Category Archives: SWLers

London Shortwave’s innovative PocketCHIP-powered field portable SDR

Many thanks to SWLing Post contributor, London Shortwave, who recently shared his latest SDR project: a field-portable, ultra-compact, SDR spectrum recording system based on the PocketCHIP computer.

London Shortwave has built this system from the ground up and notes that it works well but is currently limited to the FunCube Dongle Pro+ at 192 kHz bandwidth. There is no real-time monitoring of what’s being recorded, but it works efficiently and effectively–making spectrum captures from the field effortless. The following is a video London Shortwave shared via Twitter:

Click here to view via Twitter.

The PocketCHIP–the device his system is built around–is a $69 (US) handheld computer with color display:

Click here to view the PocketCHIP website.

I think this field portable SDR system is absolutely brilliant!

Homegrown innovation

London Shortwave has done all of the coding to make the FunCube Dongle Pro + work with the PocketChip computer. Even though live spectrum can’t be monitored in the field, the fact that it’s making such a clean spectrum recording is all that really matters.

All London Shortwave has to do is head to a park with his kit, deploy it, sit on a bench, read a good book, eat a sandwich, then pack it all up. Once home, he transfers the recording and enjoys tuning through relatively RFI-free radio.

A very clever way to escape the noise.

The kit is so incredibly portable, it would make DXing from any location a breeze. You could easily pack this in a carry-on item, backpack or briefcase, then take it to a park, a national forest, a lake, a remote beach–anywhere.

What I really love about this? He didn’t wait for something to be designed for him, he simply made it himself.

Thanks again, London Shortwave. We look forward to reading about your radio adventures with this cool field SDR!

DXing in a large suburban garden with the Eton Satellit & Bonito MegActive MA305 antenna

Hi there, the garden at my house is pretty small and as a consequence, I am very limited in terms of what antennas I can usefully employ. You can’t position anything further than about 10 metres from the brickwork and to compound this, we are surrounded on all sides by neighbours in close proximity. All very nice people, but all very noisy – electrically speaking lol. I simply can’t get far enough away from these sources of electrical noise to achieve excellent SNR.

The solution to my problem was ultimately a Wellbrook ALA1530 magnetic loop, but prior to that I used an end-fed random wire, the performance of which deteriorated as the months went by as the ubiquitous blanked of local QRM continued to increase. Eventually, I was forced outdoors, well away from my town – effectively catalysing my forays into the Oxfordshire countryside on DXpeditions. That first experience of listening to the radio on shortwave, in the absence of any QRM was enlightening to say the least and of course, subsequently, DXpeditions have become a mainstay of my listening activities. However, despite enjoying some great DX successes out in the woods, one has to be realistic about how often it’s possible to leave the house just to listen to the radio. This led me to the purchase of the Wellbrook ALA1530 magnetic loop. It proved to be a triumph of electrical noise mitigation and an absolute necessity in copying transatlantic medium wave signals in such a noisy and compact space. A total game-changer. The brilliant performance of the Wellbrook eventually led to me purchase a second, cheaper active antenna; the E-field Bonito Boni Whip and in turn, that purchase led me to the MegActive MA305, kindly supplied by Bonito themselves for objective testing.

Have DXing kit, will travel…everything you need in a small flight case…

You might remember my initial tests at home confirmed, as expected, that E-field antennas don’t work well in electrically noisy environments (except at LW frequencies in my experience) but outdoors, away from noise, they are superb. I have a number of reception videos on my YouTube channel – Oxford Shortwave Log which clearly demonstrate identical performance of the Bonito MegActive MA305 antenna and Wellbrook ALA1530 magnetic loop out in the woods. So, what if you’ve got a large garden in a suburban area that allows you to be just far enough from sources of electrical noise…how much of a difference does it make to the noise floor of your receiving equipment? Can E-field antennas such at the Bonito MegActive MA305 do the job? Furthermore, how well does a random wire work in a larger garden?

