List of electronics and radio surplus outlets

Many thanks to SWLing Post contributor, Neil Goldstein, who writes:

I added a sub-page to radiokitguide.com with a list of the remaining electronics and radio surplus outlets I was able to find and verify. The list is evolving, but is complete enough to publish at this point. Enjoy!

https://fofio.blogspot.com/2020/07/sources-parts--outlets-and-more.html

Many thanks for sharing, Neil!

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Videos: RTL-SDR/YouLoop combo and exploring SDRs

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

I recently made another video on the AirSpy YouLoop – this time paired in a configuration that shouldn’t really work. I used it with an RTL-SDR v3 dongle in direct sampling mode, and signals still came in. This was somewhat of a surprise given the RTL-SDR v3 isn’t primarily designed for HF.

It may be interesting to readers of the SWLing blog.

I have also started a 2020 SDR Guide that may also have some relevance. Episode 1 looked at some of the things that are possible using Software Defined Radios, and Episode 2 which was released yesterday was an introduction to accessing over 500 online SDRs through 4 different platforms. I focused mainly on HF, and although I didn’t specifically mention the broadcast bands, gace a demo of each platform (KiwiSDR, WebSDR, SpyServer & SDR Console).

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Special VORW Radio International Broadcasts This Weekend!

Hello readers! I’m pleased to announce that I’ll be doing a special broadcast of VORW Radio International on Saturday the 18th of July and Sunday the 19th of July. This is purely being done for the fun of it and no other reason.

The show will feature good music, listener requests, comments and responses to listener emails. There will be a 1 Hour show on Saturday and a 2 Hour show on Sunday. The broadcasts will be transmitted live for listeners in Europe from Moosbrunn, Austria and repeated for listeners in North America from WRMI in Florida.

Here is the broadcast schedule:

(LIVE) Saturday 1700 UTC (1 PM Eastern / 7 PM CEST) – 6070 kHz – Moosbrunn 300 kW – Europe, The Middle East & Africa

Saturday 2200 UTC (6 PM Eastern / Midnight CEST) – 9395 kHz – WRMI 100 kW – North America

(LIVE) Sunday 1300 UTC – 1500 UTC ( 9 AM Eastern – 11 AM Eastern / 3 PM CEST – 5 PM CEST) – 6070 kHz – Moosbrunn 100 kW – Europe 

Sunday 2100 UTC (5 PM Eastern / 11 PM CEST) – 7780 kHz – WRMI 100 kW – Eastern North America

Monday 0200 UTC (10 PM Eastern / 4 AM CEST) – 5850 kHz – WRMI 100 kW – North America

A QSL will be given to any and all listeners who submit reception reports. Feedback is most welcome at [email protected]

I hope you can tune in!

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What are your Sunday radio plans?

Icom IC-756 Pro Transceiver Dial

I had planned on today being a rather laid-back Sunday with a good book lined-up and lots of radio time. Instead, my wife has convinced me to work on a home project this afternoon. That’s okay, because it is a project I’d like to get out of the way and the weather today is ideal.

Still, this morning, I’ve been hunting a few Parks On The Air (POTA) stations with the ‘756 Pro to help park activators along with their numbers. I try to do this when I can because I’m typically the activator and I truly appreciate logging well over my ten required stations for a valid field activation.

After the project this afternoon, I also plan to hit the 31 meter band and lower, catching a few broadcast stations and soaking in the shortwaves most likely with my RSPdx and HF+ Discovery SDRs.

It won’t be all SDR, though! I’ll be busy doing band-scans with my beloved Yaesu FRG-7 (Frog 7) while my SDRs record audio and spectrum.

Post readers: What are your plans today and this week?  Please comment!


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Adding CW mode to the EA3GCY DB4020 Dual-band 40 and 20M QRP Transceiver Kit (Part 2)

Many thanks to SWLing Post contributor, Frank (ON6UU), who shares the following guest post which expands upon his previous DB4020 article:


The EA3GCY DB4020 transceiver now has CW mode

by Frank Lagaet (ON6UU)

After telling you all about the DB4020 SSB build I’m here with the CW part of the kit,  let’s say this is part 2.  At a certain moment Javier let me know the CW interface kit was ready for shipment and some week later it was delivered to my QTH.

Again, a well packed kit arrived in a brown envelope, components and boards well packed in bubblewrap.  I found even a board I did not expect which can hold a push button,  a switch and the connector for your morse key.  Javier thinks of everything it seems!

