"flipper" wrote in message
...
: On Fri, 7 Oct 2005 17:29:31 +1000, "Phil Allison"
: wrote:
:
:
: "flipper"
:
: The tolerance number assumes nothing;
: they'll simply be within 1% ...
:
: ** WRONG.
:
: You need to learn a new word.
:
:
: ** You need to go get ****ed - psycho.
:
:
: New Metal Film resistors are and need to be well within the 1% error
: maximum
: to allow for aging.
:
: Sorry, but no.
:
:
: ** Prove it.
:
: With real data.
:
:
: I did, below.
:
: ** That is NOT my experience over 40 years of dealing with the critters.
:
: I don't know what you think your experience has been but the
: specification for tolerance is initial at 25C and the rest are
: add-ons. Always have been.
:
:
: ** Crap.
:
: For example
:
: http://www.universalimport.se/Mfr.pdf
:
:
: ** Meaningless.
:
:
:
: .......... Phil

Who'd have thought a 1 W resistor could lead to such heated argument :-)
Where to get is off the screen.

Just measured some 156 56K 1% BC (Philips) metalfilm resistor values.
Result: Avg 55,86 K Max: 56,26 K Min 55,69 K
average is 0,25 % off, 95% are within 0.6 %, all are within -0.6..+0.45 %

Since they are on a (much longer) roll, it's interesting to see the values
in sequence. It suggests a production process with upper and lower
trigger levels changing some production parameter , ie. values are
continuously measured and fed back into the manufacturing process,
hence some 'extreme' value on the roll will give a 'swing of values' into the
other direction and vice versa, some kind of noisy oscillation around the
mean value. From this, it doesn't seem likely such a low cost product as
a resistor is scrutinized for possible 0.1 % values, a separate more controllable
production process for those makes more sense.

It's just one batch, but measurements seem to bear out Phil's statements,
in this case

Rudy