Category Archives: News

Creating a global network of inexpensive remote SDRs

U_Twente_SDR

Many thanks to SWLing Post contributor, Mark Fahey, who replies to Ivan’s preliminary review of the V3 RTL-SDR dongle:

With Shortwave SDRs (the receiver dongle) now costing less than $20, the time has come for us to set up a global group of receivers that we can all log into at will!

Have a look at SDR.hu – here you can put your SDR dongle on line and share it with anyone and they have full control of the receiver just as if it was in their own shack.

Imagine receivers scatted around the world – South America, Tropical Asia, Africa! The cost is now virtually nothing, all that is needed is the dongle, antenna (doesn’t have to be anything special – even a long wire or whip) and a small low cost CPU (Raspberry Pi for example).

Anyone else interested in this dream? Lets get together, get some receivers setup and then talk about our experience in a kick-ass presentation at the 2017 SWL WinterFest in PA!

Also… I am very soon to receive my KiwiSDR matched to a BeagleBone CPU. It will be online at SDR.hu and four remote listeners will be able to tune the full shortwave bands independently, its like my own Twente setup! Heaps of others are getting receivers online in the next few months with KiwiSDRs, this is going to be totally amazing!

I agree, Mark! While there is already quite a network of remote SDRs and receivers in the world, the barrier of entry keeps getting lower and lower. It’s hard to imagine that $25 can buy an SDR that natively covers the shortwave and mediumwave bands!

There’s only one other requirement for an online SDR that Mark didn’t mention: a decent Internet connection. Sadly, this is the only thing keeping me from hosting a remote SDR here at my home. I considered purchasing a KiwiSDR like Mark, but my upload speed (0.2-0.3 mbps) is so terrible and so unreliable that I could only host one listener at a time at best. You can bet that as soon as my ISP upgrades our service, I’ll launch a web SDR as well.

Of course, I’m willing to bet that most SWLing Post readers have more than enough bandwidth to host a $25 remote receiver! Let’s make Mark’s vision a reality!

Ivan’s preliminary review of the new RTL-SDR dongle on shortwave/mediumwave

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RTL-SDR-RTL2832U-e1471375714199 Many thanks to SWLing Post contributor, Ivan Cholakov (NO2CW), who shares the following video review of the new RTL-SDR dongle on the shortwave and mediumwave bands.

Ivan notes:

This is daytime reception comparison. Nighttime could be a different picture. [The RTL-SDR dongle] tunes and frequency is 100% on spot.

Using SDR Sharp you have several AGC settings to play with and find the best combination. The best setting seems to vary with band and signal strength.

The [SDR receiver] comes with a short (20 cm) and long (120cm) telescopic antennas. Neither one is usable for HF or Medium wave.

When ordering the radio you have to get a USB extension cord for the dongle. When plugged in directly into a laptop and then antenna coax it can become bulky. You also will most likely need an SMA adapter to BNC and SO 238.

I hope this helps.

Click here to view on YouTube.

Many thanks for sharing your video, Ivan! For a $25 SDR, I’m pretty impressed so far! I’m also very curious how it will hold up to stronger nighttime signals and, especially, adjacent signal interference. I imagine it may be prone to overloading as well. Please keep us posted!

Have any other Post readers tested the new RTL-SDR dongle on HF? If so, please comment!

Shortwave Radio Recordings: Radio Baghdad, August 8, 1990

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radio baghdad qsl

Many thanks to SWLing Post contributor, Al Quaglieri, who shares the following recording, QSL (above) and notes:

Here’s a nice recording I made of the first 13 minutes of Radio Baghdad’s English broadcast one day around August 8, 1990. It begins with some music and then there’s a newscast. For a couple of months, I sent such recordings down the phone line to CBS News in New York, who were eager to hear them. This, alas, is the only one I kept. Hard to believe it was nearly 26 years ago.

My how that does bring back memories! Thank you for sharing this excellent recording, Al!

Francis loves the Sony ICF-SW11

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Sony_ICF-SW11_4

Many thanks to SWLing Post reader, Francis, who left the following reply on our Battery Endurance Contest Results post:

Dear Thomas,

I have been using a Sony ICF-11 for 5-6 years now, still sold new at 50-70 euro. It’s analog and rather well featured: FM (stereo on earbuds), LW, AM, and 9 SW bands. It runs on 2 cheap AA batteries I get in low-cost supermarket, for sure not the best ones.

Using it at least one hour a day on the speaker, I have to change the batteries after 9-12 months. I am convinced a set of good Duracell or Energizer batteries would last some more months.

