Elo 1529l

[Iceman_GER]

Hi,
I have 2 identical screens with the same problem. Both show the picture for a fraction of a second. I already ordered and changed the inverters.
(Sampo YPWBGL550IDG)
Friday I got me some caps and replaced all on 1 of the monitors.
I still have the same problem. I suspect the 120uf 400V I did not change.
I have read somewhere that they rarely go but maybe I'm the lucky one.

any help or pointers are appreciated

[stj]

Re: Elo 1529l

are these touchscreen monitors for industrial or arcade use?

[Iceman_GER]

Re: Elo 1529l

they are used in Restaurants, POS systems (point of sales)

[stj]

Re: Elo 1529l

reason i asked is because i was wondering how many hours a day they are on.
they are almost 20years old from the data on the psu.

i would automatically suspect the cfl tubes on something running for so long.
infact i'd be surprised if they hadnt been replaced a couple of times already.

[selldoor]

Re: Elo 1529l

^^^^^^ id go with bulbs/wiring - anything on the screen after the backlight goes off - try with flashlight on the screen at an angle.
Can you post pictures of the other board/boards and a pic showing what goes where

[Iceman_GER]

Re: Elo 1529l

here is a picture of the other screen. I think all redish caps have been replaced at some point.

[stj]

Re: Elo 1529l

https://www.badcaps.net/forum/showth...er+testing+cfl

[selldoor]

Re: Elo 1529l

Hi - On the socket that goes to the inverterboard I see a pin marked on/off.

While the set it being powered up can you monitor the voltage on that pin
Meter on vDC20 -you can just use a ground pin on the same socket for the black probe.

Also many sets wont stay on without a source signal so it may need to be connected to a working pc via the vga socket.

[stj]

Re: Elo 1529l

that's not true, you can press the menu button to get an image up.

[Iceman_GER]

Re: Elo 1529l

Finally had some time to test. sorry for the delay.

i used an old 13" screen to test the inverter. works like a charm, see picture.

[selldoor]

Re: Elo 1529l

Ok - that is great - so can you do a test using one bulb lead from the original and one from the 13"test?

[stj]

Re: Elo 1529l

is that driving 2 tubes at the same time using both invertor outputs?

[Iceman_GER]

Re: Elo 1529l

i really don't think it has anything to do with the bulbs. both monitors have the same problem. they come on for a fraction of a second and go black. i think it's more the power supply

[Iceman_GER]

Re: Elo 1529l

is that driving 2 tubes at the same time using both invertor outputs?

no, used one

[stj]

Re: Elo 1529l

that's not a proper test.
you powered one tube with a circuit designed to power two.
obviously it will be able to overdrive the tube.

i think it's tubes.
both monitors are the same age, and get a hell of a lot of use.

if you research the chip used on the invertors, you can bypass the protection circuits and run the tubes till they burn the wiring or break at one end if that's really what you want to do.

why dont people understand that cfl's are no different to the lamps they light rooms in the house with,
they dont last, they fail after 30-50,000 hours of use. (HP's numbers, not mine)

[budm]

Re: Elo 1529l

Finally had some time to test. sorry for the delay.

i used an old 13" screen to test the inverter. works like a charm, see picture.

since you can use the other lamps of another panel to test your inverter board and the lamps stay on, so that means you have the lamp problem.

http://s807.photobucket.com/user/bud...?sort=3&page=1