Hi, this is just going to be a quick follow-up on this Samsung
plasma TV, because I wanted to test
a few more things, didn't have enough time last time. So we'll check this sucker out
shall we? See if we can at least get an external
signal working. So let's give it a go. Now the problem last time
was that none of the
analogey type inputs worked at all.
The component video didn't work, the SVideo didn't work, the VGA didn't work,
and-- but I didn't try the HDMI. So I'm going to try the HDMI
and-- now. Also a lot of people
suggested it might be something incredibly simple that was just due to
the blue screen mode that I had turned on. So we'll disable
that, and we'll give it a go. Now, I've got the thing
plugged in now. Now this one-- this board is completely
safe to touch because it is isolated from the
mains supply. And you'll notice that they have a high-voltage warning sticker
up here, that is for the rest of all of the circuitry which we saw last time
under there. That's all the high-voltage stuff, you do not want to go
poking around in that. But all this-- all low voltage 3.5
volt, 5 volt stuff, all mains isolated. So it's completely
safe. So that's why they have the warning sticker on this part, and then a separate removable
panel on here. It just allows servicing and
repair on just the completely safe side of the thing.
That's just a little safety aside there. Now I've got this thing turned
on and it is actually powered up, and if I do the old back-of-the-finger
test, that chip there is
getting quite warm. Let's zoom in on that.
That's the old back-of-the-finger test. This one is--
yow! Hot, hot, burney, burney, burney.
Whoa, that's the-- the main Samsung BGA
part there. That's just the memory there. That's
another-- some sort of video processor. A little bit warm, that's
the HDMI panel link. That's doing nothing.
That's a little bit warm. This one's here, not a problem. So we're just searching
for any parts that are particularly hot. Now this one, a few people
commented that it looked like it may have been burnt out. So we'll take a
closer look at that under the
times ten macro lens. But it's-- it's warm, so it's powered up.
But it's certainly not-- it's getting warmer, warmer, warmer.
So I don't know if that's normal for that device, we'll have to check the datasheet.
Ooh, that one's-- that one's pretty hot.
Geeze. We'll have to check out what that one is.
And the others... not really a problem.
So let's take a close-up look at that one. As I note in the previous video it seems to be
the decoder for all of the analog inputs down here,
the component, the SVideo, the RGB, and all that sort of stuff. Because all
of these AC coupling caps down here and you can just
see all the traces flow from there into there, and possibly this
chipset down here as well. But that one we're interested in, so
let's take a look at the datasheet for that one. I couldn't get the precise
Philips datasheet, but I did get a second source
one here from Trident Semiconductor. And no surprises
it's a 10-bit video decoder with comb filter and
component video. 4 studio-quality ADCs, 16
analog inputs. And I can link this in
to the notes down there but it's, you know, it's got all sorts of--
it's got the composite video input, it's got the RGB inputs, it's got the
component inputs, and everything you'd expect. All that-- all those
inputs which aren't working. So it's-- you know,
a fair guess that that chip-- that there's something
wrong with that chip in there. Because we know that all the video processing around
here all works, because it's driving the panel just fine. So
rather than troubleshoot that right now, first thing I'm going to do is
by-- essentially bypass that chip by not using the analog inputs but using
the digital HDMI input that'll go through the separate
HDMI processor here, and
presumably directly into the processor
up there. So let's plug in HDMI, see if it works.
Alright, here we go. Plugged it into my notebook down
here before, HDMI. And as before we've got that blue screen
we'll switch that off in a minute. But let's
change our source down here. You ready?
Tada! There you go.
It works a treat! As expected, HDMI
works fine. Now we'll still cha-- check that blue
screen thing to make sure that's not an issue. But there we go, we bypassed
that video-- analog video decoder chip,
and went straight through the HDMI. And that is
perfect! I mean there's no dead pixels, there's nothing, it doesn't
quite go right to the edge down there, but that--
that is beautiful. That works just fine, I love it.
Let's play a video on here, see if the audio and everything works.
[ audio from EEVblog playing on TV ] Tada! There you go! Working
a treat. And the audio's-- as you can hear, is coming through
the TV no problems. Beautiful. We have a winner
folks. Check it out.
[ audio from EEVblog playing on TV ]
Okay, I've turned off the blue
screen mode and no, the PC input does not work and
yes, I've set it to the resolution possible, 800x600.
If it can't do that, seriously it does not work. So the VGA input
is definitely cactus. But folks, woohoo!
Check this out. I am getting something on the composite video
input now. I've got one of these VGA to composite
converter box-- boxes which is generating the colour bars there,
but it's-- it's flickering. Check that out. So
I don't know whether or not that's normal, I haven't used this box before.
But it-- yeah, I don't know whether or not that's the
TV or the box outputting something. But I can't seem to make it,
you know, stable or anything like that. So I don't know if
that's a fault with the TV or the generator box.
Nope, bluescreen mode's on. So there you go, I'm-- so it wasn't that.
So I'm not sure why it suddenly decided to work. This is the same box I was
using yesterday to test this thing. So
I don't know what the deal is there. But composite is working
so that means that chipset is actually processing something.
At the very least-- I mean, it can't do that, there's a lot of complexity involved
in doing that. It's not like a-- I don't think part of the chip's going to fail with
the VGA input. So not entirely sure
what the issue is. And what do you know? It does actually work
a treat. So it was that box generating a non-compatible
composite signal in some way. I've got it now hooked up to a
old DVD player with the composite output, and it's working a
treat! So I don't know why that wasn't working the other day.