Unpacking the bubblewrap gave me this result,  all components in 2 bags.  In the bigger bag another 2 bags with 2 printboards,  one for the CW interface,  one for the CW filter.  Great !!  Checking the material bill resulted in all components there,  another thumbs up.

I started, of course, immediately building it because I wanted CW in the transceiver as soon as possible.  I don’t do much in SSB mode anymore and I already started missing CW on the DB4020,  so I started my KX3 to listen to while I was populating the boards.  I never thought CW was going to have this impact on me! …. ..

I started building the CW interface,  again starting with all small items.  I soon saw that the 2 relays which need to be soldered in were ideal to protect all components when the board is upside down, so I soldered them in very quickly.  I then soldered in all other components ending with the elco’s.

Next phase was the CW filter.  This board is small and came together in a blink of an eye, no problems there, the long legs of the 3 and 4 pin headers went in last.

The following day, I made all wire connections and soldered a 13pin connector,  leaving one pin out since I want to have the option to choose the width of the CW signal I’m listening to.  By cutting the FL CW + pin and adding an additional switch, I have now 500Hz or 2400Hz.  Great option, for very little effort and simple.  Another thumbs up here.

Now it was simply a matter of inserting the sub boards in the main board and all should be working.  And it did!  Hurray!  The 500Hz filter works perfectly,  filtering away all above or below stations nearby my operating frequency.

This is the result of the soldering work,  2 small boards which need to be inserted in the main board:

The CW interface still needs the 13pin header of which I cut one pin and mounted a switch to have the 2400Hz width.

The IC you see in the middle of the CW interface is the KB2 keyer which gives you several functions like 4 memories and beacon mode.  The 4 potmeters are used to set the level on 40 and 20 meters,  to set the delay between TX and RX switchover and to set side tone monitor level.   The keyer also provides functions as keyer mode A or B,  straight key function and can be set for speeds between 1 and 50WPM.   WPM speed can be set in 2 different ways.  Handy!

Here a picture of the CW filter inserted on the main DB4020 board.

The CW interface is inserted at the side of the main board,  notice the 2 wires which go to the switch to allow switch-over between 500 and 2400Hz.

(Wiring still needs to be cleaned up in this picture.)

Finally, the result:  a good working multimode QRP transceiver with 2 bands.  It should be possible to make close to medium range with it as well as DX,  even with QRP power.

And while I was building I also made a new key for this radio,  it is made out of a relay and cost nearly nothing,  looks good doesn’t it ?  hihi.

Homebrew key

The key, when in practiced hands (fingers hi), can do 50 WPM without a problem. My friend HA3HK does without blinking an eye at 40WPM with this kind of key and tells me that he can go faster if needed.  Me? I’m going it a bit slower.

Battery pack

As this radio is only using little power (0.4A in RX,  1 to 2A in TX depending the power you set it) I thought,  let’s make a battery pack for the radio.

The first plan was installing it in the box.  I did not do that because the batterypack is also powerful enough to feed my KX2 and other QRP transceivers. Since I can use it with all of them, a loose battery works out better for me.

I started with an old laptop which had a broken screen and some other malfunctions,  but still had a good battery,  although I needed the battery connector of course.  A piece of wood to mount the connector on was my next goal.  And since I still have another laptop using the same batteries, I can charge the battery without problems.  Simple, but good and it weighs much less than a gel cell battery.

The battery provides me with 12.5V and some 5Ah.  Enough to last for hours on RX and for sure good enough to activate 2 SOTA sites in one day.   It doesn’t look great but works great– that is what matters and to test it was more then good.  Next will be getting the battery pack in a nice box.  Better to re-use stuff than throwing it away I’m thinking.

I need to do something about the cover of the OLED display,  there is still some work there to make it look nicer.

Some video can be seen on YouTube :

Finallym I’d like to thank you all for reading my articles about the DB4020. I had big fun soldering, tinkering with the box, making the key, and batteryholder/batterypack.  My Hungarian friend HA3HK told me it looks a bit like a spy radio. …. ..

I also include one more time the link where you’ll find this kit :

https://www.qrphamradiokits.com/

73 TU ee

Frank

ON6UU


Thank you so much, Frank. No doubt, you had a lot of fun putting this excellent little kit together.

Implementing a filter switch was a fantastic idea and, obviously, not terribly difficult to do.

Based on the videos, the DB4020 has a low noise floor and very good receiver characteristics. I’m impressed that the CW portion of the radios has so many features as well, such as a memory keyer and beacon mode.

