[Test-Equipment] Fluke 8050a

[Mark Richards]

I have an old Fluke 8050a bench multimeter.  It was a sweet little
instrument years ago, but the batteries have long since deteriorated.  After
replacing them - and therefore getting the unit working (what a design flaw)
- I find that the LCD display is "blotchy" - that is, characters are not
sharp and seem almost too dark.  I'm not sure it's a contrast problem but it
looks like it is.

The schematic (I don't have a service manual, just the operator's manual)
doesn't show a contrast control for the LCD.  In fact, the LCD itself isn't
really well documented.  The display drivers are old CMOS chips.  I think
"backplane" is used to adjust contrast but the schematic doesn't even show
backplane connecting.

Does anyone have a service manual out there who can give me a hint - or
maybe someone knows what the issue is.

Thanks,

/mark
K1MGY