Replacement display for an Elka MK76

[The Elf]

The backlit LCD of my MK76 has died.

Can anyone tell me, in terms an electronics novice can utilise(!), what I need to order, and maybe from where, to replace it? Hopefully I can do the job myself.

The schematic mentions 'LC DISPLAY L M 016L'.

This? https://www.ebay.co.uk/itm/143055616621?epid=1165670176&hash=item214ec77a6d:g:sWQAAOSwvERcF~ZD

If so, can I be sure it will fit as is?

[Hugh Robjohns]

Just to be clear, is it the actual LCD (or its driver) that's dead, or the (back) light?

[The Elf]

Just to be clear, is it the actual LCD (or its driver) that's dead, or the (back) light?

It's just the backlight - the torch says!

[Hugh Robjohns]

Try shining a light in from above -- a pencil torch or the light from your smartphone (you may need to experiment with the angle) -- and see if the display is still showing the correct information or if it is blank.

[The Elf]

Try shining a light in from above -- a pencil torch or the light from your smartphone (you may need to experiment with the angle) -- and see if the display is still showing the correct information or if it is blank.

Sorry - my edit crossed your response. Yes, a torch says the display is there - it's the backlight that's gone.

[fatbenelton]

https://instrumentalparts.com/mk-76-mk- ... backlight/

[The Elf]

https://instrumentalparts.com/mk-76-mk- ... backlight/

Thanks. It looks cheaper to buy the whole display from those on eBay.

And easier to install - as long as it will fit?

[Guest]

The schematic mentions 'LC DISPLAY L M 016L'.

Do you have a link to the schematic?

[The Elf]

https://www.dropbox.com/s/glbtu267pexx5fu/mk76schem.pdf?dl=0

[The Elf]

I decided to spring for one of those eBay offerings. It's only a tenner, including postage, so worth a try.

[Guest]

The 16 pins sort of match up (table 2) : https://embeddedcenter.wordpress.com/ec ... x2-lm016l/

I'm a bit confused that is says that of the extra two connections (15/16) one isn't connected to anything but both are on the schematic so the numbering may be even more wonky, especially as one looks like it would be the contrast adjustment which should be pin 12!

I bet if you plug it in it will work though.

[The Elf]

Well...

First came the nightmare of trying to figure out how to open the case - half an hour of utter frustration and bafflement followed by one moment of disbelieving realisation. Little did I know...

The true horror of the situation soon began to unfold. The existing display was soldered in - wire by wire. Only two colours were used for the wiring, rather than the friendly rainbow of delight adorning the replacement. No one-for-one wiring match-up then. The replacement display seemed to be giving me a 'knowing' grin.

After a bit of indecision and head-scratching I decided it would be better to simply swap over the backlight. It should be easy enough - remove the tin display cover, unsolder two connectors, pull out the fluorescent strip and replace with the new one.

I removed the display cover and saw the light strip underneath. The display portion itself fell away from the circuit board, leaving no trace, or clue, as to how it been attached. I could see no connections for it - it simply sat on two 'silicon'(?) strips. How the heck does *that* work? No metal connections; no pins, no obvious point of attachment?! Moving the panel and its 'silicon' mounting strips around over the circuit board produced a few lines on the LCD - but no clue as to where was the right position. Heck, I didn't even know if I'd got the strips in the right place, let alone the panel. OK, I'd figure that out later...

I removed the cover of the replacement display (which also fell apart)... to find it had no backlight strip. If my car wasn't parked under the window there would be a dent in the driveway tarmac right now.

Life is too short. Another piece of landfill, a few day's of regret and it will all be over. At least I now have a space to fill with a new toy - pity it won't have poly aftertouch though - and certainly not 76 keys of poly aftertouch, even if it did.

Elf's Elka MK76 - RIP 2021. I'm going to miss you, girl...

[Hugh Robjohns]

FFS.... tame experienced tech, proper parts. Job done. Please don't skip a perfectly serviceable and mendable bit of kit.

