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Electronics => Repair => Topic started by: urbis on January 07, 2015, 10:17:42 am

Title: Toshiba 46ZF355D - Dead
Post by: urbis on January 07, 2015, 10:17:42 am
Hello,

I bought this TV as faulty, apparently not powering up.

I've not yet tried it, but took the back off, nothing seems visibly failed.

However, the one thing that amazed me was the sheer build quality of the thing - not only does it weigh around 17 metric tonnes (OK, perhaps slightly less), but seems built to a high standard.

Dedicated audio amp board, decent sized speakers, Rubycon main caps.

Some (poor) images below:

(http://i61.tinypic.com/ht8z2g.jpg)

(http://i57.tinypic.com/2ly34ty.jpg)

(http://i57.tinypic.com/21kbb7c.jpg)

(http://i61.tinypic.com/23wkv0i.jpg)

(http://i60.tinypic.com/208ea35.jpg)

Obviously, the first thing is going to be to clean everything up and start metering, but has anyone seen failures on this PSU before?

Cheers!
Title: Re: Toshiba 46ZF355D - Dead
Post by: tautech on January 07, 2015, 10:48:31 am
Quote
apparently not powering up
That doesn't give us much to run with.
Standby light?
Standby PSU running?
LCD backlight failed?
Any Audio?

If your nervous about plugging it in make a dim bulb tester with a bulb watt rating about the same or a bit more than the TV's rated wattage.
That'll allow you to power it without it going bang.
Title: Re: Toshiba 46ZF355D - Dead
Post by: urbis on January 07, 2015, 10:59:50 am
How does the dim bulb tester work?

Cheers!
Title: Re: Toshiba 46ZF355D - Dead
Post by: VK5RC on January 07, 2015, 11:12:54 am
If I am correct, you put an incandescent bulb in series with the mains input, the increasing resistance of the bulb as it takes more current means if the device is a dead short (and the bulb lights up) you won't blow too much stuff up!
If the device under test is ok the light bulb goes out.
Title: Re: Toshiba 46ZF355D - Dead
Post by: tautech on January 07, 2015, 11:18:07 am
If I am correct, you put an incandescent bulb in series with the mains input, the increasing resistance of the bulb as it takes more current means if the device is a dead short (and the bulb lights up) you won't blow too much stuff up!
If the device under test is ok the light bulb goes out.
Nearly right.
If the DUT is OK the bulb will glow dim.
Do some tests on working appliances to get a "feel" for it.
Google Dim Bulb Tester.