Hi Gents
This is outside my normal area of experience (speaker building, DAC, digi amp builds). I hope that you can help.
I have a broken YAMAHA YSP800 sound bar. It does not turn on. I have another unit that works, and I have swapped over the power supply boards, and the broken one works, so I can safely say that the problem lies here.
Where do I start to find the broken component?
I have voltmeters, and a LCR meter.
Suggestions please.
Thanks.
This is outside my normal area of experience (speaker building, DAC, digi amp builds). I hope that you can help.
I have a broken YAMAHA YSP800 sound bar. It does not turn on. I have another unit that works, and I have swapped over the power supply boards, and the broken one works, so I can safely say that the problem lies here.
Where do I start to find the broken component?
I have voltmeters, and a LCR meter.
Suggestions please.
Thanks.
Ok. I have done some googling and it appears that this is a common problem with yamaha sound bars.
The 22nf 630v red capacitor to the right of the fuse is prone to failing. This cap on my broken board measures about half that of the one off the working board.
Can I use any kind of cap to replace it (22nf) 630v or higher. What is the difference between boxed caps, and the blobby looking ones?
Which of these would be suitable?
WIMA,MKP1J022203F00JSSD,CAPACITOR, 5%, 22NF, 630V | eBay
PANASONIC,ECQE6223JF,CAPACITOR, FILM, 630V, 22NF | eBay
PANASONIC,ECWH8223HA,CAPACITOR, 800V, 22NF, 3% | eBay
Thanks again
PANASONIC,ECWH8223HA,CAPACITOR, 800V, 22NF, 3% | eBay
that's the one i would use to replace the broken cap.
that's the one i would use to replace the broken cap.
Did you check the fuse? (the one in the photo is clearly blown).
..
This brings me to the question: What component on the board went ballistic to cause the fuse to blow? Naturally, a really bad Capacitor could do this - but then you would notice the bulged cap.
..
Normally the output transistors fail and draw too much current (causing the fuse to blow).
(you check power transistors by using a diode test across the Collector and emitter leads - if it is blown it will be either open, or shorted. Shorted output transistors will generally be the cause of blown fuses, open transistors just don't work). Naturally, there are "other" parameters, but this parameter test is the simplest to locate shorted output transistors.
..
Check the Power Supply Rectifier Diodes (using the VOM measure the diodes with the leads across the diode, then reverse the leads. You should see a low resistance in one direction, and significantly higher resistance in the opposite - reversed - direction).
...
Dave
Phoenix, AZ
..
This brings me to the question: What component on the board went ballistic to cause the fuse to blow? Naturally, a really bad Capacitor could do this - but then you would notice the bulged cap.
..
Normally the output transistors fail and draw too much current (causing the fuse to blow).
(you check power transistors by using a diode test across the Collector and emitter leads - if it is blown it will be either open, or shorted. Shorted output transistors will generally be the cause of blown fuses, open transistors just don't work). Naturally, there are "other" parameters, but this parameter test is the simplest to locate shorted output transistors.
..
Check the Power Supply Rectifier Diodes (using the VOM measure the diodes with the leads across the diode, then reverse the leads. You should see a low resistance in one direction, and significantly higher resistance in the opposite - reversed - direction).
...
Dave
Phoenix, AZ
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