Monthly Archives: May 2020

Radio technology magazines both online and in print

Many thanks to SWLing Post contributor, Mangosman, who writes:

There used to be magazines like Radio Electronics (USA), Practical Wireless (UK), Radio Television and Hobbies (Australia) and other magazines on electronics were sold in shops and on subscription for money which paid their writers. The internet has killed most of these magazines. There are still a few still in publication that I know of:

There are other Amateur radio magazines as part of membership.

Silicon Chip

Silicon Chip magazine publishes an extensive range of electronics projects every month including many which use Arduino, Raspberry Pi and Australia’s own very popular Micromite/Maximite microcontrollers. These projects are conceived, developed, constructed, written, photographed published and any unusual parts are sold on the magazine’s website by professional people who are paid by sales of the magazine.

Whether you’re into the latest digital electronics or prefer restoring vintage radios, or anywhere in between, we have something to interest you.

Of particular interest to radio enthusiasts are;

New W-I-d-e-b-a-n-d RTL-SDR Modules Part 1  and Part 2 where the performance of the available modules are measured and compared by Jim Rowe. Some modules will not work at all below 30 MHz but will above. Sensitivity dropped off at different frequencies depending on the module. Jim has the testing knowledge because he constructed his own version in 2013. Also check out Using the SiDRADIO to receive DRM30 and More Reception Modes for the SiDRADIO.

More recently they published a touch screen DAB+/FM/AM radio construction project.

The online subscription rate is  $Au 85 (= $US 56.29 = € 51.12 = £ 45.88) at the moment for a year of 12 magazines. Individual articles are also available. GST is an Australian Goods and Services Tax.

The above magazines produce their own content rather than just promote a manufacturers’ product.

Many thanks for the suggestions, Mangosman! I imagine there are a number of electronics magazines still in publication in other languages, too. Readers, please comment if you subscribe to a quality publication not mentioned above.

I would also note that if you would like to read archived/vintage copies of electronics and radio magazines–some dating back to the early 20th century–explore the American Radio History website.

Spread the radio love

Radio Waves: Hacking Satellites, “Close-Knit” Ham Radio Culture, TV Drama Diplomacy, and Ofcom Relaxes Restricted Service Licence

(Image: NASA)

Radio Waves:  Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers.  To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors BJ Leiderman, London Shortwave, and Michael Bird for the following tips:


Hacker Used £270 of TV Equipment to Eavesdrop on Sensitive Satellite Communications (CBRonline.com)

“Vulnerable systems administration pages and FTP servers were publicly routable from the open internet.

An Oxford University-based security researcher says he used £270 ($300) of home television equipment to capture terabytes of real-world satellite traffic — including sensitive data from “some of the world’s largest organisations.”

James Pavur, a Rhodes Scholar and DPhil student at Oxford, will detail the attack in a session at the Black Hat security conference in early August.

Pavur will also demonstrate that, “under the right conditions” attackers can hijack active sessions via satellite link, a session overview reveals.

The news comes as the number of satellites in orbit is expected to increase from approximately 2,000 today to more than 15,000 by 2030. (Elon Musk’s SpaceX alone has permission to launch 12,000 satellites.)[]

A close-knit culture, with separation at its core (Christian Science Monitor)

Ham radio operators are a global collective with a common aim: to forge human connections in an expanding network. As COVID-19 makes us all ‘distance,’ we wanted to tune in to their world.

You’re logged in, the Zoom meeting underway, and suddenly faces freeze. The best you can do: Reboot the router and cross your fingers. You’re on the phone with a friend, deep in conversation, and the audio gets garbled as the bars on your phone drop from one to none. Technology can fail us at inconvenient times. But imagine a communications technology that could hold up even in the most rugged and remote situations.

It exists, and it’s much older than the smartphone.

Amateur radio, or ham radio, has been around for more than a century, functioning as both workhorse and recreational hobby. After the Boston Marathon bombing in 2013, amateur operators coordinated communications as cellphone systems became overloaded. They played a key role in Puerto Rico in 2017 after Hurricane Maria took down much of the communications infrastructure. Though there hasn’t been as much of a need during the pandemic – with traditional systems up and running – amateur radio is keeping its own user communities in touch, informed, and emotionally grounded.[]

Australia criticised for TV drama diplomacy (Radio New Zealand)

[Listen to full interview above or at RNZ.]

Australia has been told it should not send low-brow TV dramas and reality shows to the Pacific, but find out what the region really wants.

Canberra has announced plans to stream television content to the Pacific as part of efforts to promote Australia’s relationship with the region, and to counter Chinese influence.

But a spokesperson for advocacy group, Australia Asia Pacific Media Initiative, Sue Ahearn, says sending programmes like Neighbours, Border Force is not the answer.

