:07:09 am
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Hi all,
Since 4 years I have been enjoying my BM235 for some arduino/DIY projects. Since recently though my BM235 is acting up strange. VDC measurements are not showing the correct voltages anymore (way too high):
- 1.5v battery measures as 9.46v
- 3.9v source measures as 24v
- a 12v adapter measures as 76,2
- In the AutoV position, the voltages are measured correctly
- Also AC is working as expected
- I have exchanged the batteries: no change
Any idea what could cause this behaviour? And is it something I could troubleshoot/repair/reset myself?
Daniel
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What about the other DC functions, like mV and A/mA?
Take it apart and look for visible damage or PCB contamination and check selector switch contacts, etc.
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Looks like mV, A/ma is also not working. First is showing 0L, the currents are showing 0.
I opened it up, but could not see something out of the ordinary. :-\
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On this unit you will have to unsolder the input board from the main PCB in order to remove everything and access the selector switch and contacts. Also, be sure to carefully inspect all solder joints and components from different angles, maybe with a microscope. Can't tell, but is there something up with D7?
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Can't tell, but is there something up with D7?
Also D14 looks like a similar part, but one end is blackish - did the smoke get out?
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D7 does look different on my BM235 (it looks more similar to D14 with black on one end).
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Lighting can play tricks too...