Hanns-G HG281D, LCD Monitor no power

[tito_hydra]

Re: Hanns-G HG281D, LCD Monitor no power

There websites might have something for you:

badcaps.net store
https://www.badcaps.net/index.php?pageid=master_list
(international shipping is stated as $9.50

RS components:
http://it.rs-online.com/web/

Farnell/element14
http://www.farnell.com/

or you can also contact member behemot on this forum (he's based in CZ, Europe)

@momaka, I am gonna start the recap of this monitor, i want to change all of the capacitors.
Since i do not have an ESR meter, can you help me to get a full list of the capacitors names? With all the boards on this monitor?
Sorry for bother you, also sorry my bad english.

[SturmGhost]

Re: Hanns-G HG281D, LCD Monitor no power

I think I have an issue with my monitor (HG281D).

Sometimes (happens more often when the monitors runs a longer time) when I scroll down a website some horizontal "artifacts"/distortion appears at 4/5 height of the panel height.
It can't be a computer problem because I build a new one and the problem is still there. A year ago I changed C80 and C83 because of weird on/off behavior of my monitor (it fixed the on/off behavior).

Does anybody have an idea how to fix my monitor?

[budm]

Re: Hanns-G HG281D, LCD Monitor no power

Did you use use good quality caps for the C80, 83?
How about the caps in the power supply board?

[SturmGhost]

Re: Hanns-G HG281D, LCD Monitor no power

Not sure but I think I used:

"RAD FR 100/50 Elko radial, 105°C, low ESR, RM 3,5mm" Brand: Panasonic

Which caps should I replace on the power supply board?

[budm]

Re: Hanns-G HG281D, LCD Monitor no power

OK, you did use PANASONIC FR series.
I would do the recap of the whole power supply board, you may not need to do the main filter cap in the primary side.

[N_R_G]

Re: Hanns-G HG281D, LCD Monitor no power

Which caps should I replace on the power supply board?

Most of times (99%) just replace the three marked in red... Other times It could be necessary replace also the caps marked in blue...

https://www.badcaps.net/forum/attach...8&d=1435812326

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

@momaka, I am gonna start the recap of this monitor, i want to change all of the capacitors.
Since i do not have an ESR meter, can you help me to get a full list of the capacitors names? With all the boards on this monitor?

For the list of capacitors regarding the PSM217-404 power board, see this:
https://www.badcaps.net/forum/attach...2&d=1341463821

Then, use any of the capacitors from the following list:
https://www.badcaps.net/forum/showpo...22&postcount=9

Also get the two capacitors on the LCD logic board, like mentioned here:
https://www.badcaps.net/forum/showpo...&postcount=629

[james2323]

Re: Hanns-G HG281D, LCD Monitor no power

When you hook the power supply to an AC voltage only one output will be 'live' - the 5 volt standby (+5VSB) pin on the 11 pin connector at the end of the supply. If that shows 5 volts, unplug the power cord, hook up the signal card, and check the PSON pin and recheck the +5VSB pin on the same connector. Given the symptoms, I'd expect PSON to be low.

PlainBill

Through reading this very through and informative thread, i have replaced many of the Caps on my HG281D Power supply board (ive replaced about 18 caps on the PS board, the ones most commonly suggested/listed here to be replaced).

When i try to test the +5VSB as described above by PlainBill, (with only the AC main plugged to the power supply board, nothing else) all 11 pins read the same, they all constantly fluctuate between ~ -.13 v dc and ~ +.30v dc (to verify, the way I take this reading: i set my multi-meter to 20v DC and touch the black lead to the ground point coming from the AC IN on the monitor frame (that short green cable that is screwed to the monitor's metal frame) , and this is the reading i get.)

The symptoms that lead me to even open up this monitor (and replace the caps) were that it would flash / power itself off after about 1-60 seconds (i could press the power button several times, sometimes, and get it to repeat the 1-60s) - After i replaced the caps and put the monitor back together, it wont even power on (nor illuminate the blue/orange light)

Anyone have any info as to where i should look for what ive done wrong when i replaced the caps to get this strange DCv fluctuation on the 11 pins (where i was hoping to see the 5vDC so i could the move on to taking readings on the Signal board).

thanks

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

Since your symptoms are worse, and it won't even power on at all now; we could conclude it has something to do with your cap replacement repair.

(1) Make sure the caps were put in the right way according to their polarity.

(2) Look for lifted pads on the solder joints. With that board I remember the manufacturer bent the legs all the way over onto the pads. Unless all the solder is removed, and the legs bent up; it's very easy with that board to pull a pad. I've repaired a few of those AFTER somebody attempted a repair, and every time it was a lifted pad that later caused the problem. When that happens you need to bend the leg of the cap, and connect it to where the the thin copper trace connected to from the cap leg's lifted pad.

Hope that helps.

