Fluke 179 won't tun on

[stj]

Re: Fluke 179 won't tun on

white ceramic board on the right about halfway up needs resoldering

[tibimakai]

Re: Fluke 179 won't tun on

I'm not sure, which one you are referring too.

[stj]

Re: Fluke 179 won't tun on

forget the brown for now.
btw, on looking at the second image - broken solder joints on the vertical ceramic board where it's soldered to the main board.

[tibimakai]

Re: Fluke 179 won't tun on

Do you mean the brown color?

[stj]

Re: Fluke 179 won't tun on

look at the earthing ring around the central screw hole - it shows the same difference.

nice foto - check the crystal and check for power across the tantalum smoothing caps.

[tibimakai]

Re: Fluke 179 won't tun on

Buzzer is missing from the back cover.
Here are the pictures, taken with my phone.
Hopefully, they are clean enough. If they are not adequate, I will take new ones with my camera.
I will recheck those JC diodes.
Actually, the trace and via is not missing from the LED, it is missing from a resistor, next to the Texas Instruments IC(left upper corner).

[tibimakai]

Re: Fluke 179 won't tun on

I know, that it's not easy to diagnose something, from the distance.
I will take some pictures, when I get home.
Those pads may be oxidized, but mine are not even there.
I have to check, if the buzzer is actually there, I don't remember.

[retiredcaps]

Re: Fluke 179 won't tun on

There are at least 3 internal revisions of the 179. Each have significant changes.

Trying to remote troubleshoot using other people's pictures is like asking a surgeon to operate on you using your brother's x-rays. Post clear focused pictures of your own 179 (both sides) with the lcd removed.

There are no schematics of the 179 publicly available. I suggest you see if the oscillator/clock is running as a start.

[stj]

Re: Fluke 179 won't tun on

your comparison photo's:
left image is gold plated, right photo is oxidised copper - both have pads.

got a complete parts side foto?

[tibimakai]

Re: Fluke 179 won't tun on

I may have found the JC component, it seems like it's a fast switching diode, that looks like a transistor. SOT323, pin #1 not connected. BAL74W.

[tibimakai]

I have picked up this meter, in decent condition for $20.
It seems like, it is completely dead.
Fuses and battery are good.
After opening, I have found some transistors looking components that are shorted, but not completely. At one of them, it seems like the green paint came off at one leg and in the same spot, seems like the trace has a damage as well(maybe missing transistor leg, hard to tell).
I'm not sure what they are actually to properly test them.
They have a JC marking on them, thy could be some kind of diodes?
I can't find schematic for this meter anywhere.
I have also noticed, that the two PCB trace circles(buzzer contacts) are missing, even the traces leading to these two pads are not reaching the circles.
Another thing that I have noticed, that one of the traces that goes through a via to one of the LCD LEDs is missing. Between resistor and LED.
What could have happened here?
I have not taken any pictures yet, but I have found some picture at the eevblog.