Category Archives: Civil Defense History

Electric Sentry for Air Raid Warden: 1943

1943MayPM5Eighty years ago, this west coast air raid warden was subject to call at any moment, but he might need to be somewhere in his house other than next to the telephone. His solution was to use something called an “electric sentry” to alert him.

As near as I can tell, an “electric sentry” was a one-way intercom, which used the house wiring to transmit the signal. The transmitter was plugged in near the telephone ringer. He could then carry the receiver to another room in the house, or even a neighbor’s house, with the assurance that he would hear the ringing phone.1943MayPM6

Here, he appears to have the sentry receiver nearby while he repairs a radio. His daughter assists him by trying on his warden’s helmet. The transmitter is shown at right.

The item appeared in the May 1953 issue of Popular Mechanics.



Using the CB in Emergencies: 1973

Screenshot 2023-03-31 10.12.36 AMOur younger readers might find this hard to believe, but there was a time when you didn’t have a phone with you while driving. If you were in your car, you were cut off from the rest of the world. Nobody could call you, and you couldn’t call anyone else. As alien as the concept might seem, you might need to wait to talk to someone!

Believe it or not, being incommunicado in this way has its advantages. It gives you the opportunity to relax, without being bothered by someone else’s trifling concerns. Of course, on rare occasions, there are legitimate emergencies. If you car broke down, you would either have to hike to the closest payphone, or wait until a good Samaritan stops to help. Believe it or not, good Samaritans were more common then, because they realized you didn’t have a phone. Today, when people see a stranded motorist, they assume (usually, but not always, correctly) that the person has a phone. But back in the day, when you saw someone by the side of the road in trouble, you knew that unless someone stopped, they wouldn’t get any help. Armed with that information, it wasn’t uncommon to be the someone, and stop to help.

Of course, most good Samaritans are good, but there are also bad people who might take advantage of someone, especially a woman, helplessly stranded by the road. Therefore, having some mechanism to communicate, especially if you were a woman, wasn’t a bad idea. The billboard above highlights this fact, and it was seen on American highways fifty years ago, as shown here in the April 1973 issue of Popular Electronics.

Screenshot 2023-03-31 10.49.55 AMThe magazine highlighted the efforts of REACT and other CB clubs and organizations to provide someone to respond to such emergencies.  Since 1970, channel 9 had been designated as a channel for emergencies and motorist assistance.  In most areas of the country, REACT and other groups did an admirable job of monitoring channel 9, and the magazine provided a summary of those efforts, and pointers on using your CB in case of emergency.  It noted that in addition to routine monitoring of channel 9, many groups assisted with civil defense and emergency communications.  It encouraged CB’ers to monitor channel 9 whenever possible as a backup, but it did encourage waiting for organized groups to help before jumping in, since this encouraged people to join the organized groups.  One popular activity by such groups was providing coffee to motorists on holiday weekends, as shown here.

The billboard shown above was provided by the Electronic Industries Association as a public service.  The magazine provided details on how local CB clubs could contact outdoor advertisers to obtain the materials for the sign.



1943 Air Raid Tip

1943MarPM1Eighty years ago this month, the March 1943 issue of Popular Mechanics showed this preparedness tip. During an air raid, the first thing you would of course grab would be the radio. This cloth cover fits over the set and contains other items needed during a blackout. As an added bonus, it covered the front and back of the set to keep any light from leaking out.



Eclipse Litigation.

1953 CD Communications Truck

1953MarRadioNewsThe cover of the March 1953 issue of Radio News showed the new mobile communications unit for Philadelphia’s Civil Defense. According to the magazine, the unit featured complete and flexible facilities for all type of two-way communications, as well as a public adress system. It featured its own 15,000 watt power plant, along with both heating and air conditioning. In addition to police and fire frequencies, the 2, 10, and 75 meter amateur bands could be covered, permitting communications with other cities throughout the United States. And thanks to the Bell System, it included mobile telephone equipment as well as capability of up to 16 phone lines.

1953MarRadioNews2



War Emergency Radio Service, 1943

1943FebRadioRetailing2We’ve previously discussed the War Emergency Radio Service (WERS), a wartime civil defense service set up to harness the talents of amateur radio operators who were otherwise off the air for the duration of World War II.

