41GR8840 Blows Fuses

I have a Philips 41GR8840 rear projection TV which blows the main
circuit board fuse instantly (even when the unit is in standby
mode)Leading up to this problem it used to make a funny crackling
noise. I dao't have a circuit diagram and feel like I'm fumbling in the
dark a bit. Can anyone shed any light as to the possible problem?

Thanks

Dave

 

[Craig Hart]

there's a short somewhere in the unit.


<dgliddell@aapt.net.au> wrote in message
news:1119263001.298355.226510@g44g2000cwa.googlegroups.com...

I have a Philips 41GR8840 rear projection TV which blows the main
circuit board fuse instantly (even when the unit is in standby
mode)Leading up to this problem it used to make a funny crackling
noise. I dao't have a circuit diagram and feel like I'm fumbling in the
dark a bit. Can anyone shed any light as to the possible problem?

Thanks

Dave

 

[Joerg]

Hello Craig,

there's a short somewhere in the unit.

Or maybe a capacitor on the verge of failing.

Regards, Joerg

http://www.analogconsultants.com

 

It just blows with the wire melted. I have disconnected the leads off
to other parts to the unit (eg EHT) therefore isolating the power
supply section. The result is the fuse blowing just the same.

 

[Phil Allison]

<dgliddell@aapt.net.au

It just blows with the wire melted.

** You do realise the fuse MUST be a "slow blow" type ????

I have disconnected the leads off
to other parts to the unit (eg EHT) therefore isolating the power
supply section. The result is the fuse blowing just the same.

** See above - a standard (plain wire) fuse will blow at EVERY switch
on due to the massive surge drawn by the de-gaussing coil.






............. Phil

 

[Matt2 - Amstereo]

 

[Mark Harriss]

dgliddell@aapt.net.au wrote:

I have a Philips 41GR8840 rear projection TV which blows the main
circuit board fuse instantly (even when the unit is in standby
mode)Leading up to this problem it used to make a funny crackling
noise. I dao't have a circuit diagram and feel like I'm fumbling in the
dark a bit. Can anyone shed any light as to the possible problem?

Thanks

Dave

Does it just blow with the wire melted or is it
an almighty bang with the fuse glass shattered
and blackened on the inside?.

 

[Mark Harriss]

Phil Allison wrote:

dgliddell@aapt.net.au

It just blows with the wire melted.



** You do realise the fuse MUST be a "slow blow" type ????



I have disconnected the leads off
to other parts to the unit (eg EHT) therefore isolating the power
supply section. The result is the fuse blowing just the same.



** See above - a standard (plain wire) fuse will blow at EVERY switch
on due to the massive surge drawn by the de-gaussing coil.






............ Phil

Does the original fuse have a little spring inside
or blobs of solder-like metal on the wire?.

 

[Mark Harriss]

Do rear projection TV's have a degaussing coil Phil?,
I've never seen the inside of one.

 

[valiumboy]

I was just about to ask the same question.The main fuse should be a slow
blow type.
Primary power supply fault, bridge rectifier?, main filtering cap? chopper
transistor?


"Mark Harriss" <billy@blartco.co.uk> wrote in message
news:42b7ebbf$0$271$61c65585@uq-127creek-reader-03.brisbane.pipenetworks.com.au...

Do rear projection TV's have a degaussing coil Phil?,
I've never seen the inside of one.