Hanns-G HG281D, LCD Monitor no power

[Severene]

Re: Hanns-G HG281D, LCD Monitor no power

OK found it. Post #727 from Castor8 7th image. Will try to re-post the image here in case anybody needs it.

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

I don't have those values. Sorry. I think if you go through the entire thread you'll find a pic somewhere. Or google images.

I make it a habit of replacing 1 or 2 at a time because I don't want to write it all down. And I can't remember more than 1 or 2 at a time. Works for me.

[Severene]

Re: Hanns-G HG281D, LCD Monitor no power

Do you have a list of those values? Somebody moved all my caps from my work bench... I had them setting in position to where they came out. Should have wrote them down...

Yeah I noticed the leads bent down. Tried pulling them straight with the iron and almost flicked solder in my eye. I know I had some safety glasses around here somewhere...

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

The microfarad value needs to be the same. The voltage can be a little higher. A 100uF 16v cap can be replaced by a 100uF 25v cap. You'll need to replace the 3 I had circled in red for sure. Those 3 always go out. I'd replace all the small ones in the middle of the board just to be safe.

You need to be careful on that board because the manufacturer bent the cap leads all the way over. So when people melt the solder, and pull on the cap, it can take the copper trace, and/or the pad with it. I like to melt the solder and stick a tiny screwdriver in there, and bend the wire lead up a little at first. Then pull it out.

[Severene]

Re: Hanns-G HG281D, LCD Monitor no power

SO, I have the Hanns G power supply thats the easier of the 2 to fix. I ordered a kit prior to understanding that. The kit doesnt have a few of the caps outlined in red for some reason. Ive already taken out C605, C606, C603, C707, and C403. I read on another forum a guy replacing some of the larger caps with different values. Am I suppose to replace these with the same values or are there alternate replacements?

Please advise. Thanks.

[hapollo]

Re: Hanns-G HG281D, LCD Monitor no power

Hi Hapollo. You know, I have never had one of the alternate power boards like you and BtB have to repair. It's always been the one I will attach here. But since your board was manufactured around the same time that many manufacturers were using the inferior caps; there's a good chance you have some bad ones. You could replace them all (If you are fairly skilled and have the time). I have an ESR meter so I can test them. In my experience on the other board, it was the smaller caps that tended to dry up. Especially in the middle. It's really up to you. If I didn't have an ESR meter, I'd start with the smaller caps that aren't bulging. Or just replace them all. Hope that helps.
P.S. I did hear of a guy that fixed your board by replacing some caps. But I don't know which ones he replaced. So there is hope
And you want to replace the 2 caps budm mentions on the logic/main board (photo attached)

Thanks Lumberjack777, I don't have a ESR meter but have replaced many many caps on defective LCD TVs from the 2008 era, mostly Samsungs and typically those have been the larger 1000uf or 2200uf. Rarely have I had to replace anything less than 100uf.

These Hanns seem to be the reverse, mostly small <100uf fail and the larger ones seem ok. Having read your earlier post that it's always the same smaller ones and a waste of time and money to replace the larger ones:

https://www.badcaps.net/forum/showth...451#post504451

As with any small qty cap purchase orders, the shipping is typically greater than the cost of the dozen caps. Guess I will order the whole lot that BtB listed, start with the smaller ones and then progress to the larger ones if after just replacing the smaller ones don't work.

Maybe it's time to invest in an ESR meter

Thanks for the quick reply and HAPPY 4th!

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

Hi Hapollo. You know, I have never had one of the alternate power boards like you and BtB have to repair. It's always been the one I will attach here. But since your board was manufactured around the same time that many manufacturers were using the inferior caps; there's a good chance you have some bad ones. You could replace them all (If you are fairly skilled and have the time). I have an ESR meter so I can test them. In my experience on the other board, it was the smaller caps that tended to dry up. Especially in the middle. It's really up to you. If I didn't have an ESR meter, I'd start with the smaller caps that aren't bulging. Or just replace them all. Hope that helps.
P.S. I did hear of a guy that fixed your board by replacing some caps. But I don't know which ones he replaced. So there is hope
And you want to replace the 2 caps budm mentions on the logic/main board (photo attached)

[hapollo]

Re: Hanns-G HG281D, LCD Monitor no power

hey thanks for the help
the pics posted of the power board are not the same as mine, I managed to snap a few pics but they are not of the best quality. Its the best I could do without buying a camera.

So I will just recap the entire 2 boards and see how that goes. here is the cap list

logic board:
3 x 470uf 16v
12x 10uf 25v
5x 100uf 16v

power board:
2x 1000uf 35v
2x 680uf 25v
4x 10uf 50v
1x 33uf 35v
2x 1000uf 16v
1x 100uf 16v
1x 220uf 10v
1x 220uf 25v

and here is the digikey cart sharing (i think this will work)
http://www.digikey.com/short/7rb0vr

Is everything in the digikey cart accurate?

thanks

Lucky you. That's the easier one to repair. Try replacing the 3 caps circled in red. Feel free to change any circled in blue if you want. But the 3 circled in red are usually the problem.

Make sure to pull straight out on the cap when desoldering. I have seen some botched repairs where the person pushed back in a little on the cap, and lifted the thin copper trace and pad. Those pads lift easily if you push on the cap.