The thing has suddenly decided to work. Did I actually press on the chip or do
something weird like that? It is one of those BGA chips, so
you know, I-- presumably
I can only think that I did actually make the chip come good.
Maybe it does have a dry joint on one of the balls
underneath the BGA or something like that. Maybe we can try some freezer spray. So what I'm
going to do now is freeze this BGA chip to see if it does anything. Don't have
any freezer spray here in the lab, but the next best thing: air duster.
You've seen this before, just turn it upside down, instant...
[ alarmed sound ] freezer spray. Let's go, let's see if I can get in here.
Here we go, I'm going to hit that
BGA chip and see what happens.
[ sound of spraying ] Nope. Chip's going all
frosty. I've got Frosty the Snowman on that BGA
chip and it's holding in just fine. Not a problem.
And if you want to have a look, it's still cold.
Here we go. Aww no, it was.
[ chuckles ] It was cold for a second there. But this is what it looks like when you freeze
it. [ spraying sound ] You get all the frost on the chip, like that.
And there you go, it's nice and cold.
And it's still working. And just to show you that
blue screen mode. You can see there's no signal, it's turned off.
Disconnected, it's got the blue screen there.
And you switch it on and it just automatically should...
hello? There we go. Automatically
switch-- there you go look! We've got some-- check-- check that out.
That is not a clean signal anymore. So
what's going on there, it was before. You saw it before,
it was absolutely perfect. Now we've got this colour--
there's some sort of colour tearing across there. I'm not sure what the correct term for that is.
But you can see it. Hopefully you can see that-- yeah you can definitely see that on the
screen. There's that colour tearing on the display
across here and down here as well. So I'm not--
there is something wrong with this thing. But it seems
intermittent. So at least we got the thing going, I'm not
entirely sure why. Maybe I'll hit it with some more freezer spray
and see what happens. [ spraying sound ]
Nope. Let's try... [ spraying sound ]
In the general vicinity.
[ spraying sound ] Like the electrolytic caps and
stuff like that. No, no, it's still
got some tearing on there. So there you go.
That is very interesting.
If you've got any good ideas about what's possibly going on there, then--
oop, no, it was good there for a second then--
then it's going it again. So if you've got any idea what's going on
there-- I mean ch-- clearly the decoder chipset is working
just fine, because you wouldn't get that unless, you know, as I said,
you can't get like a partial failure on that chip or anything like that. That's,
you know, really not feasible at all.
Whew! Your guess is as good as mine.
So this is one sick puppy here. Let's plug the HDMI
back in. And does it auto-detect?
No, doesn't auto-detect, but I can switch the source there.
And there we go. Nothing wrong with the HDMI. So
yeah, I don't know. Something's intermittent on this sucker,
and-- but the HDMI works fine. Which makes this a very-- still a very
usable set. I mean you use-- ideally you want to be
using the HDMI input for the best quality anyways.
So, it's a winner as far as that works. The audio and video
absolutely first class for this, what, 8 year old
plasma display. 2005 model.
And-- which according to people complaining on the web, this
particular model has very high failure rate and was very expensive
to repair after the warranty period. Which was presumably like 12
months for your standard warranty unless you got one of those extended warranty things.
And no the component video is not working either. I'm generating
my component signal. It's actually detecting that there's component
input there, and it's enabling that particular channel when you
cycle through the source here, but I've got a
component device which is generating component out, and
zip. Now there are a few people who suggested that
this Philips SAA7119
video decoder chip looked a bit burnt or something like that.
It had some physical damage, and I've got to admit, I can actually see
sort of the shape of the die underneath
it, but it doesn't get that hot. And of course it's working
as we saw. It's at least doing something. So there's certainly no
physical damage to the chip. And yeah, it does look a bit
sort of thermally stressed I guess you could say, but
I think that's just a natural part of the--
this particular package anyway. So, I mean clearly there's nothing
physically wrong with it, because it does actually work. Now Trevor from the
television mag forum, he commented that I should probably do a
service-- factory reset mode in the service menu on this thing. But
I don't have the service cable that plugs in the back of it, couldn't be bothered making
one up, don't know how it works. And from what I'm reading you can
enter the service mode via the remote control. So I don't have a remote for it.
We'll probably go out and get a remote now because it
does seem to work, it seems to be useful. At least certainly in the HDMI
mode, not a problem. So if you've got any
ideas what's actually going on with this sucker, I'm sure it's something
to do with that chipset-- that main decoder chipset. But the
freezer spray didn't seem to do anything. Bit surprised by that. I expected
something to happen there I guess, there was a good chance of that. But
I don't know. I need a remote to enter-- do the factory reset,
maybe that'll help, maybe there's nothing physically hardware wrong with it, maybe it just needs
a factory reset. You know, the I2C codes going to that decoder
chip or something, to reset it. Eh, who knows. Anyway,
I think it's an absolute winner. Beauty. I'm going to--
not sure what I'm going to do with it. I don't have a stand, so I can't just take it home and whack it in the lounge room
or replace my other one. So it's either try and get a stand
for it or mount it on a wall somewhere. Could even mount it on the wall
here in the lab perhaps. Well the bloody thing weighs 50 kilos, so mounting it
on one of these gyprock walls, eh, I don't know. And I've had a few
people comment, do I always have bare feet around the lab. Do I always work in bare feet?
Yeah, pretty much. It's much more comfortable. But occasionally I do
wear Australian safety boots. Pair of thongs. Beauty.
[ sparking sound ] captioned by sen