An update for this thread:
For anyone looking for a quick turnaround on fully assembled Fluke display assemblies (#728873),
I now have them available using our new assemble PCB and the AHOL blue LED module. I am one of AHOLs
biggest customers, and no display repair on the Fluke 8840A/42A would be possible with out his development effort.
I have customers who just can't do the de-solder/solder rework reliably. I started by pre-wiring AHOLs modules.
But I always wanted a mechanical-only replacement. So I bit the bullet and re-engineered the Fluke display PCB
to work with both the AHOL blue LED module and our graphic OLED mono-color programmable display module.
Our module cannot compete with the AHOL display. But I hope that, with several avenues of repair, many more Fluke
8840A & 8842A meters will be saved from the scrap heap!
The Fluke disassembly procedure should be followed. Dont try to shortcut.
Disconnect everything from the front panel including 2 16 pin ribbon cables.
Remove power bottom switch arms and F/R sw arm and cal sw arm.
Remove bottom shield.
Remove 4 front panel screws.
Release ALL 6 main PCB rivets without breaking them.
Release main PCB below frame about 1.5".
Remove face plate.
release 2 plastic clip retainers from metal frame.
Remove display assy from frame. This is challenging.
Insert new assy as old one came out. The fit is tight, but it will go in!
Once in place, reverse everything and inspect before hooking up 5V display power!
You did unplug the meter from the mains....
You did use a static guard on your wrist...
I have included a few pictures and links.
eBay
https://www.ebay.com/str/hollywoodcontrols/Suplus-Equipment/_i.html?store_cat=985206012website
https://www.hollywoodcontrols.com/phpFluke/Fluke_LED_Display.phpkjo KO3Y