Santa Catalina Radiotelephone, 1921

1921MarRadioNews1A hundred years ago, if you were located 26 miles across the sea (40 kilometers, for those in leaky old boats) at Avalon, Santa Catalina Island, California, you could enjoy the luxury of telephone service with any telephone in the United States, thanks to the radiotelephone service operated by Pacific Telefone and Telegraph Co., as described in the March 1921 issue of Radio News.

The system consisted of stations KUVX at Avalon and KUXT at Long Beach. A complicating factor was the presence of naval station NZL, also located at Avalon. To avoid interference, the radiotelephone receiving station employed a wave trap to null out NZL’s frequency. The article gives the radiotelephone wavelength of 425 meters (706 kHz). The system was full duplex, meaning that there would be different transmitting and receiving frequencies. Since the 425 meter wavelength is discussed in conjunction with the wave trap on the receiving antenna, it appears that the Long Beach station transmitted on 425 meters, and Avalon transmitted on a different frequency.

The author described an interesting catch for an SWL as part of a test conducted by the Avalon station. He listened in on a conversation from Avalon to the mainland, which was carried by the transcontinental telephone lines to New York, where the call was carried by another radiotelephone station to a ship in the Atlantic. The author reported that the voice was a little distorted, but could be clearly heard throughout the ten minute test.

The Avalon station was powered by a motor generator, and to avoid having to restart the power, the carrier was left on 14 hours a day, with calls to and from local hotels, stores, and residents carried as needed. A licensed radio operator oversaw the transmitter, connected to an eight-wire antenna, and receiver, connected to a loop antenna. A telephone operator put through the calls, presumably with another operator at the Long Beach side of the circuit doing the same.

The system was able to transmit telegraph signals simultaneously with telephone conversations without interference. This was accomplished by “superimposing a high pitched harmonic on the carrier wave.”

A more detailed technical description of the system can be found in the December 1921 Proceedings of the IEEE.  You can also find additional references at Wikipedia, which notes that the system was replaced by a submarine cable in 1923, ending the possibility of radio listeners being able to tune in to telephone conversations.

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Icebox Experiment: 1941

1941MarPSEighty years ago, this young woman was conducting a scientific experiment to determine the best way to maintain ice in an icebox. In 1941, not everyone had a refrigerator. The icebox was still common. It was nothing more than in insulated box in which ice, usually delivered by the iceman, was placed to keep the food cold.

You had to pay for the ice, so the natural tendency of the frugal housewife would be to wrap up the ice in a towel to make it last longer. This experiment showed that this was false economy. As Popular Science, March 1941, puts it, by saving the ice, you’re spoiling the food.

To prove this, she made prepared two identical cans, making one hole at the top and one hold at the bottom of each. The bottom hole was for drainage, and the top hole was for a thermometer. Into each can was placed an ice cube. One was wrapped in paper and the other was bare.

When a thermometer was placed in each, the one with the unwrapped ice would be colder, although the ice would last longer.

The modern student could replicate this experiment quite nicely. Even though we no longer use ice boxes in the home, the experiment demonstrates the best procedure for use in a travel cooler.  In addition to measuring the temperature inside the can, the student could compare the length of time the ice lasted.



Radio Hams Practice for War: 1941

1941MarPM
In 1941, the ham radio operator shown here was asked how long he would need to get his portable station into operation in the field. “Six minutes is the average time,” he replied. The officers asking the question were skeptical, but they watched as he opened his suitcase, hooked up a car battery, hammered in a ground stake and slung the antenna into a tree. He then tapped out a message to the control station fifteen miles away.

This was but one of the tales recounted eighty years ago this month, in the March 1941 issue of Popular Mechanics, in an article entitled “Radio Hams Practice for War.” It detailed the work of the 1800 member Army Amateur Radio System and pointed out that in time of war, thousands of trained hams would go into the military for active duty, and others would take on civilian duties such as listening for clandestine stations.

In another exercise, hams were asked, “your radio transmitter is completely smashed by a falling chimney. How long will it take to borrow an old broadcast receiver from a neighbor and build a new transmitter from its parts?” Another ham was ordered, “simulate destruction of your main transmitter. Rig up your emergency equipment and report back on the air as soon as you can.”

The article detailed a number of ways in which hams were “preparing themselves against a possible ‘M’ day.”



1946 Chicago TV

1946FebRadioRetailing2Shown here 75 years ago this month in the February 1946 issue of Radio Retailing is one Mr. O. Winter, principal of an unnamed Chicago high school, along with some of his students. This is probably the first time any of them had seen television, and they are watching a special telecast over WBKB, put on by the Radio Manufacturers Association.

The young woman at the left appears to be excited by the advent of the television age, while the young woman at the right appears somewhat skeptical of the new medium.  Below, three more students take in the experience. The young women seem to have dressed for the occasion, while the young man treats the occasion decidedly more casually.

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Home Recording: 1941

1941FebPS3The magazine also showed this commercially available record copier, with an auxiliary turntable on top of the regular turntable. A record is played on one, and an exact copy is cut by the other.

