HDR-Fox T2 Stability

[everthewatcher]

It’s running cooler than before; I have a Fluke infrared thermometer...

The original heatsink was black anodised, your new one is raw aluminium or white thermal paste, so of course your IR thermometer is showing a lower apparent temperature as it's emissivity is a lot lower.

...and it showed that the top left hand corner was the hottest (stood facing the front panel) at least as hot as the central part.

Does that make sense? Heat 'flows' from hot to cold. I suspect you're thinking the laser pointer does the measuring - it doesn't - or aren't taking into account the gross parallax error at close range.

But the proof is in the puddung: it doesn’t freeze any more.

It may be the mechanical stress you put the BGA package under when removing the stock heatsink has temporarily 'fixed' a broken solder ball joint.

What is the “BGA package”; where do I find it, and would the broken solder joint be visible?

As others have answered, it's the type of package the main chip is in - the one with the heastsink. And no, any suspect joint isn't visible without X-ray kit.

 

[Black Hole]

What hasn't been mentioned so far (not that I've gone back to check) is that these fine solder connections can become fractured by thermal cycling (as a consequence of differential thermal expansion). This is the reason electronics assemblies left running permanently tend to be more reliable than ones which get turned on and off (and don't forget there are joints within ICs and other components as well).

Old-school through-the-hole PCBs can be examined and re-soldered, so can surface mount with a bit more difficulty (where the contacts are exposed). BGA (and similar packaging where the joints are hidden underneath, due to the number of connections required) are a very specialist job to repair, and might as well be written off.

 

[everthewatcher]

And no, any suspect joint isn't visible without X-ray kit.

Correction: There are some clever optical inspection systems out there, e.g. www.youtube.com/watch?v=ZbXNUUtGkYA

 

[Black Hole]

That's amazing, but I think it's more useful for quality control than fault finding. Are you really going to spot a dry joint in the middle of a BGA - and even if you did, what could you do about it?

 

[everthewatcher]

That's amazing, but I think it's more useful for quality control than fault finding. Are you really going to spot a dry joint in the middle of a BGA -?

As you say it's more inspection than repair, but with a its 40mm depth of focus you should be able to spot one.

and even if you did, what could you do about it?

The usual is remove the package, re-ball it and resolder.

 

[Black Hole]

Not at home!

 

[everthewatcher]

Not at home!

You'd think, but there's lots of videos about it on YT.

 

[martinr]

You'd think, but there's lots of videos about it on YT.

Any you’d recommend?

 

[everthewatcher]

Any you’d recommend?

No experience of it so I can't recommend any, but a search on 'bga reball' should keep you happy for a bit.

 

[borisd0]

Very interested in the replacement heat sink solution, I'm wrestling with high processor temperatures. Maybe I missed it in your posts but how is the new heat sink attached?

 

[bottletop]

A relatively safe way to remove the old heatsink without applying pressure to the chip. Requires patience and strong thread, or use 2-3 strands of thread for strength but not too thick.

After removing the heatsink, the chip looks a little like an old laptop cpu.
I wonder if there are any other chips that get a little hot - maybe we should add some small adhesive heatsink like the type for the raspberry pi for to help relieve the heat.

 

[borisd0]

Brilliant! Thanks, one problem solved.

I've now have removed the MB, I thought that an underside inspection may reveal hot spots ( a browning of the surface). Apart from the general area under the processor all normal.

 

[bottletop]

On the DTR-T1000, rather than remove the original black heatsink, some people have placed an additional heatsink on top of the middle raised section to improve cooling

Youview BT T1000 - Heatsink Replacement

Hi, Has anyone ever tried to do this? For some reason, they've fitted a pitiful heatsink on this thing, no fins, just a sheet of metal with a lip at the edge (both older and new models had much more). And we've found that the rear fan was disabled by a firmware update a while back - which...

forums.overclockers.co.uk

 

[/df]

That's a lot of trouble to go to when the "broken by design" software doesn't even allow you to sort the channels in the EPG.