I remember these on the radio

50C8DAN

The Cold War on the Radio Dial

Triangles at 640 and 1240 directed us to alarming news. Now it finds us. 

By Bob Greene

March 9, 2022 6:25 pm ET

An old car radio inside a classic car.

You’ll occasionally see them at flea markets and antique shops. If you don’t know what you are looking at, they will appear unremarkable: old AM radios, decades past their prime.

But examine them closely and you’ll notice something that once needed no explanation: tiny triangles at two positions on the dial. These were there for serious purposes during the Cold War, newly piquant today as the world worries what Russia may do next.

Every radio made in the U.S. between 1953 and 1963 was required to feature the miniature triangles: one at 640 on the AM dial, the other at 1240. Table radios, car radios, transistor radios: None were exempt.

This was part of Conelrad, an acronym for “Control of Electromagnetic Radiation.” In the event of a Soviet air attack, all broadcasts would go silent except for official emergency instructions over the government’s special network. The triangles, simplified versions of the Conelrad logo, were intended to help citizens, nervously hand-adjusting their radios, to find the proper spot quickly.

There was another, parallel purpose. The national Conelrad announcements were designed to emanate from a constantly shifting lineup of local transmission towers, each owned by a station whose programming had paused. In the event of an attack, each would feed the 640 and 1240 emergency frequencies. So if Soviet bombers entered American airspace, they wouldn’t be able to use the local tower signals as navigation aids. By the time they figured out where one signal was coming from, another tower would have taken over.

If this sounds rudimentary—triangles on the dial faces of radios, local towers using round-robin transmissions to confuse Soviet warplanes—it was emblematic of Cold War anxieties. Many towns had weekly tests of air-attack sirens. Residents knew the time and day the siren would sound for the test. If it blared at any other time, they would sense something amiss—and perhaps check their radios to see if Conelrad was on the air.

The Soviets never attacked, and except for dry runs and glitches Conelrad never had to be activated. Eventually advances in technology outpaced the old system. Methods of instantly disseminating information became so plentiful that Americans, with their smartphones and tablets and computers, no longer have to learn to twist a dial toward the triangles to search for alarming news. For better or for worse, the alarming news now searches for us.

Mr. Greene’s books include “Once Upon a Town: The Miracle of the North Platte Canteen.”

superwasp

Most don't grasp the complexity of the system for the time. The process to cycle the towers wasn't easy and took a lot of coordination. Pretty cool really.

railknight

Curiously, my two Sylvania built Hudson radios (rectangular push buttons), one in my '53 Super Wasp and one as a spare, lack the "conelrad" symbols on the dial despite being used in 1953 and '54 Hudsons.    

superwasp

I have the same Sylvania unit and no markings either. I know the author used the term 'required to have', but I'm not convinced there was actually legislation that required it. If there was, it may have exempted older designs. I've rebuilt several tabletop radios of that era and they didn't always have the markers either. It seems like the older units were less likely to have them. The early 60s stuff almost always seemed to have them.

jjbubaboy

Great info, thanks Dan. 
I had seen that (some years ago...) and wondered about it but never asked.
Jeff

25truck

Very interesting 
I thank you for posting that.
 I grew up in the last 60s early 70s and I remember having to practice getting under the desk at school incase of a nuclear attack.
thinking back.      I wonder how that was going to make a difference 

John