 My MegActive MA305 antenna system for mobile DXing…and another use for a washing line…

I was fortunate enough to know someone who owns a house with a large garden, quite close to my QTH (a 10 minute walk) and who was more than willing to let me set up my DXing equipment and sit around until the early hours of the morning, listening to and recording various signals on my Eton Satellit. In preparation, I set up the Bonito MegActive MA305 antenna and hung the radiating element on the washing line – sounds ridiculous but actually worked very well, placing it about 2.5 metres above the ground. I also set up a 40 metre longwire, which at its closest point, was still approximately 25 metres from the house, and 30 metres from the neighbours. This post will focus on the performance of the MA305; a subsequent post will detail the performance of the longwire.

The large garden I ‘borrowed’ for my DXing session with the Bonito MegActive MA305 antenna

Suffice to say, the MegActive MA305 performed admirably during my first listening session. In the middle of the afternoon I copied a very strong signal from The Voice of Korea around 15:44 hrs UTC on the 25 metre broadcast band, followed at 17:10 hrs UTC with a superb signal from The Voice of the Broad Masses 2, Eritrea, on the 40 metre ham band. Later on in the evening I copied Radio Mail with excellent modulation, CHU Canada with voice announcements (almost impossible at home), Myanmar Radio with an untypically strong signal and XEPPM Radio Educación from Mexico City with a signal I would normally expect on a DXpedition-proper with a large antenna.

My conclusions to this experiment are simply that E-field antennas can work in a suburban environment, if you are able to site them far enough away from adjacent sources of electrical noise. I don’t have empirical data on this, however, I can confirm that 10 metres proximity is too close at my QTH and 30 metres is sufficiently far away at this test location. One has to assume the houses nearby are similarly equipped to mine with electrical appliances that generate electrical noise. Thus, if you’re interested in a very well-priced, compact antenna and you live in an urban or suburban environment with access to a large garden/ outdoor space, an E-field Boni Whip or MegActive MA305 might well be suitable – and you’ll have a superb portable antenna for those listening sessions away from home!

Finally, I should mention the Eton Satellit. Much-maligned in certain quarters when it was first introduced into the market, it continues to demonstrate superb DXing credentials. I won’t forget some words of wisdom from a friend of mine and fellow DXer, with more than 3 decades of experience in listening to the bands on HF. He told me that Judging from his own experience with some of the original Grundig Satellit models of the 1980s and early 90s (namely the 400, 500 and 700) he was quite sure that the Eton Satellit is a considerably better DX performer than those vintage sets, that offered great sound for casual listening to international broadcasters, but didn’t perform too convincingly on weak DX signals. The Eton Satellit has been a revelation and I’m pleased to have played a small part in turning around the rather widely held view that it was less than worthy of the Satellit branding.

Fresh out of the box, the Eton Satellit has surpassed all my expectations…

Please find embedded reception videos below and text links to the Oxford Shortwave Log YouTube channel. My next post on this subject will cover the performance of a 40 metre longwire in this large garden environment. Thank you for reading/watching/listening and I wish you all great DX!


Click here for video on Oxford Shortwave Log

 

Click here for video on Oxford Shortwave Log

 

Click here for video on Oxford Shortwave Log

 

Click here for video on Oxford Shortwave Log

 

Click here for video on Oxford Shortwave Log

 

Click here for video on Oxford Shortwave Log

 

Click here for video on Oxford Shortwave Log


Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.

Ed gives this Realistic DX-440 a bath!

Many thanks to SWLing Post contributor, Edward Ganshirt, who shares the following:
I found this critter [a Realistic DX-440–see photo above] at a flea market. At first I pondered as to when I had my last tetanus shot before handling it, then again it had something that I see rarely in these portable radios … a BFO..!

I always said that a shortwave radio without a BFO is like a Harley-Davidson with a top speed of 25 mph, so I bought it. On the way home I could smell a barnyard aroma. I ruled out chicken and hog but I think it could have been sheep or goat. So I decided to see how well it works. It took a little bumping around with loose connections to get it working. But first since it was going to be taken apart to service the case and knobs would get a nice hot bath in a sudsy ammonia citrus cleaner with a bristle brush. Also the PCB’s would get brushed down with a mixture of denatured alcohol and acetone.

Now for the hard part: finding the rickety connections. This turned out to be simple, just inspect each wire at attachment point. I found 3 broken wires that were re soldered. Now it is together I am looking for a 9 inch antenna. The one here is not original it extends 66 inches.

As to it’s performance, This Hogg can go up to 75mph now that I have the plug wires on. The user interface speaks to me as a lab instrument more than a daily listener which I think will become its role.


Absolutely amazing transformation, Ed!

I’m especially pleased to see you’ve given this level of TLC to a Realistic DX-440. I regret having ever sold mine as it accompanied me across the ocean when I studied in Grenoble, France, for a year just after high school.

The DX-440 and I did a lot of travel and a lot DXing together! I hope your DX-440 takes you across the globe, Ed!

Paul Walker featured on VOV webite

(Source: Voice of Vietnam)

US listener: “Personal connection makes me want to listen to VOV”

(VOVWORLD) – The Voice of Vietnam (VOV) turns 72 this Thursday. Over the past 7 decades, VOV has served as a bridge linking Vietnam with people all around the world. Paul Walker, an American radio presenter and a loyal listener of VOV, says it is the personal connection that makes him want to listen to VOV and learn about Vietnam.

After a 6-hour drive from Washington we reached a small town in Pennsylvania near the border with Canada. It was a peaceful, quiet place with houses dating back more than 100 years. Paul Walker, a young radio presenter, met us in front of his house with his radio gears already set up.

With a small table and chair, 2 antennas, an analogue receiver, a tuner, and a digital recorder, Paul finds it interesting to listen to foreign radio programs. Paul said he picked up an obsession with radio when he was a kid and this passion has grown year by year. Now he is doing radio for a living.

“I started listening to the radio as a real young kid. In fact listening to the radio is what made me want to get into radio. I listened to that growing up and now I get paid to play music. I wanted to do it as a kid and that’s what I do now for a living. I’m actually a radio presenter here in the United States, play music on the radio, put together commercials, manage FB pages for radio stations and general stuff like that,” Paul said.

Paul started to listen to VOV in the summer of 2015 and since then VOV has become an indispensable part of his listening schedule.

Paul said he listens and sends in reception reports to VOV quite often with every detail he recorded with his radio equipment: “I like the music, especially when they play the older music. I also like to listen to news because I like the different perspectives, different opinion on it because other countries see things differently than we do and I like to hear that. I like the Letterbox program that is one of my favorites, I like to hear how other listeners tune into VOV and what they like about it and it seems like a fairly large amount of people like the music so I know there’re many of us out there. VOV’s English announcers are very friendly”[…]

Continue reading at the Voice of Vietnam online…

Travelling and DXing with the Bonito MegActive MA305 antenna

 

Ok, so officially it wasn’t a DXpedition; it was a well needed vacation in the sun after several hectic months of work, some of which involved travel to slightly more exotic locations. However, these days, I view any travel, whether it be for business or pleasure as a ‘DXpedition’ opportunity! Some of you might remember that I purchased a Bonito Boni Whip at the beginning of 2017 because (a) I needed another antenna and (b) a second Wellbrook loop felt like too much of an extravagance. They’re excellent antennas for sure, but at around £300, I couldn’t justify buying another. Thus, for about a third of the price I bought the Boni Whip. It proved to be an excellent choice – very compact and so perfect for my regular DXpeditions, quick to set up and capable of really excellent DX. There are many videos on the Oxford Shortwave Log YouTube channel that are testament to this. I wrote a couple of articles, published here on the SWLing Post which were seen by Dennis Walter of Bonito, who subsequently contacted me and offered to send over their MegActive MA305 E-field antenna for testing. Dennis made it crystal-clear that I was to ‘do my own thing’…test the antenna in any way I saw fit and publish my findings so DXers/radio enthusiasts could learn more about the capabilities of the antenna – from another DXer. I was happy to agree to this arrangement and the MegActive MA305 duly arrived, complete with two lengths of (bayonet BNC terminated) high quality H-155 coaxial cable.

