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Have you opened the meter up to inspect the PCB and components?
Do you know which microcontroller is used for that meter?
It may help you in finding a datasheet/schematic to fault find.
Yes, the LL4148 is the surface mount version of the 1N4148. I selected it as it looked similar to the shorted one.
Should I be using a general purpose diode such as a BAV100 instead?
Thanks Nigel, that makes sense. Yes removing the shorted diode has made the meter work again :)
I was thinking of replacing it with an LL4148 which looks like the same form factor. How does it defer from a standard SOD-523F-2 package diode?
Hello,
I have a fairly old multimeter that has a shorted diode near the battery input? Attached is a photo of the diode on the PCB.
What is the purpose of this diode (back EMF?) and what would have caused it to short out?
There are a couple of other similar looking orange diodes on the PCB...
When removed from the boards, almost all 20 of the capacitors measured out of spec between no reading to typically 80-140µF.
Attached is a photo showing the burnt PCB leaded fuse. Looking at photos of other inverter boards for sale, it seems to be a F10A. Is anyone able to confirm from the...
Going to desolder them and check. Can't measure them properly in-circuit. It's for a backlight inverter board where the fuse has blown. Lots of darkening on the PCB.
Hello,
I am looking for these capacitors which are leaded and measure approx. 7mm height x 8.5mm diameter.
What type of capacitor should I be searching for? They look different to standard electrolytic capacitors.
Thanks.
That's not a bad job. You may find it harder to solder smaller components. There still appears to be some sticky residue next to R2.
How secure is the tape? You may want to add a drop of superglue at points where you won't be soldering.
If the top of R2 goes to the bottom-right leg of Q1...
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