Hello,
I have a JCV set that broke not long after purchasing new. I was lucky enough to find a well documented issue with the set that caused the problem. The problem I am having is I can find no one who carries the parts.
Could you please tell me if you can sell me these parts or where I can get them?
***See article at bottom of email.
Make: JVC
Model: AV-27730
Parts:
R421
D421
IC421 - LA7832
C424
D422 - Is this a tiny zener diode that is across vertical output to ground? I could not get a number but was told it was next to the heat sink for IC421. This is the number off the diode closest to IC421
Thanks very much
Billy M
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ARTICLE
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This JVC model based on this chassis in different JVC models frequently comes in w/ dud vertical or bad solder joint on vertical IC. Open up and turn on TV, turn up G2 (screen) slowly, if you get horizontal line, turn it off NOW to prevent any more screen burn, return G2 to original position. Vertical is gone, gather up these necessary parts:
What you need:
1W 1.2ohm (R421) Will be open because vertical IC shorted first.
Maybe a high speed 1A diode (D421, check it for short).
Both are near flyback for the vertical 26V supply, also this is used by jungle as well.
Vertical IC part number LA7832.
Find 100uF 35V capacitor in the vertical circuit and replace it with
100uF 35V or 50V rated at 105C degrees.
Also check the tiny zener diode across vertical output to ground. If shorted, replace it with 75V 1/2W or 1W zener.
The main problem: too small heatsink (often made of steel, vast lousy material for an heatsink), runs very hot, slowly drying out that 100uF cap and bam vertical IC dies, taking out that 1.2 ohm resistor sometimes also that diode in series with it, rarely this zener diode also shorts.
I suggest that you bolt on aluminum flat bar to this original heatsink. Space there is cramped, go outwards. Drill new pair of holes for two screws or bolts & nuts. This will increase surface area for heat to radiate away.
The cost of these parts should not cost more than 20.
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