EEVblog 1641 - Can I Resurrect My First Digital Multimeter?

[EEVblog]

Can I resurrect my first digital multimeter? A Soar ME-533

[R.J.]

Hi Dave,
LCD displays are sensitive to moisture and are hygroscopic.
Moisture will eventually destroy them.
I too have a multimeter from my early days.... My first DMM has the same problem.
I bought this multimeter in August 1980. The display needs to be replaced to ensure future use.
I too am left wondering if I can find another such display.

Greetings from Holland. Holland in Europe. (Not Holland in the USA)

[dieciduej]

I don't have it handy but my first DMM was a Fluke 8050A from I think 1982 or 83.  The LCD started going dark about the early 90s, so I got a good 10 years of heavy usage out of it.  In 95 the company decided to purge the old meters, so I grabbed it and a couple of others still with fading LCDs.  Loved the my bench meter so I plunked down the money and got a replacement LCD for it and it is still in tip top shape and the replacement LCD is still good some 29 years later.

[Rdx]

It seems to be similar to the Akigawa AD-901.
There is also this thread here: https://www.eevblog.com/forum/testgear/akigawa-ad-901-digital-multimeter/

[R.J.]

It's seems to be a SOAR DMM from Japan Model ME-501.
 
https://www.radiomuseum.org/r/soar_digital_multimeter_me_501.html

[EEVblog]

It seems to be similar to the Akigawa AD-901.
There is also this thread here: https://www.eevblog.com/forum/testgear/akigawa-ad-901-digital-multimeter/

Oh wow, I have torn it down before, and you can see how the LCD was 11 years ago:

[Doogs]

I found a couple of meters on ebay canada one being similar to yours. https://www.ebay.ca/sch/i.html?_from=R40&_trksid=p2332490.m570.l1313&_nkw=soar+multimeter&_sacat=0

[R.J.]

Since my digital multimeter (DMM) has a standard display and has no special indications like mV, kOhm or other parameters, I could look for a replacement.
It's a SOAR Corporation DMM...
 

This I have now found from a supplier with the item number Product#: LCD 3.5-13 LOBAT.
For a few euros, I could now replace it.
Also my extra addition for indicating too low battery voltage of the multimeter, works properly.
The separate small PCB that measures the Ref. voltage.
A special segment of the display lights up at a reference voltage lower than 7.8Volt. (So I thought)
That is a sign that the battery voltage is too low.
As a result of a too low Ref. voltage, the multimeter no longer indicates the correct measured values. The display then shows ‘Lo Bat’.
With the old display, only an arrow was indicated.