I am not a radio expert, but I am quite pleased with its audio performances, specially on LW (used most of the time ) and AM, where it is vastly superior to my Tecsun PL-660. SW looks OK for what I can say from listening quite occasionally these bands. I would be curious to see a serious review of this Sony to know how it compares with others, but I didn’t find any on the web so far (hint?). [Yes, Francis, hint taken!]

I am so pleased with this small radio that I recently bought a second one as a spare.
Thanks for your very interesting blog and reviews.
Francis

Thank you, Francis, for sharing your thoughts on the Sony ICF-SW11 and your photos as well!

It appears Amazon.com (US) has a few options for ordering a Sony ICF-SW11–click here to show search results. Prices vary between $50-$55; Amazon even has replacement telescopic whips available.

Of course, an eBay search will also uncover a number of SW11’s.

I searched the web, but couldn’t find many other retailers selling new ICF-SW11’s. It appears many of the ones on Amazon are imports from Japan.

At $50 shipped, it seems like a bargain to me, so I just pulled the trigger on one.

BBC Monitoring: A tour of Caversham Park

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HalliDial
(Source: Southgate ARC)

A tour of Caversham Park before it closes – the home of BBC Monitoring – a historical BBC World Service department which has been monitoring some of the world’s most seismic events for 75 years

Caversham Park became the BBC Monitoring Headquarters in 1941 and in light of recent news that, due to a £4million pound funding cut, it’ll be closing its doors for good, Rajan Datar visits the iconic building.

Coordinating Editor, Chris Greenway gives a tour of the building and a sense of its history, while Lina Shaikouni gives a taste of what the service provides today.

Over to You – The Home of BBC Monitoring
http://www.bbc.co.uk/programmes/p044jj9h

First broadcast on Saturday, August 20 the podcast should now be available at
http://www.bbc.co.uk/programmes/p002vsn8/episodes/downloads

Battery Endurance Contest Results: Sangean DT-160CL vs Sony SRF-39FP

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On August 4, 2016, the same day I received my new Sangean DT-160CL, I popped a fresh set of CVS Max Alkaline batteries into the DT-160CL as well as into my trusted Sony SRF-39FP. The mission? To see which radio could perform longest on a set of batteries.

I set my stopwatch as I turned on both radios, tuned to the same frequency, set the volume to the same levels…and waited.

And waited. And waited. And as I waited, I posted updates.

But at last, the waiting is at an end: here are the contest’s final results.

Sangean DT-160CL: Impressive Performance

On August 9, I reported that the Sangean DT-160CL finally threw in the towel, logging an impressive 116 hours 30 minutes of operating time–!

Without a doubt, this is one of the longest run times I’ve ever experienced from an AM/FM radio with digital display.

Interestingly, the day after the DT-160CL shut down, I turned it back on, and it operated for an additional 45 minutes or so, obviously absorbing a little more voltage from rested cells. During that 45 minutes period of time, the audio and overall performance was respectable. No doubt the DT-160 shuts down before audio is terribly compromised.

Sony SRF-39FP: The Endurance King!

Amazingly, the Sony SRF-39FP kept running well beyond 116 hours. Well beyond…

By Wednesday morning–one full week from the time I began the endurance contest–the Sony SRF-39FP finally began showing signs of low-voltage: the audio had a small amount of splatter and sensitivity began to be compromised.

Unlike the Sangean DT-160CL, which clearly has a cut-off voltage, the SRF-39FP kept milking the battery for its last vestiges of power.

I decided that I would call a “time of death” for this AA battery when the Sony struggled to receive local AM stations, as well as transmission from my in-house SStran AM transmitter.

This happened approximately 163 hours and 54 minutes into its marathon run.

This stopwatch app tracked the full endurance test. I pressed “stop” when the Sony SRF-39FP finally gave up.

Wow, wow, wow. I simply had no idea any portable could operate almost one full week on one AA cell–!

In truth, I’m sort of relieved the ’39FP finally gave up the ghost. I was beginning to think the thing was powered by some supernatural force…

When I started this test, I thought the Sony SRF-39FP was rated for about 40-80 hours of run time on a single battery. I couldn’t remember where I got that number until I recently re-read this article from The New Yorker, which highlighted the 39FP’s role in correctional facilities:

“The SRF-39FP is the gold standard among prison radios in part because it runs on a single AA battery, and offers forty hours of listening time…”

Wait, just forty hours? Perhaps from the cheapest AA battery made…

With an advanced chemistry cell like the Duracell Quantum or Energizer Advanced Lithium series, you’ll clearly get three to four times that performance.

DX mode

And here’s the thing: I’m convinced I could’ve gotten much more time out of the SRF-39FP.

Like similar Sony portables, the SRF-39FP has a “DX/Local” switch. When set to DX, the receiver is made to deliver maximum performance.

