Samsung LE37R86BD HDMI trip on ac disturbs

[Dumah Brazorf]

Hi,
I don't know if the title is self explanatory. When using hdmi source both video e audio disappear for a couple of seconds when there's a fluctuation/disturb on the ac line like the start and stop of the fridge nearby (i think less then 10m on the ac line). VGA and others analogs have no problem. Didn't tested DVB-T.
I'm sure is not related with the source of the hdmi signal, i've tested with another monitor.
The tv is ~9-10 years old, i've already changed some caps on the 24V and 12V line of the power board. Excluding this issue the tv works properly.
Is there something I can do about it? Maybe replacing some filtering components on the hot side? The 105J cbb cap?

[petehall347]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

looks ready for new capacitors to me .

[CapLeaker]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

I see bad caps!

[diif]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

Yeah, I can see three swollen caps. So I'd replace the two next to the transformer and the four at the top at a minimum.
You don't say what capacitors you swapped yours for. Were they low esr bought from a reputable source ?

[Dumah Brazorf]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

I already swapped the caps you pointed. The board was already repaired years ago. The two caps at the bottom was replaced with ones that not fit properly, and other ones i can see because of the soldering.
It's hdmi related. I made a test in service menu with background of the hdmi input. Only the background was affected.

[diif]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

What caps are there now, "years ago" and they could have failed again.
Could be the two SMD caps next to the HDMI chip.

[Dumah Brazorf]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

The two at the bottom, the two at left, the rightmost 3 of the 5 at top. Btw I did not repair it the first time.
I changed the 3 obvious bulged and tested all the others with an esr meter and they're ok.
Maybe it's just my "noisy" old refrigerator? I hate smd caps...

[diif]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

Turn your fridge off for 5 minutes and try it.
Replacing those two aluminium caps on the mainboard is worth a try.
Grab with pliers from the top and give them a gentle twist left and right until the legs snap. The legs then unsolder easily.
Have you checked the caps on the hot side ?

[Dumah Brazorf]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

The fridge causes the 2 seconds hdmi black when its compressor starts and stops, not when is working or quiet.
Not checked hot side yet. It looks fine and the sistem works 99%.

[dskall]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

Maybe refrigerator causing noise. May need to install line filter.

[diif]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

Possibly a combination of both. The fridge putting out noise and the TV not filtering it well.

[tom66]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

It is due to a cheap HDMI cable with inadequate shielding, you just need a better HDMI cable, or just get used to it. Used to happen with the light switch in the bathroom for me.

[Dumah Brazorf]

Re: Samsung LE37R86BD HDMI trip on ac disturbs

The last test. Took a cord and powered the fridge to another outlet. No problem.
I'm good with this.
I don't have another hdmi cable at the moment.