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Many thanks to a number of SWLing Post contributors including, Mike, Dan, Ron and Bob who all shared this article from the BBC World Service:
The bombs used by Allied forces during World War II were so large, they weakened the Earth’s upper atmosphere.
The air raids turned towns to rubble and ash, but now new research shows shockwaves could be felt up to 1,000 km above the UK.
Chris Scott, from the University of Reading said: “I was absolutely astonished [when I found out].
“Each raid released the energy of at least 300 lightning strikes.”
It’s now hoped the research will give us a better understanding of how natural forces such as lightning, volcanic eruptions and earthquakes can affect Earth’s upper atmosphere.
[…]But Chris Scott admits “these were very temporary effects which heated the atmosphere very slightly.”
[…]Chris Scott said: “This [research] is really important if we’re going to understand the ionosphere as a whole.
“We know the ionosphere is controlled by solar activity but it varies much more than can currently be explained.”[…]
Many thanks to a number of SWLing Post contributors who’ve shared a link to this excellent article by Denny Sanders in Radio World Magazine about the history of the Zenith Transoceanic:
Zenith Trans-Oceanic Radio in War and Peace
This iconic portable receiver was known for durability and quality
They say necessity is the mother of invention. Nothing proves this more than the story of how the iconic Zenith Trans-Oceanic portable radio receiver came into existence.
Commander Eugene McDonald (1886–1958), the founder of Zenith Radio, was a stickler for quality and insisted that any Zenith product represented cutting edge technology and design integrity.
He was also an accomplished yachtsman. During his many ocean voyages, he constantly was frustrated with the inability of any portable commercial radio set to perform reliably at sea. In about 1939, he ordered the Zenith R&D department to come up with a rock-solid, portable AM receiver sensitive enough to pull in signals from great distances. He insisted that the radio be a multi-band unit including shortwave, marine and aircraft bands.
The Zenith crew came up with a gem: the Trans-Oceanic, a gorgeous piece of engineering housed in a robust and dramatic cabinet designed by the brilliant Zenith industrial designer Robert Davol Budlong.[…]
A new RSGB web page highlights the role of Voluntary Interceptors in the Second World War and the crucial involvement of the Society
At the outbreak of WWII in 1939 MI5 established a unit known as the Radio Security Service (RSS) to detect and monitor enemy radio transmissions. The RSGB were approached to help pick and recruit radio amateurs with advanced Morse skills. These volunteers became known as the Voluntary Interceptors.
The former President of the Chelmsford Amateur Radio Society, Harry Heap G5HF (SK), was a Voluntary Interceptor, further information at http://g0mwt.org.uk/society/g5hf-sk/g5hf.htm
A house on the bluffs at Camp DeWolfe in Wading River, covertly used as an FBI radio transmission station during World War II to gather military intelligence, has been added to the state and national registers of historic places.
FBI radio operators impersonating German agents used the Wading River Radio Station to communicate with the German intelligence service, according to the site’s registration form with the National Register of Historic Places.
Information covertly gathered by agents at the radio station was critical to inspiring the United States’ development of an atomic bomb.
The station was also involved in the Operation “Bodyguard,” which used counterintelligence to confuse and mislead the Nazi government about the upcoming Allied invasion of Europe.
The radio station operated from 1942 to 1945.
[…]In January 1942, FBI engineers installed radio equipment in the house, hid a large antenna in the woods, and built a diesel-powered generator using an automobile engine to avoid local suspicion about electricity consumption at the house, which was far greater than what was then the norm due to the radio operations. An FBI agent assigned to manage the operation moved in with his family — and two or three radio operators. The first floor was maintained as the agent’s family home, while the second and third floors were used for the FBI operation, according to the national register registration narrative. They remained there for the duration of the war.
[…]The FBI had been looking for a spot to locate the transmission station for the spying operation and were attracted by the home’s cliffside location and the site’s remoteness. According to the national register registration document:
“By January 1942 [an FBI radio engineer] had stumbled upon the Owen House located in the tiny fishing and farming hamlet of Wading River, New York. Located eighty miles east of New York on Long Island’s North Fork the spacious three story building sat on a cliff bordered on one side by Long Island Sound and acres of dense trees on the other three sides, and the only approach to the station was a bumpy, rutted quarter mile path. Even by today’s standards the house is not easy to find. In 1942 it would have been nearly impossible.”
