[sdiy] Silver series TL074/84 op amps

[mskala at ansuz.sooke.bc.ca]

On Sat, 19 Mar 2016, Nils Pipenbrinck wrote:
> I have come across some silver plated IC packages before. I have a few CA3140
> here that are coated. Phillips did silver printing on transistors for a while.
> I have a bunch of BC558 transistors here that are silver coated with black
> printing. They are the real thing.

I have some 2N3904s like this.  Purchased from Digi-Key some years back.
My guess is that at least with the transistors there may be more than one
type with similar enough specs that it makes (or made) sense to
manufacture a generic batch that could qualify as more than one type and
then (possibly after testing and sorting them) rebrand some of the batch
as a type other than what was first stamped on the package.  I bet
educating customers that "This type printed with a different number is
perfectly interchangeable with the 2N3904 you wanted" has a cost at least
in the same ballpark as slapping some paint on the device.

At the very least, the black on silver printing is a lot easier to read
than the markings on many other transistors.

-- 
Matthew Skala
mskala at ansuz.sooke.bc.ca                 People before principles.
http://ansuz.sooke.bc.ca/