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Looking for schematic diagram/service manual of Toshiba Combi TV/DVD

Terry Doyle

May 15, 2015
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Hi All,

I have a Toshiba Combi TV/DVD (model no. 22DL502B) and have been having some issues. The TV was working fine for some time until it one day simply switched off of it's own accord. I tried replacing the fuse and had no luck, I also cracked it open so to speak and had a look inside, but couldn't find the source of the problem.

I have been unable to find a schematic diagram or a service manual anywhere online. I even contacted Toshiba directly and they were no help at all. If anyone has access to one themselves, or is aware of any similar common problems, it would be appreciated if you could point me in the right direction! I was a TV engineer myself in the past before integrated circuits became a bit more common so i should be able to fix it with a nudge in the right direction.

Cheers
Terry
 

Anon_LG

Jun 24, 2014
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Provide picture/s of the internal PCB (these must be of high quality, any text must be readable). Provide pictures of both the front and back of the PCB.
 

Terry Doyle

May 15, 2015
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May 15, 2015
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Here is the front and back of the PCB. Hope these are detailed enough, let me know if any more are needed.

20150520_183821.jpg 20150520_184629.jpg

Cheers,
Terry
 

Anon_LG

Jun 24, 2014
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Firstly, beware of the those capacitors (the long black cylinders), it is very unlikely however they could be charged with very high voltages, take care when touching them. I have looked over the board thoroughly and can not find any visible surface damage, which may make fixing your board rather difficult, amongst other things, the capacitors could be damaged internally, the IC (8 pin DIP package) could have fried or one of the resistors could have blown and pinged off.

I suggest that you look very carefully at the components, here is what you are looking for:

Capacitors: (Either a long black cylinder or a two terminal domed component) Look for bulging or any kind of leaking, with the cylinders check the ends, if there are crystals or liquid at the end it is likely that the capacitors has broken.

Resistors/surface mount capacitors: Check for scorch marks or cracking.

Inductors: (coils of wire) Check that the wire has not split anywhere.

Because the visible damage is so minute you will have to check this yourself before I can help you further, if absolutely no visible damage is present you may have to buy a new board. But let us hope it will not come to that, I will do what I can.

Hope this helps,
 

Terry Doyle

May 15, 2015
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Hi to everyone at Electronic Point.
As I have already stated, I am a retired tv engineer so I do know about testing electronic components.
If I could obtain schematics for the board shown, I could check out the board in a logical way using a multimeter.
I don't want to take components out of circuit unless I think they are faulty. I am awaiting delivery of an ESR meter
so that I can check the capacitors in circuit. I don't have an oscilloscope so I can't check for correct waveforms at appropriate test points. Pity really!

I do desperately need access to the schematics for this power board as I would like to fault find it down to component level and not change the board.
So if anyone out there has access to the schematic, I would be very grateful If I could obtain a copy.
I hope everything goes well for electronic projects that you guys are involved with.
I will keep everyone posted as to how I get on.
 
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Anon_LG

Jun 24, 2014
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Sorry, I forgot that you were a TV repair engineer. :oops:

Good luck with the repair, I doubt I can provide any relevant help that is of higher level than what you know.
 

Terry Doyle

May 15, 2015
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Thanks for trying to help anyway. I would just like to make a comment here.Toshiba's public relations department is really appalling.
I emailed Toshiba informing them that I needed the circuit diagram and service manual for a Toshiba 22inch combi tv/dvd model number22DL502B. I also informed them I was a former tv engineer. They emailed me back saying that they could not help.
Don't they have trained service engineers or circuit diagrams for their equipment?? Instead they gave an email list of engineers who would answer a fault finding question by email but would charge £16.00p!!. If you had to ask 10 questions before the fault was found,
you would have to pay out £160.00p!! In that case, why don't I just buy a perfectly good second hand set of Ebay for £90.00p.
They also gave me the phone number of the local Toshiba repair specialist who quoted £25.00p just to look at the set.
I have searched various web sites and although there are links to schematics for hundreds of Toshiba tv models, for some unknown reason, there seems to be no schematics available for this particular model.
So once again, If anyone has a copy or a link to a website where I can obtain this particular schematic, please email me.
 
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Martaine2005

May 12, 2015
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Hi Terry,
This is an old'ish' thread. But if you are retired, did you have components like the red/brown cylinder type thing in the top left of your picture?

Martin
 

Tha fios agaibh

Aug 11, 2014
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did you have components like the red/brown cylinder type thing in the top left of your picture?
Martin

Looks like a sm fuse.

Finding schematics is often fruitless these days. Even if you find one, its probably an obscure /obsolete microcontroller that has failed.

Gee I miss the 70's when everything was discrete components.
 

Martaine2005

May 12, 2015
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Looks like a sm fuse.

Finding schematics is often fruitless these days. Even if you find one, its probably an obscure /obsolete microcontroller that has failed.

Gee I miss the 70's when everything was discrete components.
Indeed, that's why I asked if he knew what it was!
I saw straight away it was a fuse.
But I wasn't sure if he would know due to being retired!.
Do you know when these fuses were introduced?

Martin
 

Martaine2005

May 12, 2015
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For all I know, he retired last week.
Lol.
So, So true. Maybe he is Greek and retired at 20, ten years ago!! Who knows..
BTW, I have seriously been 'googling' each word of your forum name! Please explain what it means..Ta

Martin
 

Tha fios agaibh

Aug 11, 2014
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Tha fios agam is Scottish Gaelic (similar to Irish Gaelic) meaning:
"I know" or "I get it"
literal translation would be;
The understanding at me.

But feel free to call me John.
 

Martaine2005

May 12, 2015
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Tha fios agam is Scottish Gaelic (similar to Irish Gaelic) meaning:
"I know" or "I get it"
literal translation would be;
The understanding at me.

But feel free to call me John.
Thanks, Hi John.
So I was kind of close with Celtic?
 

Tha fios agaibh

Aug 11, 2014
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Yes its a Celtic language, but so is Irish, Welsh, Manx and I believe a few others.

How about Martaine, Martin?
 

Martaine2005

May 12, 2015
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Yes its a Celtic language, but so is Irish, Welsh, Manx and I believe a few others.

How about Martaine, Martin?
Hi John, Oh that goes back to the 80s too.
I had a girlfriend called Elaine. My best mate 'Irish' called me 'martaine ever since. It was a way we could talk about Elaine without my 'then' current girlfriend knowing. It's just something easy to remember.
Nothing more and nothing less. Although my mate 'Irish' still phones the house and says 'can I speak to Martaine please'. Just an old between 'us' joke...

Martin
 
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