EEVblog Electronics Community Forum
General => Buy/Sell/Wanted => Topic started by: HendoNZ on April 15, 2021, 07:27:47 pm
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Hi all,
I recently got a Fluke 8010a, but unfortunately the AC side reads overrange, no matter the input. I did some hunting around the unit and found there's a problem with the U8 board.
So now I'm on the lookout for a replacement board. So if anyone out there has a parts unit that they are will to let go of - I would be very grateful.
Cheers
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https://www.eevblog.com/forum/repair/fluke-8050a-true-rms-u32/ (https://www.eevblog.com/forum/repair/fluke-8050a-true-rms-u32/)
could be -V supply switch not powering U8
carbon composite resistors might be bad
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Thanks for the reply. U8 seems to be getting the power it needs. But it's hard to see where the problem is occurring.
Still looking for a doner board. Cheers
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AD636 or similar
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Cheers for the response. Are you suggesting that to replace the CA3046?
I think the best solution is to replace the whole board - I don't know where the issue is occurring except for it have to do with the U8 board. Cheers
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easy to test if 5 bjts in CA3046
maybe output buffer OP output blown short?
by the way made in EU AS3046
https://www.alfarzpp.lv/eng/sc/transistors.php (https://www.alfarzpp.lv/eng/sc/transistors.php)
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Thanks for the info.
I did a quick test this morning (haven't done the whole chip) but looks like pin 4 (B) is open to pin 5 (C) using a diode test and reads 1.5ohm.
Looks like I was wrong - it's designed to have a short between 5 and 4. I checked the rest of the chip and all is okay. One this I have seen - pin 22 on U8 is reading 10.6v after a zener diode of 4.3v - pin 1 on U8 gets 14v from VA then is split to pin 22.
Is that drop enough or is the zener playing up?
Cheers