She believes Australia could provide a much greater service for the Pacific.[]

Update: Licensing drive-in movies and church services (Southgate ARC)

Drive-in movie and church service event organisers could be granted temporary radio licences by Ofcom, which may allow film lovers and congregations to come together while still observing social distancing.

Ofcom has today updated its licensing information to offer guidance to individuals or organisations who may wish to hold these types of events. They require a ‘restricted service licence’ from Ofcom, so that people in their cars can hear the film soundtrack, or what is being said, on their FM car radios.

Given the current coronavirus pandemic, we are waiving the usual 60-day notice period for licence applications. We will also process applications quickly, with the aim of providing an answer to applicants within two weeks of it being received.

We recognise that these events may be a way for communities and congregations to enjoy a film or to worship, while still observing social distancing. In granting any licence, however, we are not authorising the event itself. It is for licensees to ensure that any events are permissible under Covid-19-related laws and guidance.

More information, including on how to apply for a restricted service licence, is available.
Licensing information []


Do you enjoy the SWLing Post?

Please consider supporting us via Patreon or our Coffee Fund!

Your support makes articles like this one possible. Thank you!

Spread the radio love

New Raspberry Pi 4 Model B with 8GB of RAM

When the Raspberry Pi 4 Model B was introduced last year, I immediately purchased two of the 4GB models for my daughters. A the time, 4GB was the maximum amount of RAM available.

Both of my daughters have been using their Pi 4’s with a Raspian distribution to learn Python, Linux Command Line and, of course, to cruise the web. They each had a Rasbperry Pi 3B prior to this and found that–especially if loading videos or media-rich web pages–it would often crash the browser. The Pi 4’s, however, have been much more stable.

The Raspberry Pi Foundation launched the 8GB version this morning. The price is $75 US for the board only.

Click here to read the full announcement and click here to find a distributor.

Spread the radio love

The Yaesu FT-70G: Where the FT line met Milcom

Earlier today, I stumbled upon a very unique transceiver in Universal Radio archives: the Yaesu FT-70G.

Here’s the description from Universal:

The Yaesu FT-70G is a portable HF transceiver covering 2 to 30 MHz transmit. Receive is from 500 kHz to 30 MHz. Frequency selection is via BCD switches to 100 Hz. There is a clarifier for fine tuning. Optional FNB-70 NiCad Battery. Please note that the optional 10F-2.4DL filter is required for LSB opeation.

The Yaesu FT-70F is similar, but is a channelized fixed version offering up to 11 frequencies.

Two hours ago, I was not aware that the FT-70G existed.  Now? I want one!

I’m a real sucker for vintage rugged field radio gear, so I never discovered the FT-70G until today. Turns out, they’re relatively rare. A little light research reveals that it’s a highly-desired transceiver in the world of HF Packers–those radio enthusiast who like “manpack” commercial and military gear.

The FT-70G has a distinct military look and feel with the BCD switches to change frequency, rugged toggle switches, chassis extensions to protect the front panel, and attached screw-on connector caps.

What’s really surprising is that the FT-70G has a general coverage receiver (500 kHz to 30 MHz). Admittedly, it would not be fun band-scanning with those BCD switches…but still!

This website has a number of photos. They also have a product description likely from the original Yaesu/Vertex Standard FT-70G description:

“The FT-70 series HF field portable manpack transceivers are designed to provide reliable communications under rugged conditions in the military and commercial environment. The frequency synthesized, all solid-state circuitry and die-cast anodized aluminum enclosure and battery pack make a highly portable, weatherproof station. Flexible operation for optimum communications under a wide range of propagation conditions are assured by SSB (USB, LSB), semi break-in CW, AM, or audio interfaced Data modes. All controls, antenna, and interface ports are available and selectable via the front panel for maximum effectiveness and ergonomics in field, base, and manpack applications. The companion antenna tuner FC-70 is compatible with walking manpack, field portable, or base configurations. The highly effective vertical tripod mount antenna system YA-70 is deployed and stowed easily and quickly, pulling double duty by converting to manpack whip while on manuevers. High quality handset YH-70 provides communications privacy and clarity.”

Again, check out the excellent photos of the full manpack kit.

As I researched pricing, I discovered this FT-70R with accompanying FC-70M antenna tuner on eBay right now with only 6 hours left of bidding:

At time of posting, the bids are at $520. I fear this will soar well above my comfort level before bidding ends. (Like I need another field radio anyway, right?)

Post readers: Please comment if you’re familiar with the FT-70G and especially if you’ve ever owned one.  I’d love to hear about your experience with this unique rig.

Spread the radio love

Guest Post: Tom takes the AirSpy HF+ and YouLoop to the field!