[The Elf]

Well it's more than my time is worth. If anyone wants it let me know. Everything I removed is inside the case.

[Tomás Mulcahy]

But it's a Poly AT board! If I was on the same island I would drive to you to collect it. I'm sure someone will.

Pity you didn't wait a little bit longer, posted pics of the innards etc. we could've helped I've done a few displays so I could help. My Akai MX-1000 has an iPhone 6+ backlight in it (common thing people are doing with Akais of that era) the Casio FZ-1 has something similar, and I'm just doing a Quadraverb now.

Replicating the wiring is easy- use a smartphone and make a video as you remove it. Displays with backlights come in two kinds- displays where the backlight is glued/ manufactured in (so it breaks as you discovered) and displays where they are not

[The Elf]

I'm still licking my wounds right now. In a few days I may bring myself to take it to the local repair shop, but at the moment I'm utterly p£$%ed off with it.

It was only 80 quid, so no complaints in that respect. It's done me fine for a while, but to throw any more time and money at it? Hmmm... Not convinced.

[Tomás Mulcahy]

I know the feeling!! I had a few issues with the MX-1000, it was sitting on my bench for 6 months. But it was more annoying not having a decent weighted keyboard so I got there in the end. It's a beautiful bit of design, sleek curved aluminium case. And it's a rather neat MIDI controller. The 4 sliders work great for the 4 macros in Arturia.

This should be straightforward for any tech who works on hifis or phones or computers.

On a related note, I was not a fan of poly AT when I tried it on a GEM Equinoxe. But I am really starting to love the ROLI Seaboard Rise 49. Obviously this board is worth it to you, as a Poly AT controller. Put it away for a while

[The Elf]

On a related note, I was not a fan of poly AT when I tried it on a GEM Equinoxe. But I am really starting to love the ROLI Seaboard Rise 49. Obviously this board is worth it to you, as a AT controller. Put it away for a while

Poly aftertouch is addictive - once you 'get' it, you don't want to be without it. In my case I have the Hydrasynth - easily the best feeling aftertouch in my studio - and a Roli Seaboard 25.

I'd love a Roli Seaboard 49. I've had two, both of which arrived faulty from new. If I could find a fully functional secondhand one I'd leap on it!

[fatbenelton]

Shame, but put it to one side rather than skip it. Prob a easy fix for somebody with more experience!

Incidentally, you may remember my issue with Poly AT on my MK88. Well, as it’s working fine other than that I just left it but decided to open it up and have a look a few weeks back as I’m convinced it’s just a loose wire.....Anyway, couldn’t figure out how to open it up so gave up!
How did you do it?

[The Elf]

I'm glad it's not just me!

Look on the outside ends of the case - three screws on one side, two on the other. Then there's one more middle back. Remove these, then ease up the main panel.

I was scratching my head for a long time on that one!

[fatbenelton]

Great - thanks! If it’s visible I’ll take a pic of how the display should look!

[Folderol]

It's quite common for this type of display for the connections to be made to the actually screen itself via conductive rubber (the current is microamps, it's the voltage that twists the pixels). Unfortunately the positioning has to be absolutely perfect

On a number of occasions I've found the best way to get a 'replacement' backlight, is to find a transparent edge, and line up a strip of LEDs to it.

[James Perrett]

On a number of occasions I've found the best way to get a 'replacement' backlight, is to find a transparent edge, and line up a strip of LEDs to it.

I think that's how the modern LED backlights work anyway - whereas the old ones had a fluorescent layer. There's a Facebook group dedicated to replacing displays on music gear - reading all the posts it seems that most of the time a standard display drops almost straight in.

However, I have a piano module that I've been trying to fix for someone for a while that needs a very narrow 2 line display and I've not found anything that will physically fit.

[The Elf]

It's quite common for this type of display for the connections to be made to the actually screen itself via conductive rubber (the current is microamps, it's the voltage that twists the pixels). Unfortunately the positioning has to be absolutely perfect

Yep, that's my guess. I think even if I could get a replacement light strip I'm dead in the water.