I got a box of carbon composition resistors which are perhaps 40 or 50 years old. They are things of past, having been replaced by carbon film and metal film. They are probably made by Allen-Bradley, which were the main supplier of discrete resistors. They have the distinct dark brown base color with 4 to 5 color rings (some have a visible 5th ring for temp coeff, yellow for 25 ppm/C, most are probably 100ppm/C which is brown same as the background), and are of straight cylindrical shape with sharp ends. (The carbon film resistors have light brown base color and have end-cap bulge then tapered shape at the end). The most common ones have 1/4W power rating, with body length 0.25", diameter 0.090", lead length 1.5", diameter 0.024". The 1/2W has body length of 0.385", diameter 0.140", and 0.032" lead diameter; and 1/8W body length 0.150", diameter 0.062" and lead diameter 0.015".
One thing I noticed is that how badly they are out of tolerance. There are 5% resistors as indicated by the gold color ring. But a lot of them are more than +5% of the nominal values. All resistances are larger than the nominal value. Aging or environment conditions (such as moisture) might have a large influence, which causes at least +5% resistance value shift. But carbon composition resistors, which are not film construction, are more robust and have good surge performance, low inductance, and good high frequency capability.
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