Category Archives: Guest Posts

Jorge’s Portable YouLoop Antenna Frame

BricoDX: A YouLoop portable frame

by Jorge Garzón (EB7EFA · EA1036 SWL)

Youloop ‘in the forest’

One of the aerials I wanted to test was the Youssef Loop (YouLoop). I own a good passive loop antenna made by Tecsun (AN-200) but this is a mini one to use with portable receivers. A video showing the test of this ‘mini-loop’ can be seen in my YouTube channel.

My main loop for serious DXing is the Wellbrook 1530LN, but this is an active loop that easily beats any other passive ones. It’s close to be the perfect loop for me as I live in a rural valley with low noise level in the bands so I enjoy every minute of my listening sessions. However I wanted to test this newcomer passive loop, but wasn’t satisfied just hanging it from a pine tree branch, so I decided to bring about my DIY YouLoop portable frame project.

So I had to find something to get a rigid (but light) support for the loop itself allowing an easy rotation to achieve deep nulls. So… what could I built?

Fiberglass tubes, hooks and crossed arms.

I am professionally involved in the heritage and communication sector, so was easy for me to refit some dismissed display rolls where I found a 1,5 m thin supporting tube made in fiberglass that suited my needs. I cut a piece of 120 cm and then split it into 2x60cm, tightening both in the middle with a fine bolt. I placed two plastic hooks up and down of the vertical tube to hold both Youloop modules. The horizontal arm was lengthened with two bamboo meat skewers firmly inserted into the tube, allowing to slide onto it. Two small holes in the bamboo pieces were good enough to secure the cable with a short wire. All this was well fixed with clamps and vulcanized tape to an extra piece of vertical tube.

Bamboo meat skewer and tied cable.

Finally all this was inserted into a thicker aluminium tube and then into a wider one in order to fit everything into the tripod hole and then get a smooth and efficient rotation of the antenna. As a base I re-fitted an old heavy metallic tripod manufactured by Manfrotto (Italy) that I used it often for birdwatching day trips. I gave back an unexpected new life for this piece of metal, always in the field close to Nature!

The whole assembly can be easily transported in the car. Aluminium tubes slide one into the other, being rapidly detachable from the loop itself. This is a cheap and DIY project to get the maximum of this surprising and low noise passive loop.

This aerial gives its best performance when used in the field. There, QRM levels are low or non existent at all. It is a must to rotate it easily and then get sharp nulls. SMA connector nuts must be well tightened as they tend to loosen easily, but beware to force them as an extra twisting could damage inner connections.

This is the first post of a series called «BricoDX» where I will show how to refit or build accessories to get inexpensive and practical DIY projects for our listening sessions.

Many thanks for sharing your article with us, Jorge! That’s a brilliant loop support.

Readers: check out more of Jorge’s articles on his blog, @IberiaDX. Also check out his YouTube channel where he posts videos.

K9ZDK: Return of a Silent Key

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Many thanks to SWLing Post contributor, Dan Van Hoy (VR2HF), who writes:

It was one of the most sublime moments in my 55+ years in radio. Almost every night I listen to shortwave station, KNLS in Anchor Point, Alaska, from my home in Hong Kong. KNLS broadcasts to Asia and the Pacific in English, Russian and Mandarin. The English broadcast is an amazing mix of secular and Christian music and topics, science, current affairs and more. It has something for both the seeker and the saint and is one of the most informative and entertaining shows on radio.

On this particular Monday evening, August 3, 2020, I tuned in late to the English broadcast from KNLS at 1000 UTC, but went on to listen to the remainder of the show. To my complete surprise as the show closed I heard “73 de K9ZDK” in Morse code and quickly wrote down that callsign. I assumed it was the engineer on duty, obviously a ham, having a little on-air fun with a big transmitter and antenna.

A few minutes later, I also heard “CQ de K9ZDK” at the beginning of the Russian program at 1100 UTC. So, I looked up K9ZDK on QRZ.com and found it was Zavier, a young ham who had become a silent key in June of 2019.

Zavier Klingensmith (K9ZDK) Silent Key

A little more online sleuthing and a phone call later revealed that his father, Thomas, KL0K, was at the controls of KNLS that night sending Zavier’s final CQ and 73 on this planet with at least 1 million watts of power (ERP: 100KW TX + 10dBd TCI curtain array) all around Asia and the Pacific. His call on CW was heard on every English, Russian and Mandarin show that evening over 16 hours of broadcasts (two Continental 100 KW transmitters). Wow!

In Zavier’s memory, Thomas has created a DIY kit for an Iambic Keyer and is offering it for FREE (though you might want to send some $$ for his production and mailing costs…my suggestion) to anyone who asks. Details can be found at Thomas’, KL0K, QRZ page. Maybe one of the first things you can send when your keyer is completed is,”K9ZDK de YOUR CALL, 73 OM!”

Thomas, our thoughts and prayers go out to you and your family. Thanks for the amazing on-air tribute to Zavier. I suspect he was listening with a big, big smile!

Dan VR2HF, Hong Kong
(K7DAN, USA)

Guest Post: What is FM Lightning Scatter DX?

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Photo by Olivier Lance on Unsplash

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

What is Lightning Scatter DX?

by Bruce Atchison (VE6XTC)

Believe it or not, it’s possible to receive distant FM stations during a thunder storm. While lightning makes it difficult to hear AM and shortwave broadcasts, its crackles aren’t as evident on the 88 MHz to 108 MHz band.

When lightning strikes, it temporarily ionizes the air around it. Radio signals are reflected by the charged gasses and come back down to earth.

From my experience with this kind of DX, the signal became noticeably stronger during lightning strikes. This effect lasted for a second, then the signal level dropped to its former strength.