I also love how you reused that 5Ah laptop battery! I think that could almost give you a full day of SOTA activations at those consumption levels!

Thanks again for sharing this with us, Frank! We look forward to your future articles!

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Radio Waves: Maritime Mobile Net Assists, Voice of Ambiguity, Promising Solar Cycle 25 Prediction, and the Future of Ham Radio

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 Rich Smith, Kim Elliott, and Pete Eaton for the following tips:


Maritime Mobile Service Network Comes to the Aid of Vessel in Distress (ARRL News)

The Maritime Mobile Service Net (MMSN) on 14.300 MHz came to the assistance of a sailing vessel on June 25. MMSN control operator Steven Carpenter, K9UA, took a call on 20 meters from Ian Cummings, KB4SG, the skipper of the Mystic Lady, then some 40 miles east of Florida. Cummings reported that his engine had failed as he was attempting to return to his home port of Stuart, Florida. He not only had insufficient wind, but a strong current was carrying the vessel out to sea.

Cummings had been unable to reach any station via his VHF marine radio, since he was too far from the coast. Assisting in the call was Robert Wynhoff, K5HUT, also an MMSN net control operator. Cummings said his vessel, with one passenger on board, was drifting northwest toward the South Carolina coast.

“A major concern was that the vessel was heading directly towards a lee shore,” the MMSN reported. “Lee shores are shallow, dangerous areas which are a hazard to watercraft. Vessels could be pushed into the shallow area by the wind, possibly running aground and breaking up.”

Carpenter contacted Cummings’ family, who had already called the Sea Tow marine towing service. Sea Tow advised Carpenter to tell the captain to head closer to shore by sailing west, if possible. Carpenter told Cummings that if he was unable to get nearer to shore, he would notify the US Coast Guard, which was already monitoring the situation.

As the MMSN reported, “The Mystic Lady was able to make some headway, but it was very slow. Members of the MMSN made additional calls via landline to the captain’s family as to the ongoing status of those on board. The family was concerned but relieved that communication was established and that all were well.”

Several hours later, the captain advised that the wind had picked up, allowing him to head close enough to shore for Sea Tow to reach the vessel and take it back to port.

The Pacific Seafarers’ Net, which monitors 14.300 MHz from the West Coast after the MMSN secures at 0200 UTC, kept in touch with the Mystic Lady into the night while it was under tow.

The tired, grateful captain later messaged the net, “A million thanks to everyone last night who helped rescue us on 14.300. Everyone chipped in as we drifted north in the Gulf Stream 60 miles headed to a lee shore. The MMSN net control and several others stayed with us for hours, phoned people, and were immensely helpful. The situation on board was dangerous. We are now safely under tow home. You folks are amazing!”

In operation since 1968, the MMSN monitors 14.300 MHz 70 hours a week to assist vessels and others in need of assistance. — Thanks to MMSN Net Manager Jeff Savasta, KB4JKL[]

VOA: Voice of ambiguity (The Hill)

From 1985 to 2017, I was an audience research analyst at the Voice of America. During that time I was preoccupied by the fact that the BBC World Service had a larger audience than VOA. VOA had a larger budget, so money was not the issue.

In audience surveys, I inserted a question asking those who listened to BBC more often than VOA: “why?” The answer provided most often was trustworthiness of the news.

I asked a listener from Burma (now known as Myanmar) why he thought BBC is considered more trustworthy than VOA. He replied that VOA is more closely connected to the U.S. government than BBC is to the U.K. government. I asked how he knows this. He responded that it’s because VOA says so every day.

He was referring to the “disclaimer” at the beginning of the editorials that, by the 1980s, were heard daily on VOA’s English broadcasts: “Next, an editorial reflecting the views of the United States government.”

The daily editorial was a requirement handed down by VOA’s parent U.S. Information Agency. The editorials are drafted by the VOA’s policy staff, sent to the State Department for approval and finally broadcast after a sometimes lengthy back and forth.

Michael Pack, the new CEO of the U.S. Agency for Global Media, VOA’s present parent agency, is restoring the editorials to their previous prominence on VOA. In recent years, with diminished radio output, editorials were relegated to VOA’s little-viewed satellite television service and to a website separate from the main voanews.com. The revival of the editorials is a step in the repoliticization of VOA.[]

Newer Solar Cycle 25 Forecast Runs Counter to Consensus (ARRL Newsletter)

Scientists associated with the National Center for Atmospheric Research, the University of Maryland, NASA Goddard Space Flight Center, and other institutions are offering a “bold prediction” on how Solar Cycle 25 will play out. In a paper, “Overlapping Magnetic Activity Cycles and the Sunspot Number: Forecasting Sunspot Cycle 25 Amplitude,” they assert that the next sunspot cycle will be of major proportions. The forecast stands in stark contrast to the consensus of forecasters who predict that the magnitude of the nascent Cycle 25 may not be much different from the current unremarkable solar cycle, which appears to have reach its low point.

