rtw Porta-Monitor -> new Display

Hello Forum,

a coincidence made me own a rtw Portamonitor 1064-plus. The drawback is that it needs a new TFT-display. Has anyone around here ever touched the insides of that unit? The PCB of the display says it's an NEC "55PW142-B" but I couldn't find anything on this on the whole web. So is there any idea what display fits here without trouble? And maybe where I can get hold of one in Germany or Europe? I cannot afford the "original" replacement-part from rtw, so please don't direct me this way

thanks in advance

Chris

Problem solved! 

The real name of the display was NEC NL3324C35-01.

Two peolpe seemed to have the same problem but couldn't find the right display. I think the problem is I mixed up the model-number: Should be NL3224C35-01 instead of NL3324.

Don't know if this is close but

http://www.ebay.co.uk/itm/NEC-NL3224AC35-06-TFT-Panel-LCD-Display-Screen-/321063939219?pt=UK_Replacement_Parts_Tools&hash=item4ac0e6ec93

..... good seller,  had a couple  items from him, 

BTW thats the cheapest there are more !

s2udio,

I'm not sure if this would do. It's a -06 instead of -01 and also looks a bit different. IIRC the last numbers have something to do with the displays speed. But for a not 100%-sure thing I personally wouldn't pay that much. The -01's show up from time to time and are in about the same price-range. I found one second hand for 20€.

What would be interesting is if people knew about savnat-models or other gear where this panel was used. So one could search for these as organ-donors.

Hey Guys, I have the exact same meter with the exact same issue and am looking for some input.

I bought the RTW Porta-Monitor without the power supply and it has a weird connector so I installed a standard switchcraft power jack and used a 24v 1.5 amp power supply.  When I fired up the meter for the first time the screen blinked once, then went to a semi lit black screen with nothing on it.  A friend of mine told me that usually with these meters it is the LCD that goes bad, but with his it didn't even light up, it was just solid black.  I purchased the proper part number LCD refurbished on ebay from NY for $100 (they are asking $200 but I made a best offer).

If anyone has any other input on the LCD being bad or if it might be something else please let me know.  I'm definitely not an expert on LCD's.  It seems like the backlight is working, but there's no input to the screen which makes me think it's possibly that the screen is not the issue.  I guess I'll find out in a few days when the new LCD gets here.

Didn't you go through the Datasheets? -> RTW_DATASHEET_1063
It clearly says "Binder 710 4-pin", which is not that difficult to get. Binder 710
On some (I think, the not-"X"-Versions) but not all units you can also feed the +24V via the 25-pin D-Sub.

Current-draw shouldn't be the problem with your supply, so most probably the display. Prepare for a bit annoying exchange-procedure... The display is glued in with some white stuff that you have to cut with a sharp knife. As well it is glued to the front of the rtw with tape which you cannot see but you need some soft strength to rip it off the front. No screws though... And the new display needs to be reglued somehow again. But first make sure, it works! Let us know if it works!

Yes I read Binder series 710 connector but that's not common here and since I don't have the original PS it doesn't look like the female end is solderable, so I installed a higher quality switchcraft setup.

Yeah the screen is glued with RTV. A little Xacto action will cut it loose and some firm thumb pressure on the front.  I'll use a little less RTV when I put it back together .

The screen is on order so I will let you know if it works.

Thanks!

I have the data sheet, but does anyone have schematics for this?

I replaced the LCD with a refurbished one I bought on ebay for $100 and it works great.  Just to recap the symptoms, when I would power up the meter the screen would flickr a couple times, then it would go black.  You could tell the LCD was on, but you couldn't really see anything on it.

Yeah, some time has gone. Hope somebody sees this and spreads it.

The RTW Porta Monitor 1062, and similarnumbers, seems to have a common problem: The screen blacks out after a few seconds after powering up. I just had this case and could repair it.

No way to get schematics from RTW, but the screen inside is made by NEC and the specs (datasheet) are to be found as a PDF document in internet, as commented elsewhere in this forum.

Datasheet says: The input supply voltage to the display unit is supposed to be close to 9.5 V, recommended 9-10 V, max 13 V, for unit operation. Absolute max V (destruction point) is 20 V. Checking the actual voltage, in my case it read 15 V (flatcable pins 17, 18, 19 ?? Or was it 18,19,20??). Above operation V, below danger V, that is. So I guess the monitor goes into protection mode of black pixels, and disconnects parts of the circuitry.
Anyway the first power supply IC, the outermost IC on the cooling sheet on the mainboard, is the one responsible for the 9.5 V. IC 2 produces 5 V. Both are switch-mode and have 5 legs. The IC supply input is taken from the 24 V external input, reduced a little bit in the third cooled IC, or really a darlington PNP transistor. The IC output, pin 2 (terribly noisy signal), goes to a series coil and a storage capacitor to remove the noise. This point is the IC supply output DC voltage point = coil/cap point.
I did not try to find out why the IC supply output voltage had risen. Instead, I increased the feedback (to reduce output V) by setting a 18 kOhm resistor between Coil/Cap output point (used to be 15 V DC) and FB (feedback) point, IC  pin 4. This did put the IC supply to 9.4 V, just right. You may have other voltages and must use another R value.
The display stayed on after this; the unit was as new again.

Bumping this old topic , cause i tried the "mod" suggested by kjellelec on a 1063 plus and it worked .
Anybody done this  too and can comment on long term stability ?
Will the Voltage rise again without repairing the initial cause of the problem ?