 My portable Dxing kit with MA305 antenna                 The MA305 power inserter and USB power ‘brick’

The specifications of the MegActive MA305 are very similar to the Boni Whip; they both offer a Gain of +3 dBs, second and third order intercept points of greater than +30 and +50 dB respectively and both tune to 300 MHz. The MA305 is supplied with a longer radiating element and tunes down to 9 KHz (versus the 20 kHz lower limit for the Boni Whip). Obviously this isn’t a specification that is going to concern most radio enthusiasts; both offer fantastically wide operating bandwidths. The way in which these antennas do differ quite significantly however, is in how they are powered. The Boni Whip operates from 12 to 15 V, whilst the MA305 operates from 5 to 15 V. Bonito’s design philosophy regarding this feature is based on the increasing difficulty in procuring reasonably priced analogue external plug-in power supplies (they are no longer allowed to be produced due to power consumption restrictions).

Interestingly, when the power supply for my Wellbrook ALA1530 packed up, I called them to purchase a replacement and was told they only have limited stocks remaining. Thus, a solution for powering active antennas with a suitable low-noise supply is an issue that needs resolving. The guys at Bonito figured a USB power source was suitably quiet and with USB ‘power bricks’ almost ubiquitous these days for charging mobile phones and other portable electronic devices on-the-go, the idea could be applied to their active antennas. The result is the MegActive MA305, designed to operate at 5 Volts with no loss of performance. As a DXer who probably spends more time listening on DXpeditions than I do in my shack at home, the USB power solution was perfect. I myself often carry a cheap Chromebook laptop to use as an additional power source for my camera phone when I’m DXing, so Bonito’s design approach resonated with me completely.

 

Travelling with the MegActive MA305

Ok, so the MA305 is very compact and very light indeed – perfect for a trip to Crete! However, I know from many conversations with my YouTube friends and followers that some of us feel a slight sense of trepidation carrying shortwave radios and antenna systems on board flights, be they national or international. I myself wasn’t really concerned other than if my bag got pulled from the X-ray machine, there’s often quite a long wait whilst the security staff work through the queue of luggage requiring er…human intervention! Predictably, my rucksack did get pulled and I waited patiently until it was my turn to explain the contents! Looking back on this retrospectively, it’s hardly surprising. Other than the usual holiday paraphernalia, my rucksack contained:

  • A 10.0 metre length of H-155 coaxial cable
  • A 1.0 metre length of H-155 coaxial cable
  • Eton Satellit receiver
  • MA305 Coaxial Power Inserter
  • MA305 Antenna Amplifier
  • Bonito USB ‘Power Brick’
  • Bonito USB Power Cable
  • NooElec RTL-SDR dongle
  • NooElect ‘Ham It Up’ upconverter
  • Various screened cables and connectors
  • 10 metres of equipment wire

I explained to the (friendly) security chap that I was a shortwave radio hobbyist and identified the various pieces of equipment for him, as he removed them from my rucksack. He confirmed my X-ray had ‘lit up’ (in blue as it happens) with metallic/electronic items and was even kind enough to swivel his monitor to show me the mess of items strewn across the screen – just as I had thrown them all into my rucksack! However, after quickly swabbing some of the items, he said all was fine and hoped that I enjoyed my holiday and listening. Service with a smile at Gatwick Airport – and I was on my way. My outbound experience got me thinking whether it would be possible to pack my DXing kit in such a way that it wouldn’t alarm airport security. Thus, for the trip home, I packed all of my cables into my (checked-in) suitcase. I figured it would be obvious there was no security risk associated with cables alone. I then packed my RTL-SDR, upconverter and all of the MS305 components very neatly into a single box and put that in my carry-on rucksack. Now, some might argue that security measures at Heraklion International Airport in Crete differ a little from London Gatwick, but I observed staff at the X-ray machine very carefully monitoring every piece of luggage passing through it – including my own and I passed straight through without a problem. All I did was take my laptop out as usual, and put it in a separate tray. Job done.