Hi Lumberjack777,

I've got the same boards as BtB and same list of Caps to buy. Since I've got the ones that are "harder to repair." Should I just replace them all or are there a few suspect caps on these other versions?

BtB, did you manage to fix your Hanns by replacing all the caps listed?

Thanks!

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

No problems .

Let us know if you ever get problems with the monitor again.
Although, if you used genuine Panasonic caps on the logic and power supply boards, this monitor should make it at least 5 more years of trouble-free operation.

[feil]

Re: Hanns-G HG281D, LCD Monitor no power

i have now replaced them too, and for now its working.
i also have added two 40mm fans so thaht they can blow some air up in there^^
i hope that his now working for longer than 1 month^^

thanks @ all for your help.

regards
clemens

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

^ Yes, the caps on the logic board need to be replaced too. They run really hot next to those linear regulators, and if they are not a good brand, they can die quickly.

[feil]

Re: Hanns-G HG281D, LCD Monitor no power

now i have changed the caps on the power supply with panasonic caps, but after some minutes it also gos dark, and makes noises^^

could it also be some caps on the logic board? because i have changed there some too,
and i also could try to change the caps on the inverter.
and if i turn it off and on, it works for abaout 30seconds to 1 minute then dark again

[feil]

Re: Hanns-G HG281D, LCD Monitor no power

i have now orderd some panasonic caps, and i change them when tehy are here and tell you if it has worked.
thanks so far for the help.

[Wester547]

Re: Hanns-G HG281D, LCD Monitor no power

^ May want to avoid egekecu as well, based on this:

http://www.ebay.com/itm/12-Pcs-Nichi...item439b7f07ef

I think those Teapo are actually resleeved G-Luxon with that X-shaped vent. G-Luxon aren't very good either, though...

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

@ feil: Yageo = Teapo, and Teapo are quite unreliable, especially in hot environments.

Sat receivers and set-top boxes usually don't run as hot as LCD monitors, so that's why those Jamicon and Yageo caps may work fine there. But this particular monitor (HG281D) is known to run hot, so I would recommend you do it with high-quality Japanese caps. Panasonic FM and FR are common online, among other brands. Probably best to avoid eBay auctions with sellers from China and HK, except for seller egekecu.

[feil]

Re: Hanns-G HG281D, LCD Monitor no power

What brand and series of capacitors did you use for the recap. I see some new caps on the power board that I cannot identify as one of the known good Japanese brands. If you used cheap caps, it is possible that this could be the cause of your problem again, even though the symptoms are different.

hello. most of them are jamicon caps, und some yaego.
i had the jamicon before in other satelitte receiver and no probs with them.

[momaka]

Re: Hanns-G HG281D, LCD Monitor no power

i have also one of the hg218d become from a friend, that was not working anymore.
i have changed all the caps on the power board and all the 470uf 16V and 100uf 16V on the logic board.

the monitor was fine working now for about 1 months and now i have the problem that hes running about 10 minutes and then he screen goes dark,
after it has cooled off, it also works for about 10 minutes and then the screen goes dark.

What brand and series of capacitors did you use for the recap. I see some new caps on the power board that I cannot identify as one of the known good Japanese brands. If you used cheap caps, it is possible that this could be the cause of your problem again, even though the symptoms are different.

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

I'd have to take the monitor apart. I just have the back cover off. Sorry.

If you can, try and trace the 3.3v and 4.8 circuit back and see what components (or caps) are in that circuit. I'm really not an expert in circuits. Maybe an expert like budm or another can help you trace that.

Until then, I'd check for faulty solder connections. Sometimes they will last for a few weeks or a month and then give out if they are faulty.

[feil]

Re: Hanns-G HG281D, LCD Monitor no power

hello
i get the 24Volts, but im missing the 3,3 and 4,8V and from whats on the inverterboard stands, i think thats to start the inverter board.
so something on the power supply , a bad cap maybe? i have changed all of them and it was working for about 1 months.

do you maybe now what caps are for the 3,3 or 4,8 volt ?

thanks for your help.

[Lumberjack777]

Re: Hanns-G HG281D, LCD Monitor no power

Hello.
yes you see the screen and windows desktop, so inverter or lamps, should i try a new inverter board?

it would cost me about 35 dollar. or only the caps on the inverter board?

and lamps changing is that even possible?
and thanks

Before you buy a new inverter board; you need to test and make sure it's getting the proper voltages.

Unplug the plastic connector to the inverter board. Then turn on the monitor (make sure you have video input attached). The connector has 12 holes. Using a digital multimeter test the voltages inside the connector. I have small pins soldered to my dmm leads so they fit inside. Place the black (negative) lead on a screw on the frame. And put the red (positive) lead in each of the holes. Here's my readings, with brown wire on the left side; black wire on the right side.
3.3v, 4.8v, 0v, 0v, 0v ,0v, 0v ,24.2v ,24.2v, 24.2v, 24.2v, 24.2v

The important thing is that it's getting 24 volts on those a 5 connections.

If you are getting the proper voltages to the inverter I'd probably try a cheap repair first. It's good practice.

If a lamp was bad, you'd at least get some sort of flash on the screen before the monitor shut down due to a faulty lamp (2 seconds to black)