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 Sanyo CTP 8632, 79P chassis problem
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 Return to top of page · Post #: 1 · Written at 9:27:52 AM on 22 November 2013.
JeffT's Gravatar
 JeffT
 Location: Albury, NSW
 Member since 14 April 2013
 Member #: 1328
 Postcount: 15

Hi All,

I have the 79P chassis. It was working great when I got it recently. After a short while of use, the set stopped working. It seems it is getting no power. The 4 main ceramic resistors, R900 to R903 get incredibly hot.

I have not had the chance to look further into it. Hopefully it is simple.

Thanks,

JT - I have a schematic if required
 
 Return to top of page · Post #: 2 · Written at 1:41:31 PM on 22 November 2013.
Marcc's avatar
 Marcc
 Location: Wangaratta, VIC
 Member since 21 February 2009
 Member #: 438
 Postcount: 5389

Circuit would be desirable as the masses are likely not at all familiar with it & Rxx does not mean a lot to me unless I can see where it is in the scheme of things.

Marc
 
 Return to top of page · Post #: 3 · Written at 10:04:27 PM on 25 November 2013.
TV Collector's Gravatar
 TV Collector
 Location: Ballarat, VIC
 Member since 4 January 2011
 Member #: 803
 Postcount: 456

R900 to R903 are high wattage resistors and will run quite hot normally. You'll need to do some voltage checks around the power supply main regulating transistors to see what is going on.
The power supply is a fairly conventional linear type with two power transistors in parallel as the main pass transistors. They are driven by a custom Sanyo voltage regulator IC.

A word of warning: The transistors have around 240v DC on them so work safely!
 
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