Master Control

(Second View)

Right: In addition to more equipment racks, this photo show the master control console where the real business of this room was done. MCR second view

Master control in general funneled input from the six original studios and any number of temporary remote ("NEMO") points into eight outgoing channels. Two of the outgoing channels were reserved for NBC's Red and Blue networks. Two more channels fed the transmitters of NBC's owned-and-operated stations in Chicago, WMAQ (which typically carried Red network programing) and WENR (which generally carried the offerings of the Blue network). The remaining channels were assigned to special, temporary networks ("jobs", in the NBC parlance) set up for specific occasions, and to NBC's secondary outlets in Chicago (KYW, owned by Westinghouse; WCFL, owned by the Chicago Federation of Labor; and WLS, owned by Prairie Farmer Magazine) which carried some NBC programing when the facilities of WMAQ and WENR were otherwise occupied.

Given the fact that NBC had two networks to service, it was often the case that two or more of the Merchandise Mart studios were simultaneously feeding programs. Master control could thus become a busy room indeed. To learn how one control operator could simultaneously switch two networks and two local stations, click here.

Before you leave this location, take note of the large empty rectangular on the wall above on the left. Not long after this photograph was taken, a cartographer from the Rand McNally Company was brought to master control to execute a commission. For a number of days, and with the aid of a ladder and scaffolding, he first covered this space with canvas and then painted a large map of the United States upon it. He indicated all the cities where NBC owned stations or had affiliates. In one corner he painted the old NBC logo (identical to the one you've seen elsewhere on these pages) and a representation of an RCA model 4A microphone. Then, wherever there was a station that carried NBC broadcasts, a hole was drilled and a small colored electric light was installed: a red light for a station that carried the Red network, a blue light for a station that carried the Blue network, and an orange light for a station that belonged to NBC's Pacific Coast network. What resulted was a grandiose visual representation of the NBC networks.

Right: The NBC network mural as it appeared in September, 1989.
NBC network mural

Over the years this mural was modified to reflect changes in NBC's structure. After the Blue network was sold to the entity that became ABC, the blue lights were removed. The holes were filled and painted over. The Pacific Coast lights were changed from orange to red. The representation of the model 4A microphone was replaced with with a representation of a "modern" model 44A.

Notwithstanding this room's transformation into "Video Central"(and notwithstanding NBC's eventual departure from the radio business), the map remained in place until NBC left the Merchandise Mart. Its lights generally remained burning. Engineers, some of them perhaps religiously, replaced those that had burned out. In a way, the map was like a crucifix above an altar.

My son was especially fascinated by the map. He began coming to work with me on occasion from his second year onward. By the time we learned we were moving to a new facility he was in his teens. "What's going to happen to the map?" he asked me. I didn't know. Nor did anybody else.

A group of preservationists formed among the NBC staffers. Eventually the company announced it would try to save the map. At some point after we moved to the new NBC tower, but before our lease at the Mart expired, the canvas was removed from its mounting, rolled up and put in storage.

In the fall of 1995, NBC announced that it would give the map to Chicago's Museum of Broadcast Communications. Hopefully the Museum will find a place to properly display it.

Return to the 1930 Studio Tour Guide

Introduction and main index to this site
WMAQ radio history | "Amos 'n' Andy" | "Fibber McGee and Mollie" | "The Breakfast Club"
Dick Kay | Television at the Merchandise Mart | 1970 television facilities tour | Channel 5 turns 20
The "Chicago School" of television | "Kukla, Fran and Ollie" | Dave Garroway | Mary Hartline
"Lights Out" | Sound effects | 1930 studio tour | WLS | "Empire Builders" | Barry Bernson
Floyd Kalber | The Queen of Love and Beauty | "Today's Children" | Staff announcers | Carol Marin
Ron Magers | Studs Terkel l "Chicago Tonight" | Channel 5 News scrapbooks |Roger Miller recalls
Zoo Parade | Clifton and Frayne Utley | Val Press | Len O'Connor | Johnny Erp | Bill Ray | Daddy-O
Experimental Television: 1930-1933 | Bob Deservi | Kermit Slobb | Ding Dong School | Quiz Kids
Bob Lemon | The Korshak Chronicles | KYW: The Chicago Years | WENR | O.B. Hanson | Renzo
Jack Eigen | Ed Grennan | The World's Best Cup of Coffee | Glenn Webster | Mr. Piano | Hawkins Falls
Chicago Television for Kids |
Radio Hall of Fame |The NBC News Night Report: 23 February, 1967
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