Quote:
Originally Posted by TrevorG3VLF
Early transistors had gold plated leads and soldered very easily. Unfortunately, gold and tin form a brittle intermetalic which gives long term reliability problems. Recent components do not have gold plated connections for soldering.
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I had heard of that but I have never come across a defective connection to a soldered (with tin-Pb) gold plated component lead yet , or a gold plated pcb pad. But seen plenty of trouble with tin plated leads on components growing whiskers, for that reason I'd prefer the gold any day of the week.
As far as I recall, many (not all) of the gold plated wires of components like IC's , transistors & top of the line resistors etc, were gold directly on steel, and if stored badly rust develops. I see this on a lot of vintage RAM & CPU IC's in my vintage computers.
Gold is just too expensive for most applications. That is why the fakers never use it. So its a handy thing to look out for avoiding fakes. For example if you want some genuine 2N2222's or BC107's get ones with gold plated wires.
Gold was still the mainstay for corrosion protection on the top of the line mil spec parts, or at least it was up until the 90's. And a lot of those parts are still perfect, like the miniature Teledyne relays etc. And Gold remains irreplaceable on many signal level switch contacts.
It a real shame the diode in the attached photo didn't have a gold plated lead.