labtech_one wrote:

Everything made, no matter how hard we try will have small differences, no 2
resistors will have
exactly the same value, thats why they have a rating like 20%, 10%, 5%
tolerance they are within,
say 10% of the rated resistance ( a 100 ohm resistor may be 90 ohms or
110 ). With that in mind,
and the number of resistors in a radio, there can be 1,000's or millions of
combination. And every
component in the radio is the same way ( capacitors, transistors, wire,
coils, diodes, etc )

So no 2 radios will EVER be exactly alike, they will be ( like their
components) within 20% or 10%
of a rated 'projected' radio design. More expensive radios use closer
tolerence components so they
will have much closer performance, but cheap-o's using 20% tolerence parts,
you may be lucky if they
are even similar


The old 50%, 20% and 10% are obsolete tolerances.


Since almost everything made today uses surface mount, 5% is the worst
tolerance you'll see. 1% is common, .1% and .01% are seeing more use in
critical circuits. We were using 1% resistors and capacitors in 95% of
the locations, and 1% capacitors in critical RF, IF and Video circuits.
(Audio was treated as narrow band video).

In fact, the 1% resistors were cheaper in 2000 than the 5% they
replaced.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida