Editing Electronic color code (section)

==={{anchor|3-dot|6-dot}}Postage stamp capacitors and war standard coding===
[[File:EIA Capacitor Color Codes.jpg|thumb|Postage-stamp [[mica capacitor]]s marked with the EIA 3-dot and 6-dot color codes, giving capacitance value, tolerance, working voltage, and temperature characteristic. This style of capacitor was used in vacuum-tube equipment.]]
Capacitors of the rectangular "postage stamp" form made for military use during World War II used ''[[American War Standard]]'' (AWS) or ''[[Joint Army-Navy]]'' (JAN) coding in six dots stamped on the capacitor. An arrow on the top row of dots pointed to the right, indicating the reading order. From left to right the top dots were: either black, indicating JAN [[mica capacitor|mica]], or silver, indicating AWS paper; first significant digit; and second significant digit. The bottom three dots indicated temperature characteristic, tolerance, and decimal multiplier. The characteristic was black for {{val|±1000|u=ppm/°C}}, brown for ±500, red for ±200, orange for ±100, yellow for −20 to +100&nbsp;ppm/°C, and green for 0 to +70&nbsp;ppm/°C.

A similar six-dot code by EIA had the top row as first, second and third significant digits and the bottom row as voltage rating (in hundreds of volts; no color indicated 500 volts), tolerance, and multiplier. A three-dot EIA code was used for 500 volt 20% tolerance capacitors, and the dots signified first and second significant digits and the multiplier. Such capacitors were common in [[vacuum tube]] equipment and in surplus for a generation after the war but are unavailable now.<ref name="ARRL77"/>