DXing with the MegActive MA305

                                      My listening post in Crete, with the brilliant Eton Satellit receiver

My apartment in Crete was on the second floor and a large balcony provided a decent outdoor location for DXing. As regards electrical noise, the location was much quieter than my shack at home, but it certainly wasn’t perfect, thus a good test of the MA305 in a real-world pseudo-urban environment. in an attempt to improve SNR, I bought a cheap ‘Selfie Stick’ and some tape and managed to construct a mount for the amplifier, increasing the overall height above ground by about 1.5 metres and displacing the radiating element an additional 2 metres thereabouts from the building. I’m not sure whether it made much difference, but it seemed like the sensible thing to do for less than 10 Euros.

During my week-long stay, I managed to fit in several listening sessions and copied some really excellent DX from this ultra-compact, USB-powered set up. In fact, the MA305 coupled to the Eton Satellit performed so well, I managed to copy a number of personal firsts, including CRI on 7295 kHz, via their relay in Bamako, Mali, The Voice of Beibu Radio on 5050 kHz, Nanning, XSL ‘Slot Machine’ on 6251 kHz USB, Ichihara, Japan, S32 ‘The Squeaky Wheel’ on 3828 kHz and NHK World Radio Japan, 11910 kHz. I also copied RTM Wai/Limbang FM on 11665 kHz from Kajang, Myanmar Radio on 5985 kHz and AIR Bhopal on 4810 kHz, amongst others – all of which I would certainly consider to be difficult catches in Europe. To hear them with an 18 cm antenna felt pretty special. African shortwave stations were also very well represented and I managed to copy a number of them including Radio Hargeysa on 7120 kHz, Voice of Tigray Revolution on 59150 kHz, Radio Oromiya on 6030 kHz, Radio Fana on 6110 kHz, Radio Ethiopia on 7235 kHz, Radio Sonder Grense on 3320 kHz and Radio Guinée on 9650 kHz. I expected to hear all of these stations, except for Radio Guinée, which is farther away from Crete than the UK. So, all-in-all an excellent result.

Despite hearing a lot of excellent DX whilst in Crete, there is one signal I copied, which more than any other, demonstrates the DXing credentials of the MA305 – and Eton Satellit for that matter. In the early hours of the morning (00:59 hrs UTC) I copied and recorded Radio Tarma from Peru on 4775 kHz. With a TX power of 1 kW, this is a very difficult station to hear in Western Europe, even with a longwire. To catch this station in Crete, at all, was incredible on an ultra-compact set-up. It was at this point during the trip that I realised E-field antennas really do work superbly well for hard-core DXers on the move. It inspired me to conduct further tests back home in the Oxfordshire countryside, where electrical noise is absent. This I did a few days ago, with some quite amazing results on the Tropical Band. More on that to come in my next post. In the meantime, please find text links and embedded videos for selected reception recordings, below. Many more recordings are available on the Oxford Shortwave Log YouTube channel and please don’t hesitate to contact me if you require further information on the MA305 or the Eton Satellit. Thanks for reading/watching/listening and I wish you all excellent DX.


Personal firsts

Click here to view on Oxford Shortwave Log

 

Click here to view on Oxford Shortwave Log

 

Click here to view on Oxford Shortwave Log

 

Click here to view on Oxford Shortwave Log

 

Click here to view on Oxford Shortwave Log

 

Radio Tarma, Peru, 4775 kHz

Click here to view on Oxford Shortwave Log

 

Other notable catches

Click here to watch on Oxford Shortwave Log

Click here to watch on Oxford Shortwave Log

Click here to watch on Oxford Shortwave Log

Click here to watch on Oxford Shortwave Log

 

Clint Gouveia is the author of this post and a regular contributor to the SWLing Post. Clint actively publishes videos of his shortwave radio excursions on his YouTube channel: Oxford Shortwave Log. Clint is based in Oxfordshire, England.