Dead PWB-0656-03 Power Supply

[troxel]

I am working on a PowerSpec v30dmbt, that has a dead power supply. Googling this model # found some other post that has problems with this unit, but no solutions. Looking at the board Q1 and Q20 have been replaced by previous owner who couldn't get it to work. I checked the fuse right away, and it's open. I need to order some more before I can test further.

I was wondering if there were common problems with this power supply and anything else I need to check or include in my order.

The power supply also has a p/n 6693006610 and the schematics were under HOAU242001.

[tom66]

Re: Dead PWB-0656-03 Power Supply

Remove the FETs that have been replaced and check if they are shorted now.

[troxel]

Re: Dead PWB-0656-03 Power Supply

I removed the FETs and tested fine, however noticed one didn't have a mica insulator and drain was shorted to ground. Went through all diodes, FETs, and caps, and all appear fine. Going to order the fuse and will report what happens after that.

[tom66]

Re: Dead PWB-0656-03 Power Supply

A short from the drain to ground would quite easily blow the fuse

[budm]

Re: Dead PWB-0656-03 Power Supply

I wonder if the old FET was insulated tab type, so now we may not know what the original MOSFETs were.

[troxel]

Re: Dead PWB-0656-03 Power Supply

Just wanted to follow up with this now that the fuse came in. I added the mica insulator and fuse, (and re-soldered two bad solder joints) and the power supply is now working again. I plugged it in for about 10 minutes before bed and no problems. Will have to burn it in and see if anything else goes wrong.

[troxel]

Re: Dead PWB-0656-03 Power Supply

Here are a couple more photos of the power supply without the shield.

[BigDogDaddyD]

Re: Dead PWB-0656-03 Power Supply

Hey folks. Just registered and signed on for the first time. This site was recommended by a tech friend of mine. But he's in Afghanistan and can't fix it for me.

Don't know if I am asking something that has already been answered, but does anyone know where I can get a new (or working used ) one? I've tried several outlets via Google, but no one I've found yet has one in inventory. They are listed for between $37 & $51. Thanks for your time

[vinceroger69]

Re: Dead PWB-0656-03 Power Supply

Hi has anyone got a scheme for this psu i need to know the value of c49 c24 c51 as i have a power supply with these three caps removed ready for replacement bit the owner has lost the piece of paper hes wrote the values on cheers

[selldoor]

Re: Dead PWB-0656-03 Power Supply

Hi Vince, what is it out of? One theory is its one of these


but I am not so sure- In any case it doesnt seem to have a parts list and no values that I can see

[vinceroger69]

Re: Dead PWB-0656-03 Power Supply

Thanks selldoor ive no idea at the minute its a mate of a mates so just waiting for the rest of the tv to be delivered to mine i will update you then cheers again.

[selldoor]

Re: Dead PWB-0656-03 Power Supply

In this SJpic http://assets.shopjimmy.com/media/ca...6693006610.jpg

If C39 is the one above C24 then it looks to be 1000uf? anyone agree?

[vinceroger69]

Re: Dead PWB-0656-03 Power Supply

Thanks selldoor i forgot about shopjimmy images once i get the make and model it should be easier to find a scheme for it.

[vinceroger69]

Re: Dead PWB-0656-03 Power Supply

The tvs just turned up its a old one a goodmans gtv30wlcd lcd so i anyone can help with a psu scheme that will be great in helping me too replace missing caps.

[selldoor]

Re: Dead PWB-0656-03 Power Supply

Vince- Have I been looking for wrong thing? According to one place the board
for that goodmans should be a PWB-0656-02 - not 03- is it different??

[vinceroger69]

Re: Dead PWB-0656-03 Power Supply

The boards in front of me now as im typing it says PWB-0656-03 Thanks for trying to help ive searched various psu schemes show up but no cap values etc on them.