Weird DVD Problem

[ThermalRunaway]

I wonder if anyone can offer some sanity saving tips on this one. I've got a DVD Player which, for some reason, has suddenly decided to output only in black&white.

My first thought was that someone had been fiddling with the remote and stuck it in the wrong mode or something but it's not in NTSC or SVHS or any of those alien modes (alien to my current setup anyway). The effect seen on the screen is a black&white picture with some visible patterning and some expanding rings. The effect is similar to that seen when you try to view an SVHS output on a standard video screen. This effect is seen from the SCART output as well as the composite video output. There is also a button on the controller called "picture mode" which takes you through a few useless gimmicks to add different effects to the picture. One of the picture modes is actually "black&white", and if I select this mode the picture stays in the black&white mode, but the previously visible patterning dissapears leaving a crystal clear, b&w picture. This would seem to suggest a problem with the colour processing somewhere.

I've stuck my scope probe directly on the composite output port and played back a home-made ColourBar DVD. Strangely, the video output looks completely normal - I've got colour burst, I've got the familiar bands of colour information that you would expect to see when displaying colour bars, and all the amplitudes and periods seem to be correct. With all that in mind, I'd have expected to have seen some colour on the screen, even if that colour information was wrong in some way

My next suspect was the colour burst. I decided that if the colour burst frequency was off, perhaps the television wouldn't display the colour properly anymore. I've managed to crank my scope down so that I can view the colour burst properly. 10 cycles at 4.43Mhz. So even the colour burst is right!!! I can't say whether the phase of the colour burst is correct, and I would think it'd be incredibly difficult to confirm that.

Any bright ideas? If I had an older television I'd consider bypassing the colour killer to see if it brought colour to the screen, but that's not such an easy trick these days.

Brian

 

[Nigel Goodwin]

The colour subcarrier for PAL is 4.43361875MHz, NOT just 4.433MHz, and it HAS to be that accurate, and is actually phase locked to the incoming burst to ensure it.

So checking on a scope isn't much help!.

It sounds most likely that your DVD is outputting NTSC rather than PAL?, which would cause no colour. Some DVD's have settings for PAL and NTSC, some have an Automatic setting, I would try searching the menus. Are you not able to use it via RGB?, where there's no colour involved!, and gives the best possible picture.

 

[Roff]

Does your TV display colour from other sources? I'm assuming that's the case, but I don't believe you said that explicitly.

 

[Dean Huster]

At least your DVD player does SOMETHING. I buy a DVD player and it quits on me -- completely dead, not responding to any pushbuttons, whether front panel or remote.

Now the second one I've bought is dead.

Long live VHS!!!

(I used to say, "Long live Beta!")


Dean

 

[ThermalRunaway]

The DVD Player definately is not outputting NTSC. For one, it's clearly set to PAL in the menu. Two, the colour burst frequency suggests a PAL signal and three, my TV is capable of displaying NTSC and if I set my TV to this mode, colour is still not displayed.

I'm not able to set the player to RGB as there doesn't appear to be any settings for switching between RGB and Composite Video (which is peculiar I know)

I wonder if the IC which handles PAL encoding is faulty. Strange fault symptom though.

Brian

 

[Roff]

Does your TV display colour from other sources? I'm assuming that's the case, but I don't believe you said that explicitly.

Paraphrase: Are you sure your TV is working properly?
ThermalRunaway, should we assume you thought this was a stupid question?

 

[Someone Electro]

Cod it be a firmware problem?

An DVD player in scholl did somting starnge.We put in the DVD and then wen you tryed to play it it displayed some paterns and it stoped responding.All we cod do is pull out the cord and try agen.In the socond try it worked.

So meaby the firmware mesd up some prety delecate setings.

I dont have an DVD player.I use my PC

 

[ThermalRunaway]

RonH - I've confirmed that the TV is working by trying the DVD Player on another where it exhibits the same fault symptoms.

SomeoneElectro - I've actually downloaded new firmware off the internet and updated the player with the latest version, but the fault still remains.

Brian

 

[Someone Electro]

Was there a storm or somting? Or did it get some force like bumping or slaming.So that an weak solder came lose or somting.

An stange thing whith a storm hapend to my dad.His PC was off and i was using my PC during a storm.Wen he tryed to boot-up his PC It didnt find not a single thing conected to the IDE bus(Thats where the hard drive was).We did evryting posible in BIOS but noting worked.He tock it to the computer store for them to fix it.Yep somting on the motherboard went bye bye.The guy also told dad that the dard drive is behaving a litle stange.And after a weak the harddrive realy went bye bye too.(and all the data that was on it)

No other pece of electronics in the house was dameged.

 

[Nigel Goodwin]

Was there a storm or somting? Or did it get some force like bumping or slaming.So that an weak solder came lose or somting.

An stange thing whith a storm hapend to my dad.His PC was off and i was using my PC during a storm.Wen he tryed to boot-up his PC It didnt find not a single thing conected to the IDE bus(Thats where the hard drive was).We did evryting posible in BIOS but noting worked.He tock it to the computer store for them to fix it.Yep somting on the motherboard went bye bye.The guy also told dad that the dard drive is behaving a litle stange.And after a weak the harddrive realy went bye bye too.(and all the data that was on it)

Was a modem lead plugged in?, if so it's probably lightning up the phone line! - a VERY common cause of damage!.

 

[Someone Electro]

yea but it probobly wodnt get that far.

First it goes trough an ISDN-ADSL spliter then in the ADSL modem,then in the router and then finaly in the PC.(There is also the interface box and the wierles ISDN station on it)

If it was that it wod probobly fry somting along the way.

And my PC is conected to the same router.

He alsomst didnt get insirance for it since the isuramce guys ware like: "If it was overvoltage why ididnt it fry the PSU then?"

He now instaled overvoltage protection for the PC,modem,ISDN and router.

 

[SkinnyBoy]

our TV was showing very wrong colours with the DVD player, but the VCR worked fine...

the DVD player also worked fine on another TV...

there was a "tint" control on the front of the TV that just have been turned slightly... adjusting it made the DVD colour correct, and the VCR was still correct..

 

[ThermalRunaway]

With regard to the lightning down the phone line post, it doesn't matter what you've got in front of it, the damage can cascade on through a number of devices, leaving a trail of destruction in it's path. As Nigel says, phone line problems during electric storms are extremely common. The amount of Sky Boxes we get back with lightning damage after a storm is unreal.

Brian

 

[Someone Electro]

Thats waht im teling you! Non of the other devices ware dameged.The spliter,the modem,the router and the phone worked normaly.I was on the internet.

The last time lightnig struck in the wiering was in 2000.It fryed TVs,VCRs,phones... all over the vilage.In our house the only thing it has ben burned is an 1 amp fuse.It was just sudenly a realy loud bang and all the lights went out sinnce the main circuit breaker triped.So i went to flip it back on (wile almost faling down the stairs).And evrything worked.then tomorw i heard what damege it did at some houses.
We didnt have any lighting protection.

 

[Someone Electro]

Oh and the lighting (the one that bustaed dads PC) was REALY close.I cod hear the lighting in my PC speakers.It sounded like scratching.
It was qite a scene to watch.Lightning struch about evry 3-6 seconds.(somtines you cod see the arc realy clear)

 

[ThermalRunaway]

I guess that's what you mean in your signature strip when you talk about a shocking experience

Brian