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OOps, killed my LC meter

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kinarfi

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Is any one familiar enough with this to recommend fix or trash and if fix what to replace fried component with? I think I applied voltage across the the leads to kill it.
Thanks,
Jeff
 

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Can you post a schematic?
 
Is any one familiar enough with this to recommend fix or trash and if fix what to replace fried component with? I think I applied voltage across the the leads to kill it.
Thanks,
Jeff
I think I have that same LC Meter; I can look to see if there's a ref # on it.

kv
 
I'm seeing "KL4" on it; hope this helps.

kv
 
AY marking code = MMBZ5239B AY 9.1V Zener SOT23
 
it appears to be an LC100A, ebay for around $25, **broken link removed**
Maybe i'll just buy another, you usually don't get to fry a transistor like that without some colateral damage, if I do, any idea what the LCD might be worth.
 
AY marking code = MMBZ5239B AY 9.1V Zener SOT23
Thanks Tony, where did you get this information, do you have more information about the LC100A, maybe the schematic to upgrade to having the Hi C function.
 
I removed the damaged component and it seem to still be working. I also took a closer look at the damaged component and it appears to have A7 written on it instead of AY, so what does that make it?
Thanks,
Jeff
 

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I soldered leads to it and had diode type conduction between two legs(1 & 3) and one that was open, but I think I have lost it and don't remember what the polarity was. I'll see if I can find the itty bitty thing tomorrow and retest.
Just found this, easy search for SMD marking codes, https://www.sos.sk/pdf/SMD_Catalog.pdf and it says A7 is Dual Series Switching Diodes, A7 = BAV99WT1, 1 is anode, 2 is cathode, 3 is in the middle, cool I can probably find one of those.
 
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I looked on some other boards and found 2 A7W and tested them and they proved to be as described and same as an A7, so I used one to replace the one I damaged. Since the meter was working anyway, I could not see and difference, I assume the diodes had to do with protection of some sort.
This has been an education for me, hope others learned something too.
Jeff
 
So, kinarfi. Not sure what the difference is between board and yours. But, the same location as mine shows that mark on the part, if they have somehow reconfigured the circuit. I don't understand? I'll see if it's marked as a Transistor or other.

I'll look at the marking tomorrow; but this is confusing to me.

kv
 
Your KL4 is a BAT54S, My A7 is a BAV99, they both have the same configuration, your's has schottky diodes, mine has high speed switching diodes. To look up the kl4 or the A7, I would just type in "KL4 SMD Marking Code" & let google do the rest. Like I said, this has been educational for me, a week ago, I'd have been lost! Hope this helped you too.
Jeff
 
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