need help finding alternate 24v solder point.

[crbn79]

I have an Olevia 265t. I've narrowed my problems to a short on the main board for the 25v hot. I tried to clean it up and fix it but the short remains.

I think my next option is to figure out an alternate connection point for the 25v wire. This way I can pop the shorted prong out and avoid the shorted area.
I know I should probably look into a replacement main board however I cannot find them ANYWHERE, it is out of stock everywhere I check.

Pictures below.

[Mr Bill]

Re: need help finding alternate 24v solder point.

I found 1 vendor that has it in stock. Check the numbers to make sure. An expensive board.

http://www.nohoelectronics.com/produ...ain-board.aspx

Hope this helps

[crbn79]

Re: need help finding alternate 24v solder point.

Thanks, that is indeed the board I need. A bit more expensive than I was hoping. I've seen them from $50-150 out of stock. At that price I definitely want to try out the 25v relocation if nothing more than to make sure there are not any further problems before I sink close to $200 into it.

Just learned of a potential complication. The 265t and 747i shared the same part number but the board for the 265t has a hookup to signal the second power supply which the 747 board does not.

[selldoor]

Re: need help finding alternate 24v solder point.

Pic 1 is too blurry - others are slightly better can you mark them up where you located the short. Caps c2099 c2127 look a bit askew are they ok?

[crbn79]

Re: need help finding alternate 24v solder point.

Here are a couple of high quality marked pictures. I have replaced one cap on the main board which tested okay but looked funky. This main board was a warranty replacement part about 1 year ago. The original had the sound board go out.

As for all the other caps, I have checked them and reflowed the solder on most just to be sure there isn't any cold joints.

[selldoor]

Re: need help finding alternate 24v solder point.

Ok - did you keep the old board? you could trace from that where the 24 pin goes. How is it shorted - is it a double sided board and the solder on the bottom of the pin is not meant to attach it to the board outside the ring and the through will be attached to the trace on the top of the board?
Did you look at c2099 in the same picture is it meant to be like that? again if you have your old board you could check

[crbn79]

Re: need help finding alternate 24v solder point.

Ok - did you keep the old board? you could trace from that where the 24 pin goes. How is it shorted - is it a double sided board and the solder on the bottom of the pin is not meant to attach it to the board outside the ring and the through will be attached to the trace on the top of the board?
Did you look at c2099 in the same picture is it meant to be like that? again if you have your old board you could check

I wish they had left the old board, I could just run audio through my surround sound if that were the case!

As for C2099 I thought the same thing at first, that is actually 2 caps with the input sides stacked on top of each other. The back side of the board has about 40 setup the same way.

I'm not quite sure where the 25v+ is supposed to be connected. When it first showed signs of shorting the area around the back side was completely melted away from the pin, I figured it was simply a cold joint so I reflowed it. Reflow was not the correct answer unfortunately.

As of right now I'm afraid it may indeed be a multilayer board with the 24v connecting somewhere in the middle layers. This is why I'm hoping someone can steer me to an alternate solder point.

[tom66]

Re: need help finding alternate 24v solder point.

Try this - http://www.youtube.com/watch?v=XhqwC3BFBug&feature=plcp

[selldoor]

Re: need help finding alternate 24v solder point.

So at the moment does it connect to left hand pin of U100 on top of the board and possibly the two outer pins on U109 and the through just below C2140

[crbn79]

Re: need help finding alternate 24v solder point.

Thanks for that link tom, I've heard of ppl using the freeze spray but that video explains it perfect!

selldoor: I think your correct, I just sucked all the solder off the back side of the 25v, when I originally looked at it the solder was indeed touching the backside pad, now that it's clean you can clearly tell it wasn't intended to do so.

Sorry if I'm doing some basic mistakes, I'm working with kids running around and between work and HVAC emergency calls. Tends to take my mind off task and I miss things.

[selldoor]

Re: need help finding alternate 24v solder point.

Not a problem - just go at your own pace - perhaps say if your going off for a couple of hours/days then we know not to keep looking at a thread.
Do you need to check out the other pins - were they all unsoldered/ resoldered at some point.
I suppose the big question is if the 24v did any damage when connected to something it shouldnt have been.

[selldoor]

Re: need help finding alternate 24v solder point.

I am also not sure if the end pin is the 24 v there are only 5 labels and 6 pins.Are the pins labelled at the other end of the cable.

If U100 is an FS8860 it is only low voltage - what is the rest of the part number - depending on that it seems the pins on the U100 can be gnd or voltage see attachment
What is part no of U109.

[crbn79]

Re: need help finding alternate 24v solder point.

Here is where i am at now. I pulled the pin on the far left of the connector and cleaned the 3 layers of trace as best I can. I'm getting continuity between U100 and the 2 hots as well as the grounds which means no good. I'm going to pull the 2nd hot pin and see what's going on with it. I know the back side is supposed to be the Ground with the front side and middle layer being hots for the 25V. Now figuring which pin goes to which layer should be fun.

[crbn79]

Re: need help finding alternate 24v solder point.

I am also not sure if the end pin is the 24 v there are only 5 labels and 6 pins.Are the pins labelled at the other end of the cable.

If U100 is an FS8860 it is only low voltage - what is the rest of the part number - depending on that it seems the pins on the U100 can be gnd or voltage see attachment
What is part no of U109.

according to that pdf u100 should be 1-gnd 2-out 3-in 3.3v output

Not seeing a U109, if you mean u101 it's fs8860 18PJ711B

Here is a picture of the pins with the connector removed.

[selldoor]

Re: need help finding alternate 24v solder point.

U109 is on the back of the board - I see there are 2 x25v pins
can you test the holes for continuity to U100 and U109 I am going awol for
an hour as have been elected to make dinner!

[crbn79]

Re: need help finding alternate 24v solder point.

u109 is on the back of the board - i see there are 2 x25v pins
can you test the holes for continuity to u100 and u109 i am going awol for
an hour as have been elected to make dinner!

720413

[crbn79]

Re: need help finding alternate 24v solder point.

I've started cleaning up the burnt area and seperating the layers and my continuity has dropped from 000 to 84k between 24v and ground. I'm working slow getting all the layers pulled apart around the damage and hoping I can get the continuity broken.

[crbn79]

Re: need help finding alternate 24v solder point.

Well, after some cleanup I can now count at least 5 layers to this board. There's little to no chance I'm going to be able to figure 5 layers out so looks like I'm back to searching for a less expensive replacement board.

Right now the only vendor which has it is Noho @ 179.99 +tax and shipping.
http://www.nohoelectronics.com/produ...ain-board.aspx

The part number I need is SC0-P508201GSI0 with the white connector to activate the 2nd Power supply.

[selldoor]

Re: need help finding alternate 24v solder point.

I thought they only had multilayer boards in laptops If you can sort out the damage so that it is no longer shorting someone (most people) more knowlegable regarding circuits than I may be able to answer the initial question of where else you can introduce 24v. Perhaps by that 35v capacitor??
I cant find anything on U109 but as ive managed to rub fresh chilli into my eye
I am not seeing much at all!!

[tom66]

Re: need help finding alternate 24v solder point.

The board is likely 6 or 8 layers.