The Birth of Radar Memorial

Photo by Amanda Slater

Many thanks to SWLing Post contributor, Paul Evans, who writes:

Interesting article on the new monument to radar between Daventry and Towcester in Northamptonshire, UK.

https://www.atlasobscura.com/places/birth-of-radar-memorial

Legend has it that this was conducted around 25-28 MHz, which was the very top end of higher power RF at the time.

The location sits closer to Towcester, although the event is always quoted as having taken place at Daventry (the source, not the receiver).

It’s fascinating that Plessey Research Caswell was set up almost immediately, not very far away and was heavily involved in radar and other solid-state research through to the 1990s.

[Disclosure: the author (Paul) worked at Plessey Caswell and was Two Terminal device Manager at Plessey Microwave, Towcester in the 1980s]

Many thanks, Paul, for sharing this fascinating bit of history.

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Radio Canada International at 75 years

(Source: RCI.net via David Iurescia)

Today is an auspicious day for RCI. It was February 25, 1945 that the CBC International Service began shortwave broadcasting to Europe. It was designed at the time to provide accurate news to occupied areas in

English French and German, and to provide news from home for the huge contingent of Canadian military personnel serving and fighting in the Second World War.

Since then the “IS” has gone through a variety of changes, including the name which was changed to Radio Canada International in 1970. It has been through several moves, from its first location in a former brothel, to the converted Ford Hotel a few years later, to rented office tower space, to the main headquarters of the French service, Radio-Canada.

It has also gone through a number of language-service changes, from 14 languages during the cold war broadcasting to formerly free countries then under the control of Moscow, to its current five languages, Mandarin, Spanish, Arabic, English and French.

Other changes include the drastic cuts of 2012 which saw some 80 per cent of staff cut and the cessation of shortwave to become its current online operation.

Throughout it all RCI continues to inform on Canadian issues including political, scientific, cultural and societal and provide Canadian viewpoints and positions on world affairs.

Click here to read the full article at RCI.net.

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From the CIA Archives: An HF Spaced Loop Antenna for Direction Finding

Many thanks to SWLing Post contributor, Grayhat, who shares the following:

I stumbled upon a document I found in the “CIA reading room”:

https://www.cia.gov/library/readingroom/docs/CIA-RDP76-00451R000200010013-1.pdf

In short, the document, titled “HF SPACED LOOP ANTENNA” and dating back to 1967, describes the design of a “direction finding” antenna used to find an HF transmitter. The document describes a number of setups tried during initial experimentation and then explains the reasons for the selection of what’s called a “Coaxial spaced loop in vertical opposition”, basically two vertical loops connected in anti-phase; the document describes in detail the loop and some circuitry used with it, but the most interesting section is the one which deals with radiation lobes. if you look at that you’ll suddenly realize using such a configuration, the resulting antenna acts as a huge dipole with extremely deep nulls !!

Fascinating! Thank you, Grayhat.

And, honestly, there’s enough material in that CIA document to please the most demanding of antenna nerds! Most impressive. I’m curious if anyone has ever built one of these. If so, please comment with your experience!

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Tecsun PL-365 scanning question

Many thanks to SWLing Post contributor, Julien, who writes with the following question:

First, thanks for your site !

I have a question about PL-365. It seems auto-scan works only in the range of 2,245-21,950 kHz. The ranges from 1,711-2,245 and 21,950-29,999 can only be scan manually.

Do you know the reason for this? Or a trick to auto-scan the other two ranges?

I do not know the reason for the auto scan limits, but imagine it could be a limitation of the SiLabs DSP chip inside–although this is merely a guess. My hope is that someone in our community can verify or perhaps help if they know of a work-around. Please comment!

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FTIOM & UBMP March 1-7 & Special Marathon

Special 12-Hour Marathon of From the Isle of Music and Uncle Bill’s Melting Pot
March 4 0800-2000 UTC:
On Wednesday, March 4, Radio Channel 292 from Rohrbach Germany will present a special 12-hour marathon of From the Isle of Music and Uncle Bill’s Melting Pot on 6070 Khz from 0800 to 2000 UTC. There will be a special e-QSL for reception reports for the marathon.