[morozm]

Re: Hanns-G HG281D, LCD Monitor no power

Dear Forum participants! Need power supply circuit monitor Hanns g 281d.
I will be grateful.

[demoncamber]

Re: Hanns-G HG281D, LCD Monitor no power

I made my own thread

[poltrob]

Re: Hanns-G HG281D, LCD Monitor no power

Hi Everybody,

I am a long time owner of the Hanns G and have experienced problems for years, usually the monitors takes 5/10 minutes after I've turned it on to show picture, after which it's stable.
This week I tried to turn it on but didn't get anything at all from the power led.
I started looking for ways to fix it and happened upon this great Thread !
I have now taken the screen appart and had a look. I'd like to change the capacitors as It's been advised in this thread, but also noticed an issue on the back of the power board, on Capacitor C404 which appears to be burned.

I've searched this thread but it doesn't look like this has been mentionned before so I'd like to ask you what kind of capactior I'd need here (is it a Capacitor ?) as this looks really tiny. Or will it work even without this maybe?

Thanks a lot for your help,

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

I'd like to change the capacitors as It's been advised in this thread, but also noticed an issue on the back of the power board, on Capacitor C404 which appears to be burned.

I've searched this thread but it doesn't look like this has been mentionned before so I'd like to ask you what kind of capactior I'd need here (is it a Capacitor ?) as this looks really tiny.

Could you post some pictures of that? I don't remember off the top of my head what kind of capacitor C404 is. If it's a small tan square/rectangle one, then that will certainly need replacing as it may be shorted. But again, I think it's better we see some pictures first of your board before jumping to conclusions.

[nolse]

Re: Hanns-G HG281D, LCD Monitor no power

Hello
I have a screen hg281d down.
At the start, it cycle on red blue green.
I replace c80 & C83.
I do not have 1.8V to regulator vs18.
The output is short-circuited with ground.
The regulator is ok, the capacitor is ok.
I do not have the schema to find or is short circuit.
If anyone had the schema.

thank you

[budm]

Re: Hanns-G HG281D, LCD Monitor no power

So how many Ohms is at the output pin? <10 Ohms?

[nolse]

Re: Hanns-G HG281D, LCD Monitor no power

regulator vs18 : 1 ohm between output and groud
and regulator not on pcb 700 ohm

[budm]

Re: Hanns-G HG281D, LCD Monitor no power

There should be SMD MLCC (Multi Layer Ceramic Cap) about 0.1 uF connected in parallel with the electrolytic cap that is connected to the output pin of that regulator also, did you remove that MLCC to see if the low resistance will go away?

[nolse]

Re: Hanns-G HG281D, LCD Monitor no power

This is c82 was hs.
thanks.
now the screen turns on but there are red dots everywhere.
The tensions are good.
An idea?

[e76nystrom]

Re: Hanns-G HG281D, LCD Monitor no power

I am trying to repair an HF-289H monitor with a Phihong PSM 217-404-H-R power supply like the one pictured in this link: https://www.badcaps.net/forum/attach...8&d=1435812326

I have done some trouble shooting on the monitor. I have 5v on the 5vsb line with the control board unplugged. When a supply power to the control board the 5vsb line falls to around 2.5v.

I have decided to replace the capacitors and have found all the capacitors 22uf and above from DigiKey, but am having trouble finding the following:

c114 2.2uf 50v
c406 and c108 10uf 50v
c606 1 uf 100v

I can find capacitors with the right capacitance and voltage rating, but none in the series that recommended and none with a specification for ESR.

Are there any recommendations for these?

On the control board there are 23 100uf 16v capacitors. I have also been unable to find a good replacement for these. Are these likely to have failed?

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

I have decided to replace the capacitors and have found all the capacitors 22uf and above from DigiKey, but am having trouble finding the following:

c114 2.2uf 50v
c406 and c108 10uf 50v
c606 1 uf 100v

I can find capacitors with the right capacitance and voltage rating, but none in the series that recommended and none with a specification for ESR.

Hi e76nystrom, welcome to the forums!

Here is a more comprehensive list of capacitors suitable for PSU use:
https://www.badcaps.net/forum/showpo...22&postcount=9

With that said, the following caps should be okay:

for 2.2uf 50v:
493-1887-ND
https://www.digikey.com/product-deta...1887-ND/589628

for 10uf 50v:
493-11421-3-ND
https://www.digikey.com/product-deta...1-1-ND/4319977

for 1uf 100v:
493-1962-ND
https://www.digikey.com/product-deta...1962-ND/589703

On the control board there are 23 100uf 16v capacitors. I have also been unable to find a good replacement for these. Are these likely to have failed?

If they are near "hot spots" such as heatsinks and linear regulators (i.e. 1117 or similar), then they might have dried up.

Again, Nichicon PW, Panasonic FC, and Chemicon KY should be okay to replace those. If you need links, let me know. Otherwise, I will let you search for them as an exercise/homework.