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 Post subject: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 22 Apr 2020, 13:12 
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My Onkyo DX-V500 (240v PAL/NTSC) has suddenly died on me and I'm at loss of what to do. Pre-warning: I am teaching myself how to use a multimeter and I'm not entirely sure I know what I'm doing!

I've uninstalled the PSU board and the glass fuse is fine.

I've tested all the caps/resistors and diodes on the board for continuity and they seem fine (but I've read that continuity doesn't necessarily mean it works!?). I am unable to test the blue ceramic capacitors because...I don't know how to. I've tried measuring Ohms and continuity on the blue caps and nothing is registering. Google tells me though that blue cermaic caps rarely fail though, so...

My electronics experience is severely limited but I don't want to trash the player over a potentially simple fix.

Does anyone know which caps/resistors/diodes commonly fail on these PSU board? Any pointers and tips would be greatly appreciated!!

The power board is model VWR1247.


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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 22 Apr 2020, 15:21 
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I don't know how to test caps, I did do a search once and saw something about using a battery to fill the cap to make sure it holds
the power.

But do this at your own risk.

Another thing is to just replace the caps if you do know the power is the real issue as you will end up spending about 10 bucks total on caps.

You can also if you have another PSU try swapping it to make sure that's the issue then replace parts.

Good luck.
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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 22 Apr 2020, 15:52 
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There is no unambiguous way of testing caps other than removing them from circuit and using an ESR (Equivalent Series Resistance) meter together with a table of acceptable ESR values. (But then, having removed an ancient electrolytic cap from a board, why not just replace it anyway? They all go bad eventually.)

What makes you think the problem is on the PSU board anyway? It's quite likely, but not necessarily. Is the machine totally dead? I would start by using the voltmeter to look for the output voltages from the PSU, first in isolation, then under load during operation or attempted operation. If the PSU does seem suspect, look for bad solder joints (dry joints) with a magnifying glass - best from the underside of the board. They appear as a very fine line or crack around the solder joint. Some of the PSU board does look a bit blackened in your picture.

Best of luck and be careful round the PSU even when turned off. Plenty of shock potential there.
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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 22 Apr 2020, 22:30 
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It is interesting is this unit had a VWR1247 power supply inside and the DX-V500 service manual it says it is a VWR1268. VWR1247 is covered in the CLD-V860/CLD-2750K service manual.

https://www.giangrandi.ch/electronics/s ... sfix.shtml was helpful for me, and there are a lot of videos on Youtube on the topic.

The only known issue I can recall is the arc suppression fault that Kurtis has mentioned before, but I do not see it in the schematics (it doesn't look like the 230V supplies have them). You would also have a blown fuse.
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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 23 Apr 2020, 09:44 
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Thanks for the replies everyone!

nextwednesday wrote:
There is no unambiguous way of testing caps other than removing them from circuit and using an ESR (Equivalent Series Resistance) meter together with a table of acceptable ESR values. (But then, having removed an ancient electrolytic cap from a board, why not just replace it anyway? They all go bad eventually.)

What makes you think the problem is on the PSU board anyway? It's quite likely, but not necessarily. Is the machine totally dead? I would start by using the voltmeter to look for the output voltages from the PSU, first in isolation, then under load during operation or attempted operation. If the PSU does seem suspect, look for bad solder joints (dry joints) with a magnifying glass - best from the underside of the board. They appear as a very fine line or crack around the solder joint. Some of the PSU board does look a bit blackened in your picture.

Best of luck and be careful round the PSU even when turned off. Plenty of shock potential there.


Yes the machine is totally dead!

Ok I'm gonna ask a dumb question - you said you check output voltages from the PSU in isolation - can you be more specific? What does that mean exactly?

This is the multimeter I use https://www.petervis.com/meters/dt830d/dt830d.html Is it possible to check voltages with it? I connected the power to the player and tried using the DCV part of the multimeter but was only geting a reading of 001 or 002. Again, I've no idea what I'm doing!

