Blew out some pixels in LCD (static)

[dgriff]

So I got back to my office after lunch and must have charged myself up with static - went to adjust the selector knob on the LCD panel as the unit was printing from SD card and saw a small spark jump from my fingers to the metal frame surrounding the LCD panel (which immediately went blank, then came back with a few lines of scrambled characters). Crap...

After turning it off and on again (standard troubleshooting technique), everything is back to normal - with the exception of the bottom 20 or so pixels in the first column on the left. (don't mind the nozzle temp reading, it was just fluctutating a bit as I took the photo). Note that the first line for the "Speed" and "Killed" is now missing.

[img]http://i.imgur.com/xp6F4MZl.jpg[/img]

Anyone have any ideas for a fix that doesn't involve replacing the entire panel? It's not earthshattering (and only around $50 for a replacement), but is a bit annoying.

In the meantime, I might suggest rigging up a grounding strap from the metal frame around the LCD directly to the power supply housing to prevent future issues.

Dave

[geneb]

Jameco sells the LCD display itself.

g.

[dgriff]

Jameco sells the LCD display itself.

g.

Hi Gene,

Thanks for the heads-up, looks like this is the part here:

[edit: ya, this was the wrong part - it's a character display, not a bitmap display]

I can see the issue from the reverse view of the circuit board - there are a number of bendable metal tabs used to keep the aluminum front faceplate on, and some of those bent tabs are extremely close to the traces on the board - The static spark must have jumped from the tab to the trace and caused my issue.

Luckily it should be extremely easy to add a grounding strap to a tab and run a line back to the casing of the PS.

[Eaglezsoar]

Jameco sells the LCD display itself.

g.

Hi Gene,

Thanks for the heads-up, looks like this is the part here:

http://www.jameco.com/webapp/wcs/stores ... 2190397_-1

I can see the issue from the reverse view of the circuit board - there are a number of bendable metal tabs used to keep the aluminum front faceplate on, and some of those bent tabs are extremely close to the traces on the board - The static spark must have jumped from the tab to the trace and caused my issue.

Luckily it should be extremely easy to add a grounding strap to a tab and run a line back to the casing of the PS.

At the price Jameco wants for that display you would be better off just buying a new display for an additional $10 or so.

[Eric]

I think you incorrectly eyeballed and linked a graphic display from Jameco, which means the wrong price as well.

It's much more likely to be this character-based display: http://www.jameco.com/webapp/wcs/stores ... 2190362_-1
Or the equivalent from ebay: http://www.ebay.com/itm/New-2004-204-20 ... 0730910251

Living with the one you have doesn't seem so awful either. You probably lost those pixels permanently, but it's still usable.

[geneb]

The Jameco part that Eric found is likely the correct one. It's wiring matches that shown here:
[img]http://reprap.org/wiki/File:SmartAdapter.JPG[/img]

g.

[joecnc2006]

The Jameco part that Eric found is likely the correct one. It's wiring matches that shown here:
[img]http://reprap.org/wiki/File:SmartAdapter.JPG[/img]

g.

image is not attached can not see it.

[geneb]

Stupid forum.

http://reprap.org/wiki/File:SmartAdapter.JPG

g.

[barry99705]

Stupid forum.

http://reprap.org/wiki/File:SmartAdapter.JPG

g.

You know the old saying, "you gotta be smarter than the equipment your operating".

[dgriff]

Well the screen finally decided to get worse, and the bottom two rows of characters completely gave up the ghost.

Ordered the replacement screen that was found on Ebay for $8. Will change it out when it arrives and check back in with a status report (will be either "all good", or "ordering complete new module" )

[dgriff]

Fixed!

After my original screen finally failed completely, I decided to purchase the $8 replacement screen off of Ebay (http://www.ebay.com/itm/New-2004-204-20 ... 0730910251). It worked perfectly (thanks Eric!)

It was a pain in the butt to get the old screen out by unsoldering the long row of connection pins at the top of the display (I didn't have solder wick, and my solder sucker was ineffective - anyone else have a better method?). Fortunately due to the length of the pins and the plastic standoff below, I was able to heat the top and gently pry it off with a screwdriver - piece by piece.

After putting the new screen on (and soldering it in was a breeze, compared to taking the old one off), I needed to make a minor adjustment to the screen contrast pot on the back of the connection module. The pot is very sensitive, just touching it will make the difference between showing clearly and being too bright or not visible.

[img]http://i.imgur.com/f52NDUel.jpg[/img]

Back in business!

I did scrape the paint off the bottom of one of the metal tabs on the back of the display and soldered on a grounding wire that I ran back to the power supply to prevent future static issues from causing more screen issues.

[Eaglezsoar]

Excellent job!

[geneb]

When you're replacing a dead part, it's often easier to gut the pins off the device and then use a solder sucker to remove the remains of the pins & solder from the holes.

I don't know if the pins on the LCD would allow that though.

g.

[dgriff]

I don't know if the pins on the LCD would allow that though.

Ya, that would have probably worked if I cut them in the middle with a dremel cutting wheel and then unsoldered just the pins. Unfortunately I didn't have the 16-pin standoff header available to replace it on both circuit boards, so I needed to find a way to re-use the old one.

Wasn't elegant, but it worked

Dave

[nitewatchman]

At $8.39 I ordered one just to throw in the drawer.

Thanks for the search to find the replacement part.

nitewatchman

[geneb]

I'd love to find one of those with red letters on a solid black background. I saw a yellow/black one on a machine at MRRF and it looked awesome.

g.

[Eric]

I'd love to find one of those with red letters on a solid black background. I saw a yellow/black one on a machine at MRRF and it looked awesome.

g.

This manufactuer lists many color combos, including amber on black: http://www.oppod.com/products/c-32-1.html
They probably have a minimum order, but you can ask.

[Eaglezsoar]

I'd love to find one of those with red letters on a solid black background. I saw a yellow/black one on a machine at MRRF and it looked awesome.

g.

http://www.411techsystems.com/20x4-Blac ... _p_53.html

[geneb]

Eagle, that's actually white on red.

Eric, it doesn't look like they supply an FSTN Negative display with red characters. It's ok.

g.

[Eaglezsoar]

Eagle, that's actually white on red.

Eric, it doesn't look like they supply an FSTN Negative display with red characters. It's ok.

g.

I looked at it again and it says "Red Text on black background" Even the picture shows red text on black background.
Gene, I think you should take a second look.

[geneb]

It's white (or gray) on red.

g.