This is the Broadcast History section of
the Broadcast Archive

Maintained by:
Barry Mishkind - The Eclectic Engineer

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There were two great "Moving Days" for AM Radio: 11/11/28 and 3/29/41

For listeners, it probably was not too big a deal, just moving the dial a bit. But pity the poor announcer who has said for years, "Be sure to tune in tomorrow, here at XXX Kilocycles," only to have his lips (and memory) cause one flub after another, until he "burned in" the new number!

Moving Day 1928

On November 11, 1928, the Federal Radio Commission tried to restore government control over broadcasting, which had be eroded in the 1920s, after a couple of court cases, which failed to decisively end "frequency jumpers." The goals of the FRC were:

  • To reduce interference, and "clutter" on the air.
  • To provide better access to the airwaves to smaller cities, and "underserved" areas.
  • A mechanism to get rid of the "temporary" and "portable" stations.

General Order #40, issued on August 30, 1928 outlined the proposed shifting, to be accomplished at 3 A.M. on November 11, 1928. In general, it worked, and the airwaves were much "cleaner."

The frequency setup that took effect on November 11, 1928, from 550 to 1500 kHz. 
Numbers in parentheses are the zones assigned dominant use of individual Clear Channel frequencies:

550 - 630: REGIONAL
640 (5)
650 (3)
660 (1)
670 (4)
680 (5): CLEAR
690: CANADA (exclusive)
700 (2)
710 (1)
720 (4): CLEAR
730: CANADA (exclusive)
740 (3)
750 (2)
760 (1)
770 (4): CLEAR
790 (5)
800 (3)
810 (4)
820 (2)
830 (5): CLEAR
840: CANADA (exclusive)
850 (3)
860 (1)
870 (4): CLEAR
880 - 900: REGIONAL
910: CANADA (exclusive)
920 - 950: REGIONAL
960: CANADA (exclusive)
970 (5)
980 (2)
990 (1)
1000 (4): CLEAR
1020 (2): CLEAR
1030: CANADA (exclusive)
1040 (3)
1050 (5)
1060 (1)
1070 (2)
1080 (3)
1090 (4)
1100 (1)
1110 (2): CLEAR
1130 (5)
1140 (3)
1150 (1)
1160 (4)
1170 (2)
1180 (5)
1190 (3): CLEAR
1200 - 1210: LOCAL
1220 - 1300: REGIONAL
1310: LOCAL
1320 - 1360: REGIONAL
1370: LOCAL
1380 - 1410: REGIONAL
1420: LOCAL
1430 - 1450: REGIONAL
1460 - 1490: REGIONAL (high power)
1500: LOCAL

Moving Day, 1941

It was on March 29, 1941 that the Federal Communications Commission mandated that most stations move to a new location on the dial. This was at the same time that the 1500-1600 portion of the band was opened up for use by commercial stations.

As in 1928, the FCC hoped, by "spreading out" the assignments, to reduce "congestion" on some channels, in turn reducing the interference exchanged by stations, and conform to the international agreement, NARBA, that was negotiated with Mexico and Canada.

The following appeared in the St. Petersburg Times on March 29, 1941:


St. Petersburg Times, March 29, 1941

Dear Mrs. Jones: Let's be a good sport about one of life's dizzier difficulties you're going to experience today. As on dozens of other Saturdays, you will buzz into the living room, push your radio dial button and whisk back to the kitchen to fluff Saturday night's pie meringue to the dulcet tones of your favorite crooner. 

But for the sake of all those meringues and custards, Mrs. Jones, let's face it. This morning was spring moving time on the airways. Your push button dial system, if hubby forgot to change it last night, is as useless as yesterday's salad. Because this morning, Mrs. Jones, at exactly 3 a.m., 802 of the nation's 893 standard broadcast stations changed wave lengths. 

Local stations WTSP, WDAE and WFLA all are affected.

This isn't any spring cleaning orgy cooked up in an idle moment by the Federal Communications commission. It will mildly inconvenience thousands of radio set owners. Commission hopefuls beg them to be Polyannas. 

"Nobody likes moving day," quoth Chairman James Lawrence Fly in an address broadcast last night via NBC. "But the nuisance soon will be over while the benefit - better reception and less interference -will continue to accumulate during the years." 

Today's dial jam session is the direct result of a conference at Havana, Cuba, called in 1937 to co-ordinate the assignment of air space to radio stations in North America and minimize interference. 

Canada, Mexico, Cuba, the Dominican Republic and Haiti joined the United States in ratifying the resulting agreement. 

"Bootleg" stations, such as some which had operated across the border in Mexico, were outlawed by the agreement. 

Here are the changes made by United States stations:

Ninety-one stations between 550-720 kilocycles remained unchanged.
Twenty-one stations between 740-780 kilocycles advanced 10 points. 
Twenty-two stations between 790-870 kilocycles advanced 20 points.

Six hundred thirty-three stations between 880-1450 kilocycles advanced 30 points, and 11 
stations in that group advance 40 points. 

Eleven "clear channel" stations between 1460-1490 kilocycles advance 40 points. 

Sixty-three stations on 1500 kilocycles moved back 10 points.

Forty-one stations changed at variance with the general pattern.

Local Station Changes

           Previous New
WTSP 1370 1380
WSUN 620 620
WDAE 1220 1250
WFLA 940 970

For a complete list of frequency changes, see the OLDRADIO infobase.

The Broadcast FAQ

Copyright 2000  by Barry Mishkind. This material may not be reproduced or reposted in whole or part without express approval.

Many thanks to Thomas White, Donna Halper, Xen Scott, and many more, who have contributed to the information flow.

Additional information is welcome (see email below) or mailed to Barry Mishkind at 2033 S. Augusta Place, Tucson, AZ 85710

Thanks ... hope you found it interesting!