Yes you're right, part is a big black and smells a bit burned. But I check the resistance of all the resistors and they seemed fine. I'm struggling to check caps - some show me a reading when I measure Ohms, but others don't and I'm not sure why.

cplusplus wrote:
It is interesting is this unit had a VWR1247 power supply inside and the DX-V500 service manual it says it is a VWR1268. VWR1247 is covered in the CLD-V860/CLD-2750K service manual.

https://www.giangrandi.ch/electronics/s ... sfix.shtml was helpful for me, and there are a lot of videos on Youtube on the topic.

The only known issue I can recall is the arc suppression fault that Kurtis has mentioned before, but I do not see it in the schematics (it doesn't look like the 230V supplies have them). You would also have a blown fuse.


Thanks for your help! I downloaded the CLD-V860/CLD-2750K service manual but it only seems to like the VWR1268 parts and not the VWR1247! I could theoretically change all the suspect parts but I don't know their value and can't find any of the capacitors in the service manual.
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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 23 Apr 2020, 15:57 
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brmanuk wrote:
This is the multimeter I use https://www.petervis.com/meters/dt830d/dt830d.html Is it possible to check voltages with it? I connected the power to the player and tried using the DCV part of the multimeter but was only geting a reading of 001 or 002. Again, I've no idea what I'm doing!

Yes, just keep in mind some parts are AC and some are DC. i.e. voltage up to the two center legs of D1 (the bridge rectifier that rectifies AC into DC) is AC. The outer legs are DC. If you were to check F5, you would be looking for +12VDC so you would set your meter to DCV. Be careful not to accidentally short anything.

brmanuk wrote:
I'm struggling to check caps - some show me a reading when I measure Ohms, but others don't and I'm not sure why.

These need to be removed from the board to check with a multimeter, but as nextwednesday said, you might as well just replace them all at that point. To be clear, I am referring to the aluminum electrolytic capacitors.

brmanuk wrote:
I downloaded the CLD-V860/CLD-2750K service manual but it only seems to like the VWR1268 parts and not the VWR1247! I could theoretically change all the suspect parts but I don't know their value and can't find any of the capacitors in the service manual.

VWR1247 looks identical to VWR1268 at a glance. I just posted that because the VWR1247 scan is cleaner. Go with what is on the board first. Capacitors will have their capacitance and voltage labeled on them. i.e. 2200uF 25V. It looks like the two large caps in the top right are 180uF 250V.
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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 18 Dec 2020, 04:10 
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Well, life got in the way and I never got round to replacing the caps. I had a spare machine which was working perfectly so I was happy enough with that....until the exact same thing happened!! I was watching a movie and ejected the disc and turned off the machine. I went to turn it back on and nothing. Then I unplugged the player and heard a "squeak!" sound from inside coming from the powerboard after around 20 seconds. I've heard this sound before when switching off consoles/VCRs etc from the mains, but this sound usually happens instantly. I plugged it back in and it refused to turn on.

So now I have 2 broken machines. Why it's happened to me with two machines in the space of a few months I'll never know. The only thing I can think of (other than it being pure coincidence) is that they were both plugged into a multi-plug strip adapter thing at one point.

cplusplus wrote:
It looks like the two large caps in the top right are 180uF 250V.


I Googled the issue and found a Reddit post and sure enough it's a capacitor problem. I've managed to find all the caps locally aside from the 180uF 250v cap you mentioned. I managed to find a 250v 220uF cap so I need to research whether or not this would be a suitable replacement.

I plan on fixing these machines over the holidays so I'll report back!
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 Post subject: Re: [DX-V500 - Onkyo Pioneer clone] Won't power up
PostPosted: 18 Dec 2020, 19:47 
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By all means, let us know how it goes. The more info we have on successful fixes helps the community greatly :thumbup: .
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