Re: KV-20EXR10 PS Problem

From: Jerry G. (jerryg50_at_hotmail.com)
Date: 10/12/04 

Date: Tue, 12 Oct 2004 15:17:45 -0400

Check for high ESR capacitors in the power supply. Be very critical
about the cap's ESR rating. If you suspect it to be defective in any
way, replace them.

Some of these caps are very critical, and if they are defective, the IC
may fail. These caps are doing various tasks such as being part of
circuits to control noise, pulse width, and filtering, just to be
simple.

I have had this type of fault, and had to replace a number of caps.

I have a Sony XBR that is going on 14 years old. It is used about 20 to
50 hours per week at times. I installed 2 fans inside of the cabinet. I
have one sucking out the air at the power supply, and the other blowing
the air down on to the horizontal output section. This set had only one
failure about 6 years ago, and it was the drive IC in the supply.
Instead of spending my time using the ESR meter, I replaced all the
caps, and then installed the two fans. I installed a small 1 amp linear
12 VDC supply to run the fans. I found a space off to the side in the
cabinet. Care had to be taken to not interfere with the CRT, or anything
else. 

-- 
Jerry G.
======
"Dave M." <gadget007@rochester.rr.com> wrote in message
news:oZUad.7398$l07.1679@twister.nyroc.rr.com...
After about two years, my Sony TV's Converter chip (STRS6301) failed. I
replaced it with the original Sony chip. It was evident it's heat sink
was
getting too hot. A year or two later that converter chip failed. I
replaced
it with the ECG 7046 cross. That chip lasted 6 years, then blew.
Inspection
of all these chips showed blistering and discoloration of the poly case.
Unless too much current has been drawn over all this time, I did notice
the
heat sinks fins are placed horizontally, which prevents air convection
between the plates. I'm considering installing a mini-fan against the
heat
sink fins.
Is there another solution (perhaps in a bulletin) for this overheating
problem?
Thanks,
Dave M.

Relevant Pages

  • Re: why do Panamaxes die?
    ... caps have approximately the same area in their circles. ... They don't necessarily go leaky, but if their ESR rises, they won't ... Good electrolytics read under .1 ohm ESR. ... The AnaTek Blue is an inexpensive commercial ESR meter, ...
    (rec.audio.tech)
  • Re: Model #24PT6341/37 Phillips shut down
    ... Did you use an ESR meter to check the caps??? ... I have had defectieve high voltage multipliers in TV sets also cause ... case of this module going defective, the power supply can be put in to ...
    (sci.electronics.repair)
  • Re: Mitsubishi cs-2710ra vertical problem
    ... you have to have an ESR meter to fix these sets is just WRONG. ... but you can get virtually all of the bad caps in these mitsubishis ... likely have corrosion from electrolyte leakage. ...
    (sci.electronics.repair)
  • Re: why do Panamaxes die?
    ... caps have approximately the same area in their circles. ... They don't necessarily go leaky, but if their ESR rises, they won't ... I just finished building a meter based ... Good electrolytics read under .1 ohm ESR. ...
    (rec.audio.tech)
  • Re: 2 leg crystal on FPGA: Lattice vs Xilinx
    ... I can't address the specific chip, and you have to think about ... on a recent design using a Xilinx 5V CPLD, ... My caps were 15 pF (xtal vendor recommended 18 pF, ... outside the input range so the internal signal did stop. ...
    (comp.arch.fpga)