Anybody here good with solder? Onkyo help (1 Viewer)

[schan1269]

The NR807 I inherited for my dead 707 stopped producing audio yesterday.I called the shop and they said to bring it in. Took the guy a whole 5 minutes to "re-ball the solder"(???) On the Texas Instruments secondary A/D chip. The chip has the direct correlation to speaker set up.Anybody know a permanent fix?This shop says the current "making do" lasts 6-8 weeks...till it needs reheated(according to them, coincides with our gov requiring leadless solder when these were made).

 

[Jason Charlton]

Can't speak to any permanent fix, but I can clarify what they did...

I've only heard the term "reflow", but I can presume that's what the tech meant when he said "re-ball". Over time, solder joints can crack creating voids between the components. You can re-heat the solder and form a "fresh" joint that solves this problem (sometimes adding a bit more solder if the original joint was insufficient). We do it in the pinball community all the time (some machines are VERY old and have been through hell and back).

I've not heard of this sort of repair not lasting long, but we use 60/40 solder on pinball machines, not the lead-free, so perhaps his claim does have merit.

Cracked solder joints are often caused either by vibration, or maybe temperature extremes. Not sure there's much you can do for the first, and I can't imagine overheating being an issue for someone with your experience with HT gear.

I'll be curious to see how long this lasts.

 

[schan1269]

This guy says the vast majority of Onkyo and Denon failures(Not related to power supply) are the solder joints of the DSP chips. Their intermediate failings are what causes the caps to go. Caps are just a side effect.There is a video on youtube( easy to find..."nr807 no sound") showing a guy who put 3 gu10 mr11 halogens on the board.The only one necessary(if you watch the video) is the far right one. What that one in the video does is what most of them do, if you catch the chip issue before it fries any caps(if you watch this video, 2 minutes is all it takes. The "speaker diagram", Onkyo owners will spot it immediately, is missing. When the pops back up, it works).This heat issue is a 400-600 degree problem. This era of Onkyo is a camp stove. It sits on a table and the top gets to 150 degrees. The heat sink gets to 195 before the fan kicks on.