From the Isle of Music, March 1-7:
This week, our special guest is Daymé Arocena, who will converse with us in English about her beautiful new album, Sonocardiogram.
The broadcasts take place:
1. For Eastern Europe but audible well beyond the target area in most of the Eastern Hemisphere (including parts of East Asia and Oceania) with 100Kw, Sunday 1500-1600 UTC on SpaceLine, 9400 KHz, from Sofia, Bulgaria (1800-1900 MSK)
If you don’t have a shortwave radio or are out of range, you can listen live to an uplink from a listening radio in the Netherlands during the broadcast at
http://websdr.ewi.utwente.nl:8901/?tune=9400am
2. For the Americas and parts of Europe, Tuesday 0000-0100 (New UTC) on WBCQ, 7490 KHz from Monticello, ME, USA (Monday 8-9PM EST in the US).
If you don’t have a shortwave or are out of range, you can listen to a live stream from the WBCQ website here (choose 7490): http://www.wbcq.com/?page_id=7
3 & 4. For Europe and sometimes beyond, Tuesday 1900-2000 UTC and Saturday 1200-1300 UTC on Channel 292, 6070 KHz from Rohrbach, Germany.
If you don’t have a shortwave radio or are out of range, you can listen live to an uplink from a listening radio in Europe.
Visit our Facebook page at https://www.facebook.com/fromtheisleofmusic

Uncle Bill’s Melting Pot, March 1 and 3:
Episode 153 takes us to Serbia.
On WBCQ only, there is a second half-hour featuring one of the first episodes of our show in 2017.
The transmissions take place:
1.Sundays 2200-2300 NEW UTC (6:00PM -7:00PM Eastern US) on WBCQ The Planet 7490 KHz from the US to the Americas and parts of Europe
If you don’t have a shortwave or are out of range, you can listen to a live stream from the WBCQ website here (choose 7490): http://www.wbcq.com/?page_id=7
2. Tuesdays 2000-2030 UTC on Channel 292, 6070 KHz from Rohrbach, Germany for Europe.
If you don’t have a shortwave radio or are out of range, you can listen live to an uplink from different web SDRs in Europe.
Visit our Facebook Page at https://www.facebook.com/UncleBillsMeltingPot

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Jesse’s DX-390/ATS-818 modifications

Many thanks to SWLing Post contributor, Jesse (W9JES) who writes:

I’ve been busy enhancing my Radio Shack DX-390. I added an IF-Out jack for my SDR, changed out the light for a LED, added a latch circuit for the light switch, added static protection, and disabled auto-mute. My blog with full instructions is at www.w9jes.com

Thank you, Jesse!  Here are links to the various modifications Jesse has documented:

Click here to check out Jesse’s website.

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Mystery Solved: Readers identify curious interval signal

Yesterday, we published a post asking SWLing Readers to help Brian (W9IND) identify an elusive interval signal (click here to read that post).

We received dozens of replies–thank you so much!

Many readers immediately identified the tune as some sort of utility station placeholder for Point To Point communications. Turns out, they were correct.

Many thanks to Dean Bianco who was the first reader to solve the mystery.

Dean discovered that the interval signal was for the Voice Mirror of the PTT Habana, Cuba.

Dean verified it via Rainer Brannolte ‘s excellent website, UtilityRadio.com.

Here’s the audio clip from Rainer’s website:

Here’s a link to the PTT Habana Cuba page which also includes two other audio clips of the PTT service.

Rainer even includes a scan of his verification letter:

Click to enlarge (Source: Rainer Brannolte)

This morning, I received a number of responses from readers confirming PTT Habana–thank you so much!

Not only have we helped Brian ID the station, but now there’s also one less UNID audio sample on the Shortwave Radio Audio Archive.

In addition, I’m sure my friend Greg Shoom–who originally posted the recording–would be very pleased with this community effort.

Now I need to find some more shortwave archive mysteries to solve!

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