I 1920'erne, blev '''''[[Radio Manufacturers Association|RMA]] resistor color code''''' udviklet af [[Radio Manufacturers Association]] (RMA) som en farvekodemærkning af faste resistorer. I 1930 blev den første [[radiomodtager]] med ''RMA color coded'' resistorer bygget.<ref name="ARH_1932_1">Papirside 62, højre spalte: {{cite journal |title=Color coding |journal=[[Service - A Monthly Digest of Radio and Allied Maintenance]] |date=april 1932 |volume=1 |number=3 |editor-first1=John F. |editor-last1=Rider |editor-link1=John F. Rider |editor-first2=M. L. |editor-last2=Muhleman |publisher=[[John F. Rider Publications, Inc.]] |location=New York City, NY, USA |page=62 |url=https://www.americanradiohistory.com/Archive-Service-Magazine/30s/Service-1932-04.pdf |access-date=2019-11-15
|quote=Color coding of resistances used in receivers is not always according to the standard recommended by the [[Radio Manufacturers Association|RMA]]. Most of the manufacturers now are using this code. The following is a partial tabulation of receiver manufacturers and comments concerning their use of the body, tip and dot system. […]}} (NB. Part 1/2 of a list of when each radio manufacturer first started using RMA color coded resistors.)</ref><ref name="ARH_1932_2">{{cite journal |title=Color coding - Continued from April issue |journal=[[Service - A Monthly Digest of Radio and Allied Maintenance]] |date=maj 1932 |volume=1 |number=4 |editor-first1=John F. |editor-last1=Rider |editor-link1=John F. Rider |editor-first2=M. L. |editor-last2=Muhleman |publisher=[[John F. Rider Publications, Inc.]] |location=New York City, NY, USA |page=89 |url=https://www.americanradiohistory.com/Archive-Service-Magazine/30s/Service-1932-05.pdf |access-date=2019-11-15}} (NB. Part 2/2 of a list of when each radio manufacturer first started using [[Radio Manufacturers Association|RMA]] color coded resistors.)</ref> Over mange tiår, ændrede organisationen navn (RMA, RTMA, RETMA, [[Electronic Industries Alliance|EIA]])<ref name="JEDEC_EIA">{{cite web |title=JEDEC History |publisher=[[JEDEC]] |url=http://www.jedec.com/join_jedec/history.cfm |access-date=2007-09-29 |url-status=dead |archive-url=https://web.archive.org/web/20070929155400/http://www.jedec.com/join_jedec/history.cfm |archive-date=2007-09-27}}</ref> således ændredes også navnet på farvekoden. Det sidste navn er '''''[[Electronic Industries Alliance|EIA]] color code''''', men de fire navne variationer findes stadig i bøger, tidsskrifter, kataloger - og andre dokumenter siden 1930.
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