Many thanks to SWLing Post contributor, TomL, who shares the following guest post:


YouLoop Picnic Table Report

by TomL

So, I finally got around to testing my Airspy YouLoop after the long shipping delay from China.  It is simple in concept and will not repeat what others have written about it in previous articles.  I find it a useful loop antenna for portable operations and sometimes for noisy home use.  This report is focused on my usual field location from a Northern Illinois county park picnic table.

Setup

As you can see from the setup photo, it all fits into a backpack except for the two PVC pipes and crossbar which are easy carried.  I modified my YouLoop to use the 2 meter transmission line as one half of the loop.  The other half consists of the two shorter wires connected with a simple female-to-female SMA connector.  This doubles the circumference of the loop and gives it a bigger capture area.

Crossbar

Because my setup is bigger than usual, I had to find a lightweight cross member to aid the solid conductor wire from sagging. I found just the thing in a larger-than-normal 6 foot fiberglass driveway snow marking stick sold at the local hardware store.  I cut the tip off to make it 5 feet (Because, the loop as I configured it is 4 meters circumference, so, 4*39.37/Pi = Diameter in inches). I then drilled a 5/16th’s inch hole through the middle of the ¾ inch PVC threaded pipe I had from a previous project and fit the fiberglass stick through it as the crossbar. This is a special PVC 4 foot nipple pipe I had special ordered a long time ago when mounting a previous (heavy) Ferrite-Sleeve loop antenna.

Loop Mounting

Screwed onto both ends of the 4 foot nipple are threaded-to-coupler adapters also found at the hardware store.  The adapter allows me to attach easily to the ¾ inch 5 foot long PVC pipe held by my trusty carbon fiber tripod below.  This 5 foot pipe is held loosely by the tripod so I can grab the pipe and turn the whole loop mounted above.  The result is not perfectly circular and there is room for improvement.  I find it to be highly directional nonetheless and easy to turn. The phasing connector of the YouLoop mounts at the top and for now I am just using two medium sized cable ties to a long screw near the top for tension.  I do not want to glue the connector to the top since this YouLoop may get used in other configurations in the future.

The Bottom connector for the radio input is held nicely with a couple of velcro wraps.

The wire from there goes to the usual setup of Palstar amplified preselector with battery pack and Airspy HF+, which goes into the USB port on the small Dell laptop.  After some initial problems with a non-functioning HF+ and rebooting a few times, I was finally able to get a signal.  At first I thought it was the antenna but the error condition acted the same way whether the antenna was connected or not.  It could be that my HF+ is starting to exhibit the first signs of failure, which I have read about from complaints on the internet about the reliability of SDR’s used in the field.  I may have to bring along my SDRPlay SDR2 just in case!  In other words, don’t depend on computer hardware and software to work (especially if you happen to go on vacation and have no backup radio!!).  I also have a couple of portable non-SDR radios I could bring with me as well.  Enough said.

Using It

The screen of the laptop shows a very nice black background, very quiet, and a moderate signal level of WRMI on the 31 meter band.  I did not have the time or processing power for real Data captures, so all I have to share are less optimal MP3 files.  The signal level is somewhat low. I think this is typical for a single-wire loop antenna and seems adequate. I did have to crank my Palstar preamp to maximum the whole time while on shortwave (my Wellbrook amp would probably work slightly better).  On mediumwave, the gain seemed more than adequate (I don’t have any recordings of that band at this time, maybe a future article).

Directionality is very good and usable across a very wide range of frequencies!  It certainly worked well up to the 25 meter band where I started to notice a drop off of nulling ability.  And this is good despite my lack of perfect circular mounting of the wire. Even though my county park is a “Forest Preserve” and not meant to have any development, there is increasing noise in the neighborhood and I find the loop to be very useful in cleaning up some background noise (as well as noise coming from the laptop!).  This is especially seen with the Voice of Iran broadcast in French. The weak signal was aided by moving the loop to balance the signal level to local noise.

The loop is a bit flimsy using it this large.  Keeping the connectors tight may be a problem in the future if subject to a lot of wind.  I think you will find the smaller (usual) setup in the instructions to be less of a problem.  My plastic clips at the sides of the crossbar and the plastic tie downs at the top are not optimal and will need something better (in other words, it would help if I had a better mounting for the wires).  Also, the tripod definitely wanted to tip over as a storm blew past, so I need to make sure I tie down one or more legs to the picnic table in the future!!

Final Thoughts

In summary, this is a very useful loop for portable operations since it fits easily into a backpack. Mounting it in a repeatable manner will need some experimentation.  Performance is good with usable nulling at a wide range of frequencies. Signal strength is moderate, so a good preamp is necessary in order to boost the signal into the sweet spot of your receiver RF stage.  Parts quality is good, but the wire is thin solid conductor, so do not kink/fold it!.  The connectors and housing for the phase change and balun are very small, with non-waterproof plastic housings that can be easily abused, so take care of them. The whole kit is small to pack and lends itself to experimentation.  Highly recommended given its limitations.

