The PHILCO Phorum

I have begun to test the resistors on a 46-1209 chassis. So far they have tested plus or minus about 10%. What is a general % drift that I should use for replacement?

Typically the resistor will have a "colour", whether a band or a dot etc to indicate the component tolerance, and that tolerance is probably the best guide, because that's what the radio manufacturer was happy with when they built it.

Some very early "dog bone" resistors had proprietary color schemes, but the standard soon became the B-E-D system, which stands for Body-End-Dot. The first digit is the body color, 2nd digit is the end color, and the number of zeros is the dot. If the other end is colored and is silver it is a 10% tolerance resistor, if it is gold it is 5%, if not colored then 20%.

Later resistors use the band color system where the first band is the first digit, the second band is the 2nd digit, the 3rd band is the number of zeros, and the 4th band is the tolerance.

There is a horse for remembering the color code which they taught us many years ago in electronics school in the Navy, and it goes like this... "Bad Boys Rape Our Young Girls But Violet Gives Willingly, Get Some Now."

Write the initial letters vertically in order, Black=0 Brown=1 Red=2 Orange=3 Yellow=4 Green=5 Blue=6 Violet=7 Grey=8 White=9 Gold=5% Silver=10% None=20%

I hope this little lesson makes working with resistors easier.

10% is as good as they came back then; keep them.

Thank You Gentlemen! So far so good!