Help with a DPS12i - display issue

Hi everyone,
Well I've been searching online for the solution to this issue I'm having with a DPS12i I just picked up.
Basically It boots up fine but for some reason the display area doesn't have a light/lights up when on.

I downloaded the manual to the dps and only found the contrast control part where I can adjust it but no information about turning on the light source to the display panel.

I just wanted to know 1st, if the dps12i actually has a light in the display panel ?
(I've seen some pictures online of the device and see a clear white type light in the display area)

2nd, if their is a light source to the lcd display where can I adjust the setting to actually turn it on...

really new to this and I got this device with a ReQuest arq1 add-on that was used with it (something else i'll have to read up on)

So I'm just stuck here at the moment, well thanks for hearing me out

simonbelmont wrote:Basically It boots up fine but for some reason the display area doesn't have a light/lights up when on.

The LCD of the DPS12 has a Cold Cathode (CCFL) backlit display instead of the electro-luminescent (EL) foil found in lots of other old hardware (MPC60, MPC3000, S950, S3000XL etc). When it dies, you still see the text on the LCD, but without any light behind it.


Case removed, LCD at top left.

Close up of LCD.

Front view.

It is essentially an MPC2000 screen, with the ribbon cable inverted, same part number.

The LCD should be lit the same as an MPC2000 screen.

peterpiper wrote:If you need to replace the cold cathode tube be VERY VERY careful cause one false move or deassamble to rough and you can throw the display into the garbage cause you'll get those well known black or blank lines in the display.

Here are some photos I made when I thought about getting a coldcathode in another color. I didn't replaced it tho (back then I didn't know how crazy it is to open the diplay without a reason I had luck. No lines accrue)






see this plastic foil with all the contacts? BE VERY CAREFUL WITH IT. dont touch it or bend it to much, dont heat it up or whatever!






This is the coldcathode tube










peace

MPCHunter wrote:Replacement CCFL tubes are still available to purchase. Something like this should work:

http://www.mouser.com/ProductDetail/JKL ... eVM6oNJUqT

As peterpiper noted above you must be careful that you do not damage the ribbon cable when changing the CCFL tube. Replacing the tube is not necessarily difficult, just time consuming as you have to bend the leads to fit inside the housing and make sure everything fits correctly.

It is possible to repair missing lines on the display if you have the skill set and tools to reflow the fine pitch soldering of the ribbon assembly. When these types of assemblies are manufactured they use a hot bar to bond the flexible ribbon to the LCD. I've used a very fine point soldering tip to reflow a few solder joints, however it can be more trouble to repair than it's worth as you run the risk of causing other issues.

The inexpensive cost of these tubes is why you have not seen a drop-in LED replacement.

So the bottom line is, technically it can be repaired or replaced, but if you intend to do it yourself chances are you'll make things worse, if you're not experienced at such repairs. It appears that you have been sold a LEMON, maybe time to quit while you're ahead...unless you can live without the backlit display.

thanks for the info man
good thing is that i didn't get hosed for a big amount
but me trying to fix it, i don't really see that happening

i could probably deal with it like this but, eh.....

thank you again for the info above^

Working without a backlight is slightly inconvenient, but most of us have done it.