[Boatanchors] [BoatAnchors] "NOS" Caps: Don't Trust'em; Check'um!

[rbethman]

Amen to current production Polyester film caps being bad right out of 
the package.
I test even new ones that I go buy.  Manufacturing errors occur.  The 
manufacturer's test only a sample.
That is a reality check.

My $60 Ideal DMM test capacitors for value, and I also test for continuity.

THEN they get used.

Unfortunately people assume NOS means old stuff, never opened or used.

We all know what ASSUME means.

Bob - N0DGN

On 5/4/2012 1:58 PM, David Stinson wrote:
> Arden said:
>
>> ..... A "NOS" paper cap is no better than one
>> wired into a rig at the factory...
> I actually agree.
> By "NOS," I didn't mean "old originals."
> These caps are "new production but unused and surplused"
> Polyester Film caps.
> Perhaps my definition of "NOS" needs correcting.
>
> As for really "old caps" like Micamolds and paper-
> I've thrown-away all the low-voltage ones and
> have, after long testing, successfully deployed a few
> hi-volters in low-voltage situations.  Some have been
> in service without trouble for years.  I remember one failure,
> but at 45 volts B+ it did no harm.
> The RAAF AR8 receiver has all but one original WWII
> black-tar-and-paper cap still in it, running at 90V B+.
> I have left it on for 48 straight hours with no issues.
> It runs cool and stable.
> The AT5 transmitter had the same type caps and
> all but one of them was bad beyond hope.
> Go figure ;-) and "Each to his own."
>
> 73 DE Dave AB5S
>
>