Author Topic: Panasonic 616 PBX Odd Malfunction  (Read 3282 times)

Offline oldguy

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Re: Panasonic 616 PBX Odd Malfunction
« Reply #30 on: November 04, 2017, 01:38:28 PM »
Thanks James, I have a couple 616s that need work. Your experience gives me hope I can fix mine.
Gary

Offline James

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Re: Panasonic 616 PBX Odd Malfunction
« Reply #31 on: November 06, 2017, 03:01:38 PM »
I'm glad I could help. The only other thing I would recommend is don't use lead free solder. I tried lead free solder years ago and could never get a decent solder joint with it, so I went back to 60/40 rosin core solder.

Offline TelePlay

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Re: Panasonic 616 PBX Odd Malfunction
« Reply #32 on: November 06, 2017, 03:16:00 PM »
The only other thing I would recommend is don't use lead free solder. I tried lead free solder years ago and could never get a decent solder joint with it, so I went back to 60/40 rosin core solder.

Never used it in that it requires a higher temperature (188 vs 220 degrees F) melting point, and I think (IIRC) it also needs a special flux.

Melting point is a function of the metals used and their concentrations in the mix. They use a really low melting point solder (Wood's metal) to capture crystals in it for crystal radios, almost hot water temperatures with it 158 melting point.

Nothing better than 60/40 rosin core for electrical and tin lantern work except today's price for a 1 pound spool.
            John . . .

              

Offline James

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Re: Panasonic 616 PBX Odd Malfunction
« Reply #33 on: November 06, 2017, 04:09:50 PM »
That explains why it never worked for me. I remember reading somewhere that it can also develop tin whiskers over time.

Offline twocvbloke

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Re: Panasonic 616 PBX Odd Malfunction
« Reply #34 on: November 07, 2017, 02:12:33 AM »
I've used tin solder in the past and I hated it, never worked right, never flowed properly (bearing in mind I wasn't going to buy a new iron just for a new type of solder that nobody in their right mind would use!!), went right back to proper 60/40 leaded solder, it just works... :)

Thermal stress cracking is an issue for tin solder too, it's a problem a lot of modern electronics suffer, particularly ball-grid array chips, such as integrated CPUs, graphics chips and general integrated circuits used on various modern electronic things, where you can't even get to the solder to reflow it by hand and have to use careful and directed heat to get the solder to melt, reflow and reconnect, and if that doesn't work, you have to remove, clean and re-ball the chips to get them back in, all very fiddly work and requiring some expensive equipment...

And the tin whiskers, that's been known about for years, particularly where metal pins or contacts have been tin coated, but not covered with solder, resulting in the growth of crystalline tin oxides that are conductive, and when they reach an adjacent pin, POP, there goes your component...