“From the dawn of modern observational astronomy, sunspots have presented a challenge to understanding — their quasi-periodic variation in number, first noted 160 years ago, stimulates community-wide interest to this day,” the abstract points out. “A large number of techniques are able to explain the temporal landmarks, (geometric) shape, and amplitude of sunspot ‘cycles,’ however, forecasting these features accurately in advance remains elusive.”

Monthly sunspot numbers since 1749. The data values are represented by dots, and the 12-month running average values are illustrated as a red shaded area. Vertical blue dashed lines signify the magnetic activity cycle termination times that trigger the rapid growth of sunspot activity.

The paper notes that recent studies have illustrated a relationship between the sun’s 22-year Hale magnetic cycle and the production of sunspot cycle landmarks and patterns, but not the amplitude of the cycle.

“Using discrete Hilbert transforms on 270 years of monthly sunspot numbers to robustly identify the so-called ‘termination’ events — landmarks marking the start and end of sunspot and magnetic activity cycles — we extract a relationship between the temporal spacing of terminators and the magnitude of sunspot cycles,” the abstract explains. “Given this relationship and our prediction of a terminator event in 2020, we deduce that Sunspot Cycle 25 will have a magnitude that rivals the top few since records began. This outcome would be in stark contrast to the community consensus estimate of Sunspot Cycle 25 magnitude.”[]

The Uncertain Future of Ham Radio (IEEE Spectrum)

Software-defined radio and cheap hardware are shaking up a hobby long associated with engineering

Will the amateur airwaves fall silent? Since the dawn of radio, amateur operators—hams—have transmitted on tenaciously guarded slices of spectrum. Electronic engineering has benefited tremendously from their activity, from the level of the individual engineer to the entire field. But the rise of the Internet in the 1990s, with its ability to easily connect billions of people, captured the attention of many potential hams. Now, with time taking its toll on the ranks of operators, new technologies offer opportunities to revitalize amateur radio, even if in a form that previous generations might not recognize.

The number of U.S. amateur licenses has held at an anemic 1 percent annual growth for the past few years, with about 7,000 new licensees added every year for a total of 755,430 in 2018. The U.S. Federal Communications Commission doesn’t track demographic data of operators, but anecdotally, white men in their 60s and 70s make up much of the population. As these baby boomers age out, the fear is that there are too few young people to sustain the hobby.

“It’s the $60,000 question: How do we get the kids involved?” says Howard Michel, former CEO of the American Radio Relay League (ARRL). (Since speaking with IEEE Spectrum, Michel has left the ARRL. A permanent replacement has not yet been appointed.)

This question of how to attract younger operators also reveals deep divides in the ham community about the future of amateur radio. Like any large population, ham enthusiasts are no monolith; their opinions and outlooks on the decades to come vary widely. And emerging digital technologies are exacerbating these divides: Some hams see them as the future of amateur radio, while others grouse that they are eviscerating some of the best things about it.[]


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A new visitor in the shack: The HobbyPCB IQ32 SDR QRP transceiver

Last week, I took delivery of an IQ32 SDR Transciever on loan from HobbyPCB. The IQ32 has been on the market for a few years now and is a fusion of the HobbyPCB RS-HFIQ and the STM32-SDR.

I’ve been told by the HobbyPCB team that the STM32-SDR was developed a few years ago “when PSK31 was the digital mode du jour and PS2 keyboard roamed the land.” Cool thing is, the team is still updating the radio’s firmware.  Most recently, they expanded the rig’s CW capabilities and re-worked the memory structure and organization based on user feedback.

I see the IQ32 as a collaborative transceiver project and look forward to trying a few QRP PSK-31 contacts in the field with only the transceiver, antenna and a PS2 keyboard. Need to check the shed for that keyboard!

Anyway, should be fun!

I plan to write an article for The Spectrum Monitor about the IQ32, explore how it came about, and point out some of its unique features. It’ll be less a review and more of a tour of this little rig.

For more IQ32 info and specs, visit HobbyPCB online.

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