Baird X47DTV power supply issues

[gilly1984]

Just bought one off ebay, seller says he doesnt know a lot about it but the screen looks good, Should hopefully be able to get it today.

Is there any known problems with these tvs Tom?

[tom66]

Re: Baird 47"

Known problem: They are a pile of rubbish :P.

Basically Baird is the brand BrightHouse use in the UK. BrightHouse are a financial services company masquerading as a retail shop. Everything on 30-40% credit. Buy a TV from there and it will cost you twice the actual price in the end and you'll end up with a piece of rubbish built by the lowest bidder.

Someone online did find out who made them, I believe it was a Chinese company at some point, under licence from about 20 different companies over the years (including Thomson I believe) which have sold the name of Mr. Baird and his original telivisor. So expect the lowest build quality although if it's quite old and 47" it may have a nice LG-Philips LCD panel in it, so there's something to like.

I have seen quite a few dead 47 inch Bairds before but never picked one up myself - always been outbid (or sold when I called) so I guess it is probably an easy fix known to those in the trade.

[gilly1984]

Re: Baird 47"

Cheers, I have paid £46 for it, here is a pic. doesnt look like one of the newer ones.

[tom66]

Re: Baird 47"

It -MAY- be a Proview chassis. The silver speaker style seems common to the older Proview sets. Only one way to find out and it involves a screwdriver and camera. I know Proview have a lot of bad cap issues...

£46 ain't bad I'd pay around that. Will see how difficult it is first!

[gilly1984]

Re: Baird 47"

Fingers crossed its fixable, will replace the £20 sony.

Hard to find these on google, but from what i have found it seems to be a x47dtv <<<Boring model number.

And it seems this is the psu.

Edit:

Seems there is 2 psus inside it?

[gilly1984]

Re: Baird 47"

Ok, i have the tv now,

Plugged it in and no lights no power no nothin.

Open it up and straight away notice a popped cap. (pic 1) 420v 180uf
Thought the big caps never go?

Then i noticed that there was a ribbon cable that links the 2 inverter board that was broken (pic 2), what is that for? Both inverters have there own power from the 2 power supplies.

Also both fuses have been blown, 1 in each psu.

Someone has been in it before as the brown and blue wires have been cut then reattached? See last pic.

Edit;
Yes, i know, my nails are manky.

There was a hole in the back casing, looks like they stuck summat inside and broke that ribbon cable.

[tom66]

Re: Baird 47"

You're gonna need to replace that ribbon as it will control the inverter.

Primary caps do go. It's false for people to say they don't. They fail less often but they do fail. And when they fail, they usually take out the PFC MOSFET and PFC diode.

Hopefully one supply is still OK, you can use it to make comparisons.

[gilly1984]

Re: Baird 47"

You're gonna need to replace that ribbon as it will control the inverter.

Primary caps do go. It's false for people to say they don't. They fail less often but they do fail. And when they fail, they usually take out the PFC MOSFET and PFC diode.

Hopefully one supply is still OK, you can use it to make comparisons.

In the process of mending it now.

Fuses on both were blown? And both fuses were different, one clear glass and one white, either both boards are bad, or whoever has been inside has swapped fuses about.

I dont think the psu with the blown cap has been removed before because there was a ceramic type cap bent over the screw, i had to bend it out of the way to remove the screw.

Also, it looks like summat has been spilt on the logic board as there is a stain, but it tastes like battery acid. Nothing leaking around it though. (Yes, i tasted it)

[tom66]

Re: Baird 47"

Check the bridge rectifiers and other power components on each psu.

[gilly1984]

Re: Baird 47"

Check the bridge rectifiers and other power components on each psu.

Can you point them out to me, still thick.

[gilly1984]

Re: Baird 47"

And just to add that the bad cap is not shorted. Dont know if that matters

[gilly1984]

Re: Baird 47"

bridge rectifier fine, it was hiding under that big heatsink.

[turbozutek]

Re: Baird 47"

The one I had was a re-badged Vestel (like almost everything cheap is these days) and only needed the solder on the PSU coils re-flowed to work perfectly. The joins all looked very good by eye, but one or more was clearly duff because after turning the iron on them with some good lead solder the TV was fine.

Vestel are a strange wee company who make stuff in Turkey. TV's, stereos, dishwashers, stuff like that.

http://www.avforums.com/forums/lcd-l...-watching.html

Chris...

[tom66]

Re: Baird 47"

Vestel are a strange wee company who make stuff in Turkey. TV's, stereos, dishwashers, stuff like that.

Not wee by any means though. 3rd largest TV manufacturer in the world!

[turbozutek]

Re: Baird 47"

Not wee by any means though. 3rd largest TV manufacturer in the world!

Yeah they own a bunch of what used to be regarded as "brand names" too. Goodmans / Grundig, stuff like that.

Anyway, the good news is that spares shouldn't be a problem. I found plenty of bits for the Baird TV I was working on, but didn't need anything in the end.

Chris...

[gilly1984]

Re: Baird 47"

Right, i moved the other psu into the place of the one with the bad cap, it must be the main one as more wires are on it, the tv now gives me a standby light, just need to get this broken psu fixed and this ribbon mended, very small wires in these gits.

This looks nothing like the vestels i have seen, cant even find the psu scematic?

[gilly1984]

Re: Baird 47"

When i press the power button the led blinks for a while then goes off, if i press the power button again when its off it goes back into stanby, constant blue light on.

Surely a good sign so far.

[gilly1984]

Re: Baird 47"

7 tiny wires later and the ribbon is fixed.

Checked each one for continuity and all check out on.

[gilly1984]

Re: Baird 47"

This tv has 2 power supplies that are the same.

One has gone.

The second psu is used only for the slave inverter, just wired the slave inverter up to the working psu and the tv came on, i was able to change inputs aswell , Now i just need to get this other psu going.

[gilly1984]

Re: Baird 47"

Just that second psu tom. With just one psu it cuts off after 10-15 seconds.

Pic included.