The thread on whiskers could use a little clarification. The question about lead (Pb) in Europe is an issue over health concerns, not electrical sort circuits. Whiskers are an issue in reliability of
components and cadmium and 100% pure problem. Unless we send our solder joints deep into space or otherwise place them in a vacuum for many years whiskers are not an issue. They only form in a high
Not so Tom. Although much progress has been made with "no-clean" solders, dendrite growth is still an issue when pc board assemblies are exposed to humidity. To remove flux residues after waveline or
Tin whiskers are a different phenomenon from dendrite growth (electromigration). But you're right -- whiskers are very much a concern for everyone making the transition to lead-free finishes and sold
Motorola had and issue with whiskers inside of their filter cavities(receiver pre-selector and exciter filters) used in UHF base stations (MSF-5000). This was also an issue in some mobiles (Mostar).
"no-clean" solders, are exposed to reflow soldering processes, board washers emissions and the deionized "no-clean" solders took the trouble in the industry if Interesting Jim!! I've never seen that
Hi all, Another place this shows up occasionally is in high voltage door knob capacitors. This was pointed out by Bob Sutherland, W6PO, many years ago, and he called it silver migration. Wonder if th
This is not true. They form in any atmosphere. There are reported cases of them forming in things like GPS modules where there was a pure tin plated RF shielding lid over part of the circuitry. "Insp
the power tube flashover blows away the afterwards. Two primary mechanisms cause flashovers in tubes that are not damaged. They sometimes develop metallic whiskers and they sometimes have trace gas.
I'm no chemist, that's for sure. I was working as a manufacturing manager in a high volume electronics assembly plant at the time. But I will say all our efforts were directed at removing flux residu
Thanks Jim, radios and cell spacing on board traces. Then that's almost certainly why I've never seen a whisker problem (outside of vacuum caps and vacuum tubes) in all my years of messing around wit
Considering all the fine pitch SMTs used in modern ham gear, I'd say it's actually more of a concern than you might think. Very few ham radios use conformal coating, and lots use very dense PWBs. Ev