Author Archives: clem.law@usa.net

Notre Dame de Paris Sound System & Air Raid Sirens

2019 fire. Wikipedia photo: LeLaisserPasserA38 [CC BY-SA 4.0], via Wikimedia Commons

Construction of the Cathedral of Notre-Dame de Paris, which is burning today, began in 1160 and was largely completed in 1260. It was wired for sound in about 1925, as shown in the illustrations above. At left, a microphone is visible above the pulpit. At right, a speaker is mounted on a pillar near the chancel. One of the cathedral’s distinctive rose windows is visible in the background. The pictures appeared in the July 1925 issue of Radio News, which reported that the then-700-year-old cathedral had finally been modernized. According to the magazine, the speakers were installed “so that the congregation may hear the services.”

Another picture, shown below, is also of Notre Dame, but is not immediately recognizable as such. From the 1918 issue of Electrical Experimenter, the picture shows air raid sirens installed atop one of the towers. For an look at a 1914 air raid on Paris, see our earlier post.

Arnie Coro, CO2KK, 1959

Castro in Washington, 1959. Wikipedia photo.

Sixty years ago today, on April 15, 1959, Cuban dictator Fidel Castro began his eleven day tour of the United States. But as you can see from the page of that month’s Popular Electronics shown above, another familiar Cuban name was making his mark in the U.S.

The article is a one-page feature on TV DX’ing, and offers little detail. The image at the top is a screen shot of WPST-TV in Miami, captured in Havana, Cuba. And the author of the article is none other than Arnaldo “Arnie” Coro, Jr., CO2KK, one of the founders of Radio Havana Cuba, and a popular host of the station’s DX program.

Sentinel Model 170-BL, 1939

Eighty years ago this month, the April 1939 issue of Radio Retailing carried this ad for Sentinel portable sets, featuring the country’s lowest priced battery set, the model 170-BL. The three-tube superhet sold for $14.95, including battery, and featured a tube lineup of 1N5G, 1N5G, and 1A5G. Filaments ran off a 1.5 volt A battery, with a 90 volt B battery.

Henry L. Carter, Jr., W8FTB

Shown here in the April 1934 issue of Short Wave Craft magazine is the well equipped station of Henry L. Carter, Jr., W8FTB, 45 Sheldon Terrace, Rochester, N.Y., at the time, the youngest licensed amateur in the United States. Carter was first licensed at the age of 10 on January 14, 1932. He got his first station set up with the assistance of his father, ex-8BOW, who had been licensed in 1923. The transmitter was a crystal controlled three tubes on 3530 and 3840 kHz. Carter reported that he could copy “20 per, and send ‘plenty fast.'”

He had worked stations throughout the U.S., Canada, and Mexico, and held an Army Amateur Radio Station appointment. He was also the youngest member of the Scout Amateur Radio Net, and as you can see from the uniform, he kept himself busy with Scout work. His troop had organized a radio club consisting of sixteen members.

According to a Sept. 27, 1939, article in the Rochester Times Union contained in this scrapbook,
Carter, then residing at 297 Plymouth Ave. S., joined the Army Signal Corps at the age of 18.

I wasn’t able to find any reference to Carter after the War. If he had gone back to Rochester, his call would have become W2FTB, but I wasn’t able to find any reference to him holding that call. He would be about 97 today, so if Mr. Carter or a relative is out there, we would enjoy very much hearing from you to follow up.

1944 Kiddie Tractor

Shown here, from the April 1944 issue of Popular Mechanics, is the son of Robert C. Cross of 507 Main St., Woodland, California. The elder Mr. Cross built the 240 pound Caterpillar-type tractor for the young man, who undoubtedly had lots of fun driving around with the 3/4 horsepower engine.

Steering was accomplished the same way as a full-size tractor, with clutches and brakes on the rear axle controlled by levers. The cab also featured a throttle and choke control, as well as a cut-out switch. Mr. Cross reported that the cost of the tractor was about $125.

The younger Mr. Cross would be in his 80’s today, and since we know that people like to Google their own names, it’s not inconceivable that he is reading this. If you are, we would love to hear from you with your recollections of this most interesting toy.

1949 Two Tube Broadcast Receiver

Seventy years ago this month, the April 1949 issue of Popular Mechanics showed how to put together this simple two-tube broadcast set. Running off AC power, the set would drive a loudspeaker. It used many of the same parts as a one-tube set published in the January issue, allowing the radio student to upgrade the simpler set.