An FBI agent’s inquiry took the Owen family by surprise. They were sworn to secrecy.[…]
Made during WWII by RKO Radio Pictures, AIR WAVES gives a brief history of the radio, and shows the development of the technology as it progressed from a crystal set novelty to an indispensable part of American life. Radio City Music Hall and the Rockefeller Center are seen at the 2:00 mark, with the largest radio studios in the world. At 2:30, the NBC studios are seen and at 3:10 a demonstration is made of how sound effects are made using cellophane, wooden blocks, and rubber spheres. At 4:10, a studio is seen with actors rehearsing their lines, and an engineer working with the actors to make sure everything is technically okay. At 5:41, announcers Milton Cross is seen with Jack Costello and Calvin Keach. “Twin gods of radio broadcasting are the clock and the conference…” says the narrator, and at 6:00 you’ll see the discussions that lead up to the broadcast of any network show on radio (and today, on TV). At 7:15, records are played on the air, scripts are produced on steno and mimeograph machines, and all sorted… The music library is seen at 7:48 with sheet music laid out. At 8:06, all stations are notified of the latest information with the new program and a dress rehearsal undertaken. The stopwatch commands the attention of everyone, and the program is finally on the air at the 9:10 mark.
At 10:00, the film dramatically shifts to show December 7th in Hawaii, and speaks about the work of NBC to sell war bonds and promote national defense and “do its share unflinchingly”. The war effort is shown with men and women working on the air to help people working “at war” and boosting their morale. Lowell Thomas is shown at the 11:30 mark, keeping the public informed of the latest developments.
Thanks for the tip, Mike! It’s truly amazing to see the amount of effort that went into live radio broadcasts.
If you’re a regular here on the SWLing Post, you’ve no doubt discovered that I’m a fan of vintage radios.
Lately, I’ve been attempting to let go of some of my vintage gear to give my favorite rigs proper shelf space and dedicated antenna time. To keep temptation at bay when I visit flea markets or hamfests (like Hamvention and the one in Shelby, NC) I now focus on WWII era radios; specifically “morale” radios that were used for troop entertainment. I’ve two morale sets: the Scott Marine Radio Model SLRM (technically, a commercial version of a Navy set) and the Minerva Tropic Master.
I purchased this Minerva set off of eBay a couple years ago. I got it for $50 or $60, if memory serves (the seller originally wanted $180 + shipping!). He claimed it worked, but after I asked him a few questions prior to making an offer and learned that “working” meant the speaker prodeced a noise and the backlight worked. I made a low offer and he accepted.
Last year, I took Minerva over to my buddy, mentor and boat anchor doctor, Charlie (W4MEC). Charlie discovered the radio had many issues and several poorly implemented repairs. Still, in a few short weeks, when parts arrived he brought the girl back to life.
With front cover closed.
The Tropic Master is a portable eight tube receiver that covers both the AM broadcast band and shortwave bands from 5.5-18 MHz. It can be powered by AC or DC. It was “tropicalized” to withstand extreme heat and humidity. The internal speaker produces mellow, full-fidelity audio and the volume can be increased to room-filling.
The Tropic Master is portable and even has a fold down handle on top of the chassis. Though substantial, it must be the lightest of all of my vintage metal chassis radios.
Tuning isn’t exactly precise, but it does the job and is a pleasure to use. It’s quite sensitive on both shortwave and mediumwave. Last night, she was tuned to the Voice of Greece on 9420 kHz–I probably listened to two hours of Greek music while her eight tubes warmed the shack.
Who could turn down a radio with this speaker grill?
If you ever find a Minerva Tropic Master at a flea market or hamfest, I say adopt one! It’s a beautiful receiver and like all good vintage radios has a story and history of its own.
Post readers: Any other Tropic Master owners out there or do you have a morale radio? Have you ever spotted a Tropic Master in the wild? Please comment!
Many thanks to SWLing Post contributor, Kim Elliott, who recently shared the photo above of President Harry S. Truman via @RealTimeWWII.
If I’m not mistaken, that is a Scott Radio Labs Model RBO-2.
I’m guessing that’s also the speaker mounted on the wall directly above the receiver.
Scott Radio Labs marine receivers were shielded to the point that they had very low local oscillator radiation. This design prevented detection of the ship via the enemy’s use of radio direction finding gear.
