Yep, this seems highly likely, perhaps in tandem with sunlight damaging the adhesive layer over time and allowing air to make its way in there in the first place. As an aside, Dave says "You can design LCDs so you don't have black segments, you have a black background with a white segment or whatever". This used to be the first thing I'd do with my calculators as a kid in the 80s -- take them apart, flip the unbonded polarizing material and hey presto, black background with white letters.

@@gweilo8888 it doesn't need degraded adhesive. Just the exposed edge of the silvered layer is enough. The oxidation will creep through the material. You get similar with old photographs where the edges weren't sealed fully.

@@allensmithphotography The only reason I made that assumption is because otherwise they'd *all* be like this. I have numerous products of similar age whose LCDs haven't degraded in this manner.

@@gweilo8888 and that's very true that not every LCD of this type doesn't have this issue, just like not every mirror degrades the same way. It could have been that LCD didn't get as good of an edge seal. I know before I used photographs but mirrors do the same thing over time. And just as you mention not every mirror degrades to the same extent as every other just as the LCDs in this discussion

Yeah ha ha wish my multimeter bin was that full

I was trying to remember where I have seen it before. Gameboy.

None of the zeebra rubbish.

I remember doing that as a kid with calculator and sunglasses. The "magic" calculator.

I remember seeing videos on KZfaq about doing that to a computer monitor for maximum privacy. Basically take the polarizing filter and stick it where eyeglass lenses would go. Your monitor will then appear bright white without the glasses (and correct angle)

Sounds like a perfect magical meter for the magical audiophile industry!

Even when Dave puts it together at 9:50 it's messed up and missing at least one segment

If I don't need to replace an LCD, I leave the strips connected to the LCD. I've never had this problem with the 70 series, but the Fluke 10 series LCD contacts were fragile and were known to lift/get destroyed. Orientation is important, as the old boards had solder "blobs" of varying height and width, and they'd take a permanent "set" and not make good contact if placed incorrectly. I've been known to have to try all 8 combinations when I forgot how they went.

The only time I've had success reassembling zebra strip LCDs is if I clean all the pads and ITO display contacts with high proof iso before reassembly and make sure the bezel/housing that holds the sandwich together is as tight as I can get it. Any little bit of dust or shmoo on the contacts will leave a dead driver, and if it's not down tight there will be whole spans of dead segments.

@@treelineresearch3387 yep, 99% ipa makes zebra strips a breeze!

@@pyromen321 another vote for the IPA here, wish I'd known that as a kid messing with old digital clocks etc, could've saved lots of frustration... (take away from this, kids, turning to alcohol IS the answer sometimes)

It's kind of them to allow you to buy a replacement meter

@@Soapy555 right? Haha!

@@Soapy555 their phrasing in their email was exactly that. They’ll “let me”. Sheesh!

@@bsodmike Yeah, I assumed that's probably how they worded it RIP Fluke 89 - you will be sorely missed

Yeah, was thinking of that, and I kept a big sheet of it, but I think it got lost or tossed in the move.

@@EEVblog There is a Samsung donor LCD panel in the room of surprises though, perfect, as you have more than one chance of getting a big enough film section.

You can also use an old TV LCD that has a broken glass, it can peel off the layers of polarizing film and successfully repair a damaged polarizer, I hope you can read this Dave, greetings from Mexico.

Bromine?

That was my thinking too.

I think itd be kinda neat to print custom designs on the paper. Itd be like wallpapers. Practical no, but pretty neat

As an alternative to replacing the squished zebra strip, maybe add a bit of solder to the PCB pads (which look like they're already covered with a layer of solder, HASL finish). The addition of a thin layer of solder would change the topography to deal with the "set" and the added thickness would slightly compress the strip, mayb resulting in an improved contact.

Going to guess the analogue front end has shorted a power rail to the input, and the shorted MOV is allowing the input to be hard connected to ground, thus the low value resistor there is passing 9V to ground, and heating up. Likely the resistor was just some random one, or got the snot blown out of it, so it shorted out from burn debris to around 100R.

Was thinking the same.

D'oh

I got two of them out of my other box of multimeters!

This is exactly what we used to to back in the late 80's. Taped off the edges, and sprayed them with a few coats of aluminum paint Polarizing film on the front. These were for outdoor instruments, so we would glue ceramic heaters on the back so the display worked in the cold

I think you can replace the LCD with an LED display, if I remember correctly. There was some information about this on the internet somewhere. Damn, now that I think about it...where is my Fluke 8050. Haven't seen it since I moved! Grr!

I saw a story about a guy who removes the LCD panels from pregnancy tests. Then he makes tiny video games. He plays Doom on a pregnancy test. So you could use one of those panels for this repair, you’ll just have to squint a little.

The burn pattern suggests such, you might be correct, or maybe it was Oxygen leaking in. Awesome assessment Data!

The cheap British stuff also...

Aluminium sputtered foil on polyester sheet, the uncut edges slowly diffuse oxygen through, and create the ring of oxide as it slowly diffuses through from the cut edge.

I'd buy that. The polarizer broke cleanly at 45 degrees when he removed it.

@@martinmckee5333 I don't know how, or rather can't remember, how they are constructed, maybe has something to do maybe not. Probably that's some kind of plasticized crystal, it's not irrational to think that mechanical properties somehow match optical ones, either vertically or horizontally to the optical axis.

@@TrickyNekro it could be that or it could be a simple scribbed polarizer.

@@martinmckee5333 you mean wire grid polarizers?

You may need the plastic piece that holds the LCD in. The plastic fingers get weak, and often break off as well. I apologize, but I can't find any of the ones I have, and I can't find the part number. I'll edit this reply if I find it. EDIT: P/N is 619632 for all 87s except the IV and V. I'm not sure if this part is still available from Fluke. Even though it's not WrekDiver99's problem, other's reading this may need one. There were some e-bay sellers selling these, but it's been a while since I searched. Other possible problems are the contacts on the PCB. If they are METAL, you can clean them with an ordinary pencil eraser, then some quality contact cleaner to get the residue off. Another possibility is the front LCD surround - if it cracks like Dave's did (yes, I've cracked many as well) it won't work. I recommend visiting the EEVBLOG forum, there are people who are very good at fixing meters there who may have better/more advice.

That should have been covered under warranty.

@EEVblog...you're a funny Aussie Dave. One would think so, but Fluke stated my issue sounded like "normal wear and tear" which is "not covered under the limited warranty" It is what it is. I lost a lot of respect for Fluke when I got that note back stating it would be between $175 and $200 USD to "repair" my meter. I paid around $180 for that meter via the supplier and quantity discount (all of us jumped at the price discount we had gotten so as a whole over 50 were bought by the engineers and electricians. Back then though, that was nearly a weeks salary after taxes (I wasn't making squat as an engineer in 1991...all of $10/hr)... It is what it is...I just pop the cover and move on.

@@excavatoree So it's all intact, all of it. I will look to see if it is dirty, and I'll clean the contact points as well. The cover snaps firmly in place, and it works for a good 3 to 4 weeks, sometimes longer, sometimes shorter before I have to do it again. I might jump into the forums (I do not like forums, 17 million discussions going on at once and you can't find what you're looking for (with the search features) and then you ask the question and get jumped on by 100 people screaming "USE THE SEARCH FUNCTION IDIOT"...so...yea...not sure if I will or won't go there...LOL.

@@WreckDiver99 Are your LCD contacts (on the PCB) gold, solder, or the carbon type?