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 Suitable replacement for PTC thermistor?
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 Return to top of page · Post #: 1 · Written at 12:23:38 AM on 25 April 2013.
Chris Ronayne's avatar
 Location: Wauchope, NSW
 Member since 1 January 2013
 Member #: 1269
 Postcount: 576

Hi all,

I am repairing a 1996 20" SAMSUNG TV-516 colour television set (unsure of chassis). This set appears to have been water damaged at some time, but was still working great, until I switched it on yesterday. I was greeted by a bright green flash inside the set, which then shut down. I looked inside and discovered that a PTC thermistor (P801) has fried itself, taking the 250V 3.15A fuse with it.

I don't know a great deal about posistors, other than their use in the degaussing circuit, and so can't interpret the markings on the top - 14MS 03H4. I have a few spare PTC thermistors kicking around in my workshop, marked as follows:

M7 MZ73-18ΩM
14MQ 03L5
T2 Mz73B-18ΩM
120M 3003
07MX KDM61
A9R0Q 6N

Would any of these be a suitable replacement? If not, where could I look to find one? I've done a quick search, which yielded very little in return.

There is also a small four leg transformer (line filter?) or inductor (it's marked as L801) in the degaussing circuit, so would it be a suspect component?

Cheers,

Chris


 
 Return to top of page · Post #: 2 · Written at 8:29:03 AM on 29 April 2013.
Wa2ise's avatar
 Location: Oradell, US
 Member since 2 April 2010
 Member #: 643
 Postcount: 830

I'd check to see if something else in the set failed, causing the thermistor to die and the fuse to blow. Like a shorted horizontal output transistor or flyback. Or a bad electrolytic.

As for a thermistor, you could probably be able to use one pulled out of an old PC computer power supply. The power loads are similar.


 
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