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Products => Test Equipment => Topic started by: drtaylor on November 05, 2013, 06:22:03 am

Title: Replacement LCDs for old Fluke DMMs
Post by: drtaylor on November 05, 2013, 06:22:03 am
Based on a number of comments, I'm wondering how big the market is for replacement LCDs, particularly for the 8020 (and all it's derivatives). These were and are very susceptible to polarizer failure, and conductor plating. Fluke originally partnered with Crystaloid which was founded by researchers from Kent State. They were the pioneers of LCDs. Later Fluke also bought from LXD, also in the same area. By the time the 8060 came around, the Japanese were making superior LCDs. The 8060 LCD was made by Sharp and used a separate front polarizer which lasted far longer than either of the ones supplied by Crystaloid or LXD. Anyway, LXD is still around and will do fairly small runs of LCDs, small being 500 units.

SO...that's the background. The question is, if I designed a functionally equivalent LCD for old 8020s are there enough people around to make the cost worth it? I've designed many custom LCDs over the years and I have no doubt that I could make one that everyone would be happy with. I would think I need at least 100 people interested to make it worthwhile. Maybe there's only 10 of us that care, and this whole post is folly.
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: Seg on November 05, 2013, 06:39:55 am
http://mrmodemhead.com/blog/fluke-8020a-lcd-replacement/ (http://mrmodemhead.com/blog/fluke-8020a-lcd-replacement/)

Doesn't look like the 8020 needs a custom LCD.

The 8050 tends to need replacement, but on a bench DMM I'd rather just do an LED or VFD conversion...

I've got a 27/FM which has gone a bit dim...
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: Kryoclasm on November 05, 2013, 07:41:54 am

A worthy cause indeed...

I would think that if a single batch run was done you might be able to move at least 100 in a year on ebay, but the rest would take a while to deplete.

A worthy cause, but I wouldn't sink too much cash into the endeavor if you can't take the chance of not selling the total batch.

Maybe I'm underestimating the real demand.  :-//
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: mikeselectricstuff on November 05, 2013, 08:10:22 am
I don't see why you'd bother with an ancient DMM like this - if it was something special in terms of accuracy etc. then maybe, but for an out-of-date handheld DMM I can't see that there would be that many people still using them who would spend money on a new LCD rather than treating themself to a newer unit.
 
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: kayvee on November 05, 2013, 10:41:33 am
For the same reason a market exists for vintage cars.  Maybe.

I don't recall exactly where I found the replacement LCD for my 8020A, but I do remember being surprised how easy it was to come by at the time, which IIRC was in the late 90's.

I will crack it open again and take a peek.
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: lowimpedance on November 05, 2013, 11:39:17 am
 I think most people would retire the 8020 and use its demise as a good reason to get a shiny new one as Mike said.
 Anyone interested in recovering their beloved 8020 would most likely re fit it with a modern LCD and do the mechanical mods and wiring to give them a new lease of life. Modem head has done a excellent write up on his 8020 LCD re fit.
 This is exactly what I did with my two 8020's and from the outside you would never know. And doing it this way has given me great satisfaction and appreciation for the old timers.
 As for my 8050's I was lucky enough to get Fluke replacements before they depleted their stock (in Australia at least!).
I do have an 8062a which has not fared at all well from the leaking electrolytics. Still sometimes the processor fails to initialise and the meter freezes.
 Another problem with older Fluke meters and calibrators with VFD's is they do not age well becoming almost impossible to read. I did a LED 'upgrade' to an old 8840 clunker I picked up from ebay (sold with a dud display), which turned out okay.
 I sometimes wonder why bother with the old stuff, but since I still get a kick out of tinkering with them I will plough on.


Title: Re: Replacement LCDs for old Fluke DMMs
Post by: ModemHead on November 05, 2013, 12:52:27 pm
Based on nothing more than what I read in forums and see for sale on eBay, I would be willing to bet there would be a bigger demand for 8050A displays than anything else.  'Bleeding' LCDs and dead NiCd batteries seem to be the most common failures on these old units.  Otherwise they're quite robust and useful.  At least to those of us not seduced by 'new and shiny'.  :)  The extra digit and custom annunciators make it hard to use a modern generic LCD though.
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: Excavatoree on November 05, 2013, 01:23:10 pm
First, to Dr. Taylor, thanks for the information.

I know of someone, maybe he still reads the forum, that has replaced the polarizer in the old, square, 70 series meter LCDs.  I've never done it, I got a pretty good deal on a batch of them, a long time ago.   The LCDs I have are smeared, or inoperative, I've seen one polorizer failure, but the LCD had failed in some other way as well.

I have about 5 meters that need LCDs, maybe more - I stopped repairing meters for which I don't have LCDs.  Judging from the number I see on E-bay that have failed, and the high prices I see that working LCDs can bring, I'd say it's worth studying to see if having a batch made would be viable.

Title: Re: Replacement LCDs for old Fluke DMMs
Post by: grenert on November 05, 2013, 06:28:20 pm
I would be surprised if there would be many who would invest in a new LCD for a very old 2000-count multimeter.  There may be some potential for an 8050 display, since those have more capability (20000 counts) and are readily available on ebay with bad screens for under $50.  Even then, I think I'd rather have the 8060 for not much more money (and usually available working).  I'd hate to see you stuck with a bunch of white elephant LCDs for 30-year-old meters.
Title: Re: Replacement LCDs for old Fluke DMMs
Post by: Napalm2002 on November 11, 2013, 05:47:58 am
I think that there are people who would spring for new lcds. I have quite a few meters and I would buy new lcds for all of them if the price was right. Maybe they are onto something tho. Make the 8020 lcds and make a batch for the 8050. There are people like me that love the old stuff and would hate to trash en just for a bad lcd