TV/VCR/Stereo Troubleshooting/pioneer sd-p404


i have an old rear proj.that was given to me  the only thing i could find was a blown up diode by the hv-transitor i couldnt read all the numbers so i replaced it the closest i could ive resoldered almost all the boards and i still get audio but no picture i dont have a schematic i checked the resistors around the diode seem to  be in tolerance any ideas or should i junk it did they have decent pictures ive never seen one another words is it worth messing with?

Failure of the convergence circuit is very common for all RPTV regardless of brand name.

Probably, you will need to replace the STK chip - which is often the cause.  There are convergence repair kits for nearly all RPTV extant.  They usually cost around $75 and require 3 or 4 hours labor to do the job.

And, of course it could be loss of high voltage - which is very common as well.  The cause could well be the horizontal deflection transistor is bad and needs replacing.  

Thirdly, if the HOT is good and still no picture or raster you may need to replace the flyback transformer.  They cost around $40 and a few hours to replace it.

RPTV are now obsolete and manufacturers have stopped production.  They are quickly being replaced by flat screen tvs (LED, LCD, Plasma, etc.)

My opinion is that old big screen crt based sets are never worth the investment to keep them going.  Now days you can find them in perfect working order listed in Craigslit setting on the curb for pickup by the first there.  I don't think RPTV sets have any value in the consumer electronics market.

If you wanted to repair your set just for the fun or educational experience would be okey.  

Hope this helps.  

TV/VCR/Stereo Troubleshooting

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