September 21, 2019, 09:47:04 pm

MegaPixel LCD

Started by barcher174, December 27, 2014, 01:45:47 am

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barcher174

Hi All,

I did a little arts and crafts today and integrated a soundboard directly inside an LCD. Power now comes directly from the next and uses the original 19pin cable. I needed to step down 12V --> 5V for the internal monitor logic board. The soundboard easily fit in the space left over from removing the original power supply.

Everything fits and mostly functions. I'm still trying to track down an issue where there is a slight "wave" in the picture which I'm thinking is a problem with wire length for vsync and hsync.

For now it functions well enough. I had the spare monitor and sound board so this was mostly just to see if I could.

Gallery here:

https://www.dropbox.com/sc/ncz2b7bzm24on7y/AABCogevJe2HowZlFLkNa7g_a

I'll do a write up after I get the remaining issues sorted out, but wanted to put this idea out there for those considering doing a bare board conversion and have no case.

--
Brian

pentium

WOW! It's so clean too. Just put a lablled bezel over the connectors and it would be amazing.

Write that up and submit it to Hackaday because that there is a winner of a project. Also, try looping the sync and video wires in a ferrite bead. You could be picking up interference from the backlight inverter.

-NeXT 68040 Cube with NS 3.3 and 64Mb ram

barcher174

Thanks Pentium. The rolling turned out to be a ground issue. I grounded the Dsub shell to the chassis and that seems to have solved it. I didn't really take a lot of time on making the ports look pretty because it's not visible when upright.


barcher174

Well looks like you were right. It made hackaday. :)

--
Brian

pentium

Fuelled your success I'm about to undertake the same mod and see what I can get out of the NEC Multisync LCD 1545V. According to the internet it can't handle a NeXT resolution but it seems to do 1280x1024 so it should be able to scale down a little. I got nothing to loase as the LCD was free.
It has a nice and deep back which you can fit the digital board inside the monitor with and it seems the main LCD controller can be flipped over and just barely fits out of the way. The only downside is it's a 5V monitor, so a regulator is needed to step the 12v from the NeXT machine down to a voltage the inverter and digital board is happy with. Again though, lots of space in here. I'll try and get pics tomorrow after I finish mounting the boards.

-NeXT 68040 Cube with NS 3.3 and 64Mb ram

barcher174

Awesome. Excited to see it.

pentium

As promised.





I discovered that the Panasonic 16v 1500uf capacitor had begun to leak when I removed it. You have to reposition it on its side or the board will not fit in the monitor.

I also realized I forgot to buy the regulator I need to power everything.

-NeXT 68040 Cube with NS 3.3 and 64Mb ram

barcher174

Looks super clean. Awesome!

pentium

Something isn't perfect yet. While the panel worked flawlessly in testing (no point modding a defective panel) now that we have most of it assembled if I power it with 5v off the bench while the LCD runs fine the backlight immediately kicks out. Either it doesn't like the extra long ribbon cable that links the LCD's digital board (there's two wires that presumably control the backlight) and the inverter, or I missed something when analyzing the old power supply and the inverter wants something other than 5v.

If all else fails though this makes the panel an excellent candidate for a full conversion from CFL backlighting to LED.

Also, if anyone is curious I am using NEC's LCD1545V 15" display. It's available in both black or white trim and while supposedly its resolution is 1024x768 I saw it running at 1280x1024 so hopefully it will be happy with the oddball resolution NeXT used that's somewhere in between.

-NeXT 68040 Cube with NS 3.3 and 64Mb ram

barcher174


Rob Blessin Black Hole

Rob Blessin President computerpowwow ebay  sales@blackholeinc.com http://www.blackholeinc.com
303-741-9998 Serving the NeXT Community  since 2/9/93

pentium

Quote from: "barcher174"The backlight runs on 12V. Full service manual here: http://www.manualslib.com/download/871055/Nec-Multisync-Lcd1525v.html
That is the 1525. Even in the photos the backlight inverter is of a different design.

Say Rob. Would you have any small NeXT logos? I could slap on this once I've gotten the unnecessary NEC silkscreening off.

-NeXT 68040 Cube with NS 3.3 and 64Mb ram

Rob Blessin Black Hole

Hello Pentium: Yes, I have a small logo how about $5 and I can probably drop it in an envelope to Canada for $3  Best Regards Rob you can just paypal me and I'll send an invoice just need your paypal address . Send it to sales@blackholeinc.com
Rob Blessin President computerpowwow ebay  sales@blackholeinc.com http://www.blackholeinc.com
303-741-9998 Serving the NeXT Community  since 2/9/93

pentium

I will keep tabs on that once this is finished.

-NeXT 68040 Cube with NS 3.3 and 64Mb ram