A 6J6 dual triode carried out the RF duties, with a 6AK6 pentode AF amplifier driving the speaker. The set employed a selenium rectifier.

One unobtainium part is the permeability tuner, similar to the one used in a 1948 Popular Science receiver.

Milwaukee Radio Listings, April 10, 1944

Here’s what was on the radio 75 years ago today. These listings appeared in the Milwaukee Journal, April 10, 1944 and show programs for April 10 and 11. (You can click twice on the image above for a larger version.)

Wartime Tube Substitutions

During World War II, many radio tubes were unavailable, and the magazines were full of ideas on how to cope. The April 1944 issue of Popular Mechanics showed how to make adapters to use similar tubes that might be available, but used different base types.

In particular, the magazine pointed out that loctal tubes were often available. Therefore, the adapter shown here allows a loctal tube to be plugged into a standard octal socket. The bottom half of the adapter was a defunct tube (probably the one being replaced), and the top half was a socket to match the new tube.

Eclipse of April 8, 2024

2024 Eclipse Path. NOAA image.

As we did in 2017, OneTubeRadio.com will provide full coverage of the April 8, 2024, total solar eclipse.

This is exactly five years from today. Little preparation is needed at this point, but you should make a mental note to travel to the path of totality, which is less than a days’ drive from most of the United States. The total eclipse will be visible in parts of Texas, Oklahoma, Arkansas, Missouri, Illinois, Indiana, Ohio, a tiny piece of Michigan, Pennsylvania, New York, Vermont, New Hampshire, and Maine. The path of totality also passes through Mexico and Canada. Major cities in the path of totality include Dallas, Little Rock, Indianapolis, Buffalo, Cleveland, and Montreal.

The eclipse will take place on a Monday. For the 2017 eclipse, we made our hotel reservations about a year in advance, and paid the normal rate with plenty of availability. So if you plan on booking in April 2023, you should have many options. Also, in late 2023 or early 2024, you should order your eclipse glasses.

If you have kids who will be in school, plan on taking them out of school that day. Unfortunately, the 2017 eclipse showed that American schools had an irrational fear of the eclipse and actively prevented children from witnessing it. If you believe that your child’s school is more enlightened, then on the first day of the 2023-24 school year, you should have your children ask the science teacher if the school is planning a field trip to see it. If the teacher balks, then your children should let him or her know that they will be absent the day of the eclipse.

This is an entirely reasonable request for most schools. For example, students in Chicago could be placed on a school bus and taken to see the eclipse only a couple of hours’ drive away in Indiana. The expense will be less than other field trips taken to amusement parks, movies, etc. This is true for schools in many cities. They have the opportunity to let the kids witness an amazing scientific event, but only if they do some basic planning.

But I predict that this won’t happen, since most schools won’t think of the possibility until after it’s too late to make the necessary plans, or they’ll have the same irrational fears that showed up in 2017. It’s the duty of the students to pester the administration so that the necessary plans are made sufficiently in advance. And as I explained in 2017, if the school fails to act, then it’s reasonable for children to skip school on April 8, 2024.

Diozo Phone Disinfector, 1909

A hundred ten years ago this month, the April 1909 issue of Popular Electricity carried this ad for the Diozo Phone Disinfector, produced by the Parker Chemical Co. of 233 Market Street, Chicago. (The address no longer exists, since Market Street disappeared and became part of Wacker Drive.)

The ad, confirmed by scientific tests, warns that the mouthpiece of every telephone swarms with malignant germs, including tuberculosis, diphtheria, typhoid, or pneumonia. There might even be more revolting diseases lurking there! Fortunately, to avoid the harm, all you need to do is slip the diozo phone disinfector on the mouthpiece. Diozo is apparently a disinfectant that works in its solid form to somehow kill germs.

But according to this article published just a few months later in the California State Journal of Medicine, the State Hygenic Laboratory (of California, presumably) questioned some of the claims made by the company. After being challenged, the company noted that to be effective, the Diozo must be crushed and mixed with water, which would make its use on a telephone somewhat problematic.

Strangely enough, the Diozo Phone Disinfector doesn’t appear to be available today. But if you search Amazon for “phone disinfector,” you can chose among the following products: