Replacing OLED screen on an Agilent U1253A Multimeter

[alexwhittemore]

Minor update:
The displays finally arrived and they do have the SSD1303 controller. Unfortunately I didn't get anything on the display when I turned everything on. I suspect my soldering is the issue as I've reused the same breakout board and I didn't have any solder wick to make everything nice and level so it was quite difficult to solder on.

I have two so I will try again with the other one on a new breakout board on the weekend...

Well that's exciting 

[eddiea6987]

Well it done!

The tricky part was desoldering the new screen from its pcb because that ribbon is fragile!! And i was not aware of how those things are actually shaped with a gap in the middle.
Good thing I went to desolder the old screen first and messed it up bad. So i was extremely careful with the new one..

I have a picture here simulating, with the hacked up ribbon, how i desoldered the new screens ribbon.
I just heated up a section and gently pulled it off with a blade.

[eddiea6987]

sorry for the lack of details but i typed up that last post so many times and kept getting errors about my pictures being too big.
So ill split it up here are pics of the new screen and the company i got it from.

[eddiea6987]

On a side note, my meter stops charging before its fully charged and I have read on the agilent site that there is a firmware update to fix that but I do not have the
USB adapter for the back of the meter if anyone wants to let me use it, I would pay shipping both ways. Im in florida.

[alexwhittemore]

Well it done!

The tricky part was desoldering the new screen from its pcb because that ribbon is fragile!! And i was not aware of how those things are actually shaped with a gap in the middle.
Good thing I went to desolder the old screen first and messed it up bad. So i was extremely careful with the new one..

I have a picture here simulating, with the hacked up ribbon, how i desoldered the new screens ribbon.
I just heated up a section and gently pulled it off with a blade.

Hey, great news! Now... how do I go about getting one of those displays shipped to California?

Happy to loan you my USB cable - feel free to DM me. But 1) I have the older version that Prolific deliberately kneecapped in Win 10, which requires some trickery to deal with. And the new (orange) version seems to be $33 from Agilent, which isn't wildly worse than the $15 round trip shipping it'll cost to send to you (https://www.keysight.com/en/pd-2314431-pn-U1173B/handheld-digital-multimeter-pc-connectivity-cable?cc=US&lc=eng). Of course, if you'll never use it again...

[eddiea6987]

oh I had no idea it was that cheap, then in that case I might as well get it from keysight, I looked on ebay and saw some well over 100 bucks.
I emailed the LCDStore website someone linked above, they eventually replied and agreed to send me a unit. They asked for money to
be transferred to their bank account, after which I told them I prefered paypal for my own security since they are easier to deal with when getting scammed
they accepted and gave me their paypal

"a payment through paypal is possible to paypal@LC-Design.de
1 piece BL12864G   31,00 USD
Shipment via registered letter   9,00 USD
Payment through PayPal   3,00 USD
SUM  43,00 USD"

their email is  order@lc-design.de

[boborich]

I think I have some good news for you, well, maybe it is too late. Never mind, here you go: https://item.taobao.com/item.htm?spm=a230r.1.14.18.4707da385slyfU&id=556241996733&ns=1&abbucket=19#detail

The OLED module is manufactured by a TW company and someone in CHINA is selling it on Taobao. It cost around 100RMB(including shipping within CHINA), which is about $16 USD.

This will save a lot of 1273 and 125x.

[alexwhittemore]

I think I have some good news for you, well, maybe it is too late. Never mind, here you go: https://item.taobao.com/item.htm?spm=a230r.1.14.18.4707da385slyfU&id=556241996733&ns=1&abbucket=19#detail

The OLED module is manufactured by a TW company and someone in CHINA is selling it on Taobao. It cost around 100RMB(including shipping within CHINA), which is about $16 USD.

This will save a lot of 1273 and 125x.

I've been having some bad luck getting any of these from taobao. They show piles and piles of stock, but then when you actually order, it gets cancelled because they can't fulfill it.

[boborich]

Understand that, just providing info there just in case someone needed that.

[alexwhittemore]

I got the LCD from germany this morning and just finished installing it. Thanks for finding (tooki)/testing eddiea6987!

[tooki]

In all fairness, ultrasmurf found it, and I just used my German to find the vendor.

[alexwhittemore]

In all fairness, ultrasmurf found it, and I just used my German to find the vendor.

Ahh I missed that part! In any event, thank you all! Cant wait to see if any of the (way cheaper) taobao parts actually work.

[Assafl]

It worked for me. Thank you!

Got my display from SOS electronic (same module).

Very hard to desolder the ribbon. It is basically the copper without the underlying PCB substrate. Ended up piling a blob of solder, gently routing it over the top of the ribbon while a stainless spudger lifted the heated section off the PCB. Lost 1 ribbon to it - but there was enough left to solder it in place.

Anyway, Agilent is like new.

Anyone know why these go bad (used or unused?) - is it humidity? Can we seal them?

[nanofrog]

The organic material used to manufacture OLEDs decays. And unfortunately, this can't be helped.

[scopeman]

I have one of the Agilent 34460A 6 1/2 digit bench DMM's that is probably 4 years old and has been powered on 24 hours a day since we go it.

So far no issues but after reading this thread it certainly makes me wonder how long the display will last. I don't think my next DMM will be OLED.

Sam
W3OHM

[tooki]

Isn’t that an LCD in the 34460A?? Should last nearly forever.

[texaspyro]

Isn’t that an LCD in the 34460A?? Should last nearly forever.

Displays in test equipment are my pet peeve...  there is a lot of very nice older test equipment out there that is unusable because of display failures.  OLED displays are at the top of my peeve list.  Life wise they are still not ready for prime time.

LCDs do fail.  Newer models are quite a better than earlier ones that had problems with defective seals, spacers, and polarizers.   As an example older Fluke DMMs are notorious for bad displays.

VFDs are well known to wear out due to cathode and phosphor aging.  They are almost always custom models that are rather impossible to source if you need a replacement.  Gas discharge displays (like Burroughs Panaplex displays are similarly affected.

If you want a long lived or serviceable display in your test equipment look for displays that used standard 7-segment LEDs... followed by monochrome LCDs (but check the interwebz to make sure the model does not have some well known LCD problems).  Oddly, nixie tube displays seem to hold up quite well and replacement tubes can still be found.

CRT based displays can often times be retro-fitted with LCD video displays.  You will probably need to do some mechanical work and tweak the display and sync signals.

[Assafl]

7 segment LEDs are indeed the longest lived of the bunch. Mechanical indicators are also long lived. A never-before-dropped high quality d'Arsonval movement may indeed last nearly forever....

The OLED in the Agilent died although it was used rather rarely. I am beginning to suspect that the Solomon Systech OLEDs have a problem with humidity. I wonder if putting a satchet of silica gel would help extend its life. Or dunking it (at least the seams) in Varnish.

[nanofrog]

Isn’t that an LCD in the 34460A?? Should last nearly forever.

The 34440A's I'm familiar with all have VFD's, not OLED's. 

[tooki]

Isn’t that an LCD in the 34460A?? Should last nearly forever.

The 34440A's I'm familiar with all have VFD's, not OLED's. 

There is no 34440A. Are you thinking the 34410A? Either way, that’s not the same as the 34460A.

I checked, the 34460A (still part of Keysight’s latest crop) is an LCD, as I thought: https://literature.cdn.keysight.com/litweb/pdf/5991-1983EN.pdf?id=2318052

(It says it’s a 4.3” TFT with LED backlight.)

Isn’t that an LCD in the 34460A?? Should last nearly forever.

[...]
LCDs do fail.  Newer models are quite a better than earlier ones that had problems with defective seals, spacers, and polarizers.   As an example older Fluke DMMs are notorious for bad displays.
[...]
If you want a long lived or serviceable display in your test equipment look for displays that used standard 7-segment LEDs... followed by monochrome LCDs (but check the interwebz to make sure the model does not have some well known LCD problems).  Oddly, nixie tube displays seem to hold up quite well and replacement tubes can still be found.
[...]

But standard LCD modules like 1602’s and most color TFTs are so standardized that replacements should be available for decades to come.

And while early LCDs did have troubles like you mention, I don’t think those have ever been common in TFTs, since by the time those came along, LCDs were already mature technology. Look at early 1990s laptops: their displays still work just fine.


The person I was replying to (while on the go, hence not doing extensive googling) seemed to be worried about the LCD in the 34460A. I think there’s absolutely nothing to worry about. I don’t think it’s likely to fail, and even if it did, I suspect it’s fairly easy to find a replacement that will work.

[nanofrog]

Isn’t that an LCD in the 34460A?? Should last nearly forever.

The 34440A's I'm familiar with all have VFD's, not OLED's. 

There is no 34440A. Are you thinking the 34410A? Either way, that’s not the same as the 34460A.

I checked, the 34460A (still part of Keysight’s latest crop) is an LCD, as I thought: https://literature.cdn.keysight.com/litweb/pdf/5991-1983EN.pdf?id=2318052

(It says it’s a 4.3” TFT with LED backlight.)

You're right; I was looking at a 34410A.   

Seem's only the older models came with a VFD (example), whilst the current production is LCD. FWIW, I'm a huge fan of decent used gear, so it's not a big stretch for me to not have recognized there was a change in displays. 

My deepest apologies. 

[tooki]

I mean, as much as the color TFT enables things like graphing, there's just something special about a really nice VFD.

(For a lab power supply mod I'm working on, I've been thinking of using 1.9mm pitch LED matrix displays to achieve a kind of similar effect.)

[Assafl]

I am still trying to figure out why the OLEDs die so quickly (whether the DMM is powered or not). So I tried measuring the voltage on the connector to the OLED daughterboard (the black silkscreened board) when powered down (off/charging position) and it seems like the connector sends power to the card even when powered down (about 1.5V worth of voltage).

I failed at tracing where it goes on the daughterboard - I may try this again at some time - the black silkscreen makes it difficult to figure out the traces.

Could the DMM cause the burnout of the screen because it biases it even when off?

[nanofrog]

I mean, as much as the color TFT enables things like graphing, there's just something special about a really nice VFD.

(For a lab power supply mod I'm working on, I've been thinking of using 1.9mm pitch LED matrix displays to achieve a kind of similar effect.)

Although I can't say precisely why, I'm absolutely 100% fond of VFD displays over OLED, TFT, and othewise.

I guess I'm an old git these days (just shy of 47  ).   

[tooki]

I mean, as much as the color TFT enables things like graphing, there's just something special about a really nice VFD.

(For a lab power supply mod I'm working on, I've been thinking of using 1.9mm pitch LED matrix displays to achieve a kind of similar effect.)

Although I can't say precisely why, I'm absolutely 100% fond of VFD displays over OLED, TFT, and othewise.

I guess I'm an old git these days (just shy of 47  ).   

I’m on my last month of being 37 and I agree!