Electronics > Repair

Ongoing Fluke 175 Repair - making progress

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MC2Short:
Hey guys so a while back I posted about my fluke 175. I accidentally cooked it with a MOT like an idiot. (Yes, I discharged the cap and all.)
So at first I wasn't getting any kind of ac voltage readings, and in continuity it just kept beeping with the leads not even connected. I was told to try desoldering 6 SOT23 chips and trying it again. Pictures included here.. So I desoldered them, and then nothing worked. I was then told I probably shouldn't have desoldered the top two. After lots of trying to figure out what those top two SOT23's were, I got some new ones from digikey and soldered those on. Now, it works, kind of. When I measure AC it measures as accurately as I'd need it to, and with DC it also measures right where it pretty much should. Now in ohms mode it also seems good.in continuity mode it seems like it takes its time, but shorting the leads beings the ohms reading down a little slowly and then beeps. If I hold it it'll go - numbers on me. Now the part I don't really understand is I have a brand new 9v battery in there, and when I turn the meter off, after a sec it will display batt on the screen. Once it does that I can move the switch anywhere I want and it will just say batt until I disconnect it. So, after that long rambling post my question is does anyone know why or what to check? And also the 4 other SOT23s just above the bridge I still haven't replaced. They are all marked 6B> I was told they were MMBF5484's. Then another person on here said they were BC817-25's and I think that's correct. What exactly do these 4 SOT23's do, and would they have any effect on the batt coming on when the meter is off? I wouldn't think so but... Hey I really have no idea. Thanks for your help. First picture are the SOT23s I removed. I replaced the top two, then the 6b> ones I still haven't replaced. The rest of it is pretty self explanatory. Thanks again.

MC2Short:
If anyone needs more pictures or anything just let me know I got a bunch.

MC2Short:
I soldered on the other SOT23s I thought might of been the wrong ones, and it's working now!

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