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Davey & Goliath 60th Anniversary

Today marks the 60th anniversary of Davey & Goliath, the iconic children’s religious claymation series, which premiered in syndication on February 25, 1961.

In 1958, the United Lutheran Church in America, which later became part of the Lutheran Church in America, and later the Evangelical Lutheran Church in America (ELCA), budgeted $1 million to fund production of a children’s television program. The denomination contracted with Clokey Productions, the creator of Gumby.

The resulting claymation series starred Davey, a boy who aged somewhat as the series progressed, and his dog Goliath. Goliath was able to talk, often making futile warnings about some peril Davey was about to get himself into. For some reason, only Davey was able to hear him.

Clay figures were used, but as the series progressed, the scenes became somewhat more realistic, with fabric clothing used rather than clay. Solid heads were used throughout the show’s production.  Interchangeable heads with numerous facial expressions added a somewhat realistic look to the characters.

Luther rose. Wikipedia image.

After the duo survived some adventure, the program would often conclude with a Christian moral lesson delivered by Davey’s father, although occasionally the family’s pastor would deliver a sermonette.  While I don’t believe Davey’s family had any denominational affiliation identified during the program, the Luther Rose was displayed during the credits, and the show’s theme song was A Mighty Fortress.  I’m sure there are millions who identify the quintessential Lutheran hymn primarily as the theme song from Davey and Goliath.

Numerous episodes were made until 1975. After a hiatus, the ELCA decided in 2001 to bring the characters back. To finance the project, Davey and Goliath took on part-time jobs as commercial pitchmen for Mountain Dew. They went on to star in a 2004 Christmas special.

You can find a complete history and timeline of the series at LivingLutheran.org.  For those who wish to delve deeper into the theological significance of the series, the site also offers an excellent 8-page study guide.

 



Record Storage Woes: 1941

1941FebRadioRetailing2This young woman is obviously distraught and overwhelmed, but it’s not her fault. It’s the fault of her radio-phono dealer, who neglected to sell her anything in which to store her records. She is pictured in the February 1941 issue of Radio Retailing, which reminds dealers of the potential peril, and explains that “people who buy soon have scarred and battered records scattered all over the house unless dealers simultaneously sell accessories to keep them in.”

To prevent this from happening, the magazine listed the manufacturers of a number of different racks and cabinets, any of which would have solved this woman’s problems. The next page of the magazine showed one reason why the problem was becoming acute: It was the prevalence of compact combination radio-phonos hitting the market. The player didn’t take up much space, but the records that it played represented a storage problem.1941FebRadioRetailing3

 

 



1971 EBS False Alarm

MushroomCloudFifty years ago today, the Emergency Broadcast System (EBS) sent out a warning that the nation was under attack. Thankfully, it turns out it wasn’t. A test was scheduled for that Saturday morning, but an operator at the Cheyenne Mountain complex put in the wrong tape. Instead of the tape announcing that it was only a test, he ran the tape for a real attack. It contained the code word “hatefulness” to authenticate the message.

At radio stations around the country, DJ’s ripped open the envelope next to the teletype machine containing the authenticating code. And sure enough, that was the correct code word for that day. Stations were supposed to cease normal operations and begin broadcasting information about the attack. But that information was never forthcoming.

Since a test had been scheduled, many stations suspected that there was an error, but it wasn’t confirmed officially for 40 minutes. The most famous recording from that day comes from WOWO in Ft. Wayne, Indiana, which you can hear in this video, where announcer Bob Sievers interrupted the Partridge Family with the news:

You can also listen to the event from WCCO Minneapolis at RadioTapes.com.



1961 Emergency Call Box

1961FebEI3Sixty years ago, the February 1961 issue of Electronics Illustrated showed this prototype of a highway emergency call box from Hoffman Electronics, dubbed the “safety satellite.”

The unit is self-explanatory. In an emergency, the motorist would push the appropriate button for police, fire, ambulance, or service, which would be dispatched from a central control point.

While the FCC had not yet assigned a frequency, the prototype three-tube VHF transmitterwas operating on 72-76 MHz, using FSK transmission with about 1 watt transmitter power. While the article does not specify, from the photo of the device, it appears that the message is sent by a motor-driven keyer.

It was said to have a line-of-sight range of about 25 miles. Each emergency message would transmit for 1.5 seconds, and would represent about 5 minutes charging time with the silicon solar panels. Six NiCd cells were used. On transmit, one was used to power the filaments, and the other five went to a solid-state power supply to provide the B+ voltage.

The price tag for each transmitter was about $300, with the FM receiver running an additional $250-275. Depending on the complexity of the decoding and display consoles, the monitor station could run a total of $3000.

The system was touted as a bargain, since the cost to wire a highway would be about $3000 per mile, with one transmitter every quarter mile on each side of a freeway. This compared to about $8000 per mile to install emergency telephones. When charging, the batteries would be in parallel.

In addition to emergency highway use, the system was capable of sending telemetry for industrial applications.