Furthermore, I feel my old, original 14-inch “crossed-parallel loop” did as good a job as this larger diameter YouLoop.  I wonder how the YouLoop can be modified to create a larger gain using, say, two or more wires in parallel (perhaps a future article!)?  Generally, the deeper the loop design, the higher the gain.  The YouLoop potentially could be a better performing, more portable version if I can replicate using more turns of wire.  Although it is in disrepair now, pictures of my old 14-inch loop are found here, and also here.

Sample Recordings

Here are a bunch of sample recordings to enjoy, some of which are unique to shortwave radio and found no where else:

9830 kHz, Voice of Turkey

10000 kHz, WWV

9395 kHz, WRMI

9420 kHz, Voice of Greece

11760 kHz, Radio Habana Cuba

11780 kHz, Radio Nacional Brazilia

11940 kHz, Radio Nationale Espana

7193 kHz, W3M – special Amateur Radio event to celebrate the birthplace of Memorial Day (Boalsburg, Pennsylvania) 

7230 kHz, Voice of Iran (French)

7315 kHz, Voice of Vietnam, from WHRI-1 transmitter

7350 kHz, Radio China International, in English from Kashi PRC

7375 kHz, Radio Romania booming in from Romania

7490 kHz, WBCQ (Spanish) from Monticello ME (guide says only 50 kw but sounded more than that)

6180 kHz, Radio Nacional Brazilia

6070 kHz, CFRX Toronto – discussion about some people with ashes of relatives in the home

6115 kHz, WWCR Nashville TN – discussion about Jesus saving a young woman from Satanic ritual abuse as a child

5850 kHz, Radio Slovakia International from WRMI booming in as usual

73’s & Happy Listening,

TomL


Thank you, Tom, for sharing your field-portable SDR setup! I like how you’ve made an inexpensive and packable support system for the larger diameter YouLoop. While I’ve yet to design a similar system around the YouLoop, I really should. I’ve always believed that for both SWL and ham radio field-portable operations, a self-supporting antenna system is a must as it gives you ultimate flexibility to cope with variable site conditions.

Click here to check out Tom’s previous guest posts and portable adventures!

Spread the radio love

FTIOM & UBMP May 31-June 6; Second Test of 7440 May 29

From the Isle of Music, May 31-June 6:
This week, we enjoy a Cuban dance party with four new releases from the Bis Music label. Special guest Ricardo Oropesa will be with us for part of the program.
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 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 uplinks from various websdrs in Europe.
The Facebook page for the program is https://www.facebook.com/fromtheisleofmusic/
The Patreon page for the program is https://www.patreon.com/tilford

Uncle Bill’s Melting Pot, May 31 and June 2:
In the first half of episode 167, Egyptian orchestral and Iraqi oud music. In the second half, our monthly Radio Balcony segment has special guests and new music including Jesse Charbonnier from the USA, César Rodríguez from Colombia, Ramiro Pinheiro from Spain and Nic Bennett from the UK.
The transmissions take place:
1.Sundays 2200-2300 (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 2000-2100 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 including a live uplink from a listening radio in the Netherlands at http://websdr.ewi.utwente.nl:8901/?tune=6070am
The Facebook page for the program is https://www.facebook.com/UncleBillsMeltingPot/
The Patreon page for the program is https://www.patreon.com/tilford

A second test broadcast of both programs will take place on 7440 kHz from Germany to rule out a bad day during the first test on Friday, May 29 from 1600-1800 UTC.

Spread the radio love

Soviet era Kerosene Lamp Generator gives new meaning to “Let’s fire up the radio!”

Many thanks to SWLing Post contributor, David Day, who recently shares the newspaper clipping above.

I was not aware of this Cold War era kerosene lamp generator, but it’s an ingenious use of the thermoelectric effect for power generation. I found yet another another clipping online:

Devices that work off of thermoelectric effect have been around many decades.

The original BioLite stove burns twigs/sticks to recharge USB devices with 3 watts of power.

I’ve often thought about purchasing a BioLite camp stove–the same one Anil Raj mentioned in our Radio Challenge II–as a companion to charge devices while camping off-grid.

BioLite now makes a more efficient (albeit pricier) stove that produces more power with less fuel.

At the end of the day, I find it so easy to use solar power to recharge larger LiFePo batteries, I’ve never invested in the BioLite.

With one large LiFePo battery, I’m able to power multiple devices including an inverter if necessary.

I’m very curious how many models of kerosene lamp generators were made back in the day and how useful they were for powering other low-drain devices.

Please comment if you’ve ever used a kerosene generator. We have readers from across the globe, so I imagine someone may have at least seen one of these in person and potentially used it to power a radio!

Oh, and obviously I need to think up another SWLing Post Radio Challenge–it’s been ages since our last! 

Spread the radio love