Eighty years ago this month, the February 1943 issue of Radio Retailing takes a look at how the local radio dealer might fill part of the need in supplying equipment and expertise. The illustration shown above is a mobile repair facility, and undoubtedly some of the personnel shown here service radios as their civilian job as well.

In addition to radio operators, a role likely filled by hams, the dealers might fit into one of five other categories: Maintenance, procurement, construction, repair, and training.



1943 Emergency Generator

1943FebQSTEighty years ago this month, the February 1943 issue of QST showed this emergency generator. Hams might have been off the air for the duration, but they still had an interest in emergency needs, including WERS operations.

It was powered by a Briggs & Stratton gasoline engine normally rated at 1-3/4 HP, but the accompanying article noted that it was capable of up to 2-1/2 HP maximum as shown here. It was capable of putting out 120 volts thanks to a salvaged Dodge 12-volt generator, rewound, and was capable of putting out over 1400 watts. The field coils needed power, and that was provided by a second six-volt generator also driven by the engine.

The estimated cost of the whole unit was said to be $7.50, although the author admitted that this figure might have been somewhat “under-exaggerated.” The set shown here was the second one constructed, and a third was underway.

One of the gentlemen shown on the cover, although they’re not identified, was apparently Warren Copp, W8ZQ. The article mentioned that he was the father of then-eight-year-old actress Carolyn Lee.  We’re not sure exactly why that’s relevant, but like the author of the QST article, we believe that’s the kind of thing our readers would want to know.



1942 WERS Transceiver

1942DecRadioNewsThis woman is providing civilian defense communications as part of the War Emergency Radio Service, using a 112 MHz transmitter-receiver shown in the December 1942 issue of Radio News.

The set was completely self-contained. It’s transmitter section put out a hefty ten watts, and the batteries and dynamotor were built in to the cabinet. Both the transmitter and receiver could tune the entire 112-120 MHz band.

1942DecRadioNews2



1942 Boy Scout Civil Defense Messenger

1942OctBLEighty years ago this month, this unnamed Scout performing his civil defense duties is shown on the cover of Boys’ Life magazine, October 1942. His armband is the insignia of a civilian defense messenger, but all we know about him comes from his uniform, that he is that he’s a Patrol Leader of Troop 3 in Mt. Vernon. Unfortunately, there are dozens of towns named Mt. Vernon in the U.S., but his uniform doesn’t indicate the state.

This issue of the magazine talks about other Scouts engaged in defense related activities, but doesn’t specifically talk about the Scout on the cover. But the magazine gives an important clue, namely, the identity of the photgrapher, Emil Brodbeck, whose Amazon author page reveals that he was obviously an accomplished photographer.

According to Brodbeck’s 2003 obituary, he was born in Mt. Vernon, New York, and resided there until 1987. And according to this newspaper article, there was a Troop 3 in Mt. Vernon, NY, in 1955. So it seems very likely that this Scout was doing his part to serve the citizens of that New York community.



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1952 Omaha/Council Bluffs Floods

The spring of 1952 brought record floods to Omaha, Nebraska, and Council Bluffs, Iowa. One of the critical needs was patrolling the dikes, and local hams were pressed into action for the job. For ten days and nights, volunteers manned the dikes constantly, reporting any leaks or signs of weakness back to city hall. From there, emergency crews were dispatched to shore up any weak spots.

The equipment used here consisted of Motorola Walkie-Talkies. The equipment was supplied by the Union Pacific Railroad, and operated on the railroad’s frequency of 160.29 MHz.

This report appeared in the July 1952 issue of Radio News, July 1952,



1962 3M Aztec Kerosene Generator

1962MayRadioElecWe’ve previously reported that in the late 1950s, the Soviets led the free world not only in space, but also in kerosene powered radios. They produced a 7-tube set powered by kerosene, a thermocouple, and vibrator power supply.

But it turns out that the Americans were close on their heels, and were producing a superior product just a few years later, as shown here. This battery, dubbed the Aztec, was produced by Minnesota’s iconic 3M, and could power a transistor radio (apparently sold separately) for up to 24 hours with a pint of kerosene.

You can see a pristine example, apparently for sale, at this link, which also includes a link (currently broken) to one in a Canadian museum.

The American model produced a low voltage, which was stepped up to 6 volts with a transistorized power supply mounted in the base.  In addition to use in off-grid locales during peacetime, the set was billed as having a Civil Defense purpose for powering the important radio in the fallout shelter.