If you’re listening to a local station, however, “Local” mode is a better choice. You’ll still be able to receive your target station, yet draw much less from the battery.

I left the Sony SRF-39FP in “DX” mode for the entire battery endurance test. Had it been in “Local” mode, I believe I’d be reporting an even longer run time. How much longer, I don’t know, but you can bet that my curiosity will soon get the best of me…I plan to do a separate endurance test to find out.

Clear choices for battery longevity

Sangean-DT160CL and Sony SRF-39FP No doubt, our little test has proven that radios marketed to the prison system do offer excellent battery performance.

Now I’m very curious whether the standard Sangean DT-160 will offer the same battery performance as its clear-cased counterpart, the DT-160CL. The only difference in the two appears to be that one offers a clock, while the other doesn’t. I wonder if that would have any significant difference on battery life.

Additionally, the Sony SRF-39FP has shown us that analog receivers can be much more efficient than their digital counterparts. We’ve known this a long time at Ears To Our World, and which is why almost all of the radios we supply to schools in remote, rural locations are analog.

Sadly, analog radios are getting much more difficult to find these days as DSP-based receivers have become more affordable to produce.

The Sangean DT-160 is available at Amazon.com and Universal Radio. The Sangean DT-160CL (the version tested) is available through Amazon.

Click here to search eBay for the Sony SRF-39FP.

Readers: Know of any other battery-miser radios? Please comment!

Radio South Atlantic: recording of a short-lived clandestine radio station

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Crosley-Dial-BlackAndWhite

In reply to our recent post about Radio Atlantico del Sur, SWLing Post contributor, Jonathan Marks, adds:

Radio South Atlantic was a short-lived clandestine radio station started by the UK Ministry of Defence with programmes aimed at Argentine troops on the Falkland islands. This programme was broadcast from a transmitter on Ascension Island which was temporarily taken away from BBC World Service.

The Falklands War (Spanish: Guerra de las Malvinas), also known as the Falklands Conflict, Falklands Crisis and the Guerra del Atlántico Sur (Spanish for “South Atlantic War”), was a ten-week war between Argentina and the United Kingdom over two British overseas territories in the South Atlantic: the Falkland Islands and South Georgia and the South Sandwich Islands. It began on Friday 2 April 1982 when Argentina invaded and occupied the Falkland Islands (and, the following day, South Georgia and the South Sandwich Islands) in an attempt to establish the sovereignty it had long claimed over them.

On 5 April, the British government dispatched a naval task force to engage the Argentine Navy and Air Force before making an amphibious assault on the islands. The conflict lasted 74 days and ended with the Argentine surrender on 14 June 1982, returning the islands to British control. In total, 649 Argentine military personnel, 255 British military personnel and three Falkland Islanders died during the hostilities.

This is a studio copy of Radio South Atlantic. In May 1982, the British government decided to set up a Spanish language radio station targeting Argentine troops. This was probably in response to an Argentine radio station (nicknamed Argentine Annie by the UK press) which appeared on shortwave some weeks earlier using the Beatles theme “Yesterday” as a signature tune.

I was editing the Media Network programme at the time. We could hear Radio South Atlantic in Hilversum – but the signal was very weak. So I rang the British embassy in the Hague and asked if it would be possible to get a studio copy of the programme to use in a documentary feature we were making. A few days later, a courier riding a large motorbike arrived at RN’s reception and asked for me. I went down to the front-desk to sign for the tape. “But you can’t keep this tape. You can only listen to it” was the message from guy in the helmet. “I have to take it back to the Hague in about half an hour”. I said I’d look for an empty studio, gave the guy a large coffee and wandered casually round the corner. Then I made a mad dash to the fast copy-room used to make tape copies of RNW transcription programmes for other radio stations. It had a machine that could copy tapes at around 8 times faster than normal. Luckily, Jos, the guy in charge, saw my challenge, set up the machine immediately and 15 minutes later I was back in reception to return the tape to the messanger. And I had a copy.

It seems the British dropped leaflets over the Falklands to try and spread the word that this shortwave radio station existed. And we later analysed the programme. It was classic Sefton Delmer (Black Propaganda), although rather poorly presented. Bit like calling up Vera Lynne if the British had a dispute with France.

But this is one of the few surviving recordings of Radio South Atlantic. You be the judge of how effective it all was. http://jonathanmarks.libsyn.com/radio-south-atlantic-may-1992

Click here to read Jonathan’s full post about Radio South Atlantic and listen to the recording on his website.

This is an amazing recording, Jonathan. I’ll admit that I had never heard of Radio South Atlantic before and never knew a UK-supported clandestine station was on the air during The Falklands War/Guerra de las Malvinas.

Thanks for the excellent history lesson and your own (clandestine) recording!