While a thunder storm raged overhead on July 7th, I used my CC Skywave SSB radio to check out the FM band. Instead of hearing E-skip as I had hoped, I found that tropo-like conditions reflected stations down to my home. I heard signals from a hundred miles away or further.

As just one example, I found a low-power station with the call letters CKSS on 88.1MHZ. They call themselves 88.1 The One. Find out more about this station at the http://www.881theone.ca/ link. It’s located in the town of Stony Plain, Alberta. This station plays country music and airs local news events.

At a guess, I’d say the transmitter is about 120 miles from my QTH in Radway. It normally doesn’t come in at all. The signal strength varied too, showing that it wasn’t a local.

In my instance of catching CKSS’s signal, a form of tropo ducting was also present. Rain can produce reflections of signals but it’s much more pronounced in the UHF and microwave bands.

When a thunder storm is ruining AM and shortwave reception, try DXing the FM band. You’ll be surprised at what occasionally comes in.

For further information on weather-related DX, check William R. Hepburn’s article.

To see a demonstration of lightning scatter on amateur TV, watch the
following video:

To hear what FM lightning scatter sounds like, watch this video:

Thank you for sharing this guest post Bruce. I’ll be the first to admit that I’ve never tried to hear lightening scatter DX, but I will certainly give it a go. This time of year, we’ve numerous thunderstorms in the afternoon and evening, so I’ll certainly have the opportunity!

Post readers: Have you ever caught FM DX off of Lightening Scatter? Please comment!

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

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!

W9IMS: A delayed start for the Indianapolis Motor Speedway special event station

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Many thanks to SWLing Post contributor, Brian D. Smith (W9IND), who shares the following announcement:

W9IMS: A delayed start for the Indianapolis Motor Speedway special event station

by Brian D. Smith, W9IND

It’s a late start for auto racing at the Indianapolis Motor Speedway, as well as the amateur radio station that honors this century-old tradition … but the show must go on!

And this week it will, as special event station W9IMS returns to the airwaves from now through Sunday to offer radio hobbyists a fresh opportunity to collect more “wallpaper”: Two vivid racing-themed QSL cards and the popular certificate known as the Checkered Flag Award.

The 2020 certificate will be easier than ever to earn. Normally the Speedway’s three major races take place on three different weekends, but this year, because of Covid-19 concerns, they’ll be consolidated into two. Accordingly, hams and SWLs will be required to contact or tune in W9IMS during only two race weeks – the current one, which continues through Sunday, July 5; and Aug. 17-23, which ends on the day of the venerable Indianapolis 500.

Even if you succeed in snaring W9IMS only once, you can still send off for the corresponding QSL card. All certificate and QSL designs are new each year.

The coming Independence Day weekend will feature an unprecedented racing doubleheader, with the IndyCar Grand Prix and the NASCAR Brickyard 400 slated for Saturday and Sunday, respectively. Consequently, the first W9IMS QSL of 2020 will be a full-color, four-sided card portraying images from both races.

So where do you find W9IMS? The station will stick to three bands, 20, 40 and 80 meters, and may appear at any time of day or night from now through Sunday.

However, the best bet is to catch the station during prime time – 2200 through 0200 UTC on weeknights (6 to 10 p.m. Indy time). W9IMS operators also plan to activate 20 meters during daytime hours, often between 8 a.m. and 2 p.m. (1200-1800 UTC); and will cover the various bands all weekend starting at 10 a.m. (1400 UTC) daily.

If you still haven’t caught W9IMS by the time Sunday evening arrives in Indianapolis, operators commonly conduct their own happy hour – working stations in rapid contesting style – right up to midnight (0400 UTC Monday).

Here are a couple of hints for tracking down the station during special event weeks:

Go to the W9IMS web page (www.w9ims.org), find the “2020 Operating Schedule” heading, and click on the link to “Grand Prix & Brickyard” or “Indianapolis 500.” Although some W9IMS operators get on the air at unscheduled times, you’ll have your best luck looking for the station during the hours and bands reserved with a name and a callsign.
Check DX Summit (www.dxsummit.fi) for spots that identify the current frequency (or frequencies) of W9IMS, if any. And if you type “W9IMS” in the search box, you can customize it to show reports for only that station.

For additional details, consult the W9IMS web page. Feel free to submit both of your 2020 QSL card and certificate requests in the same envelope, and if you don’t have your own QSL card, a printout of your W9IMS contacts or reception reports will suffice.

Building the EA3GCY DB4020 Dual-band 40 and 20M QRP SSB Transceiver Kit (Part 1)

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Many thanks to SWLing Post contributor, Frank (ON6UU), who shares the following guest post:

Building EA3GCY’s DB4020 QRP Transceiver kit

by Frank Lagaet (ON6UU)

In May, I discovered via a newsletter that a new kit was available from Javier EA3GCY in Spain. I was immediately sold as this was a kit from my favourite kit producer and it has 2 bands–it will also be able to do CW and there also will be a CW filter.

After building 2 MFT’s from Javier which work without problems, I needed to have the DB4020. The MFT’s are for 20 and 40 mtrs and do DSB (double side band). I did put them in a not-so-graceful box but they do what they are intended for which is QRP phone (SSB). They came together without problems so I expected the same for the DB4020–I knew for sure when I saw the board: all through-hole components (except for some capacitors which are factory soldered) and a lot of space on the board. The board has been silk-screened with clear indications on where all components have to come and the manual has very clear instructions where each component has to be soldered with referral to a quadrant. The manual provides a 252 quadrant page so it is a piece of cake to find where each piece goes.

What do you get?

Javier provides you with all components which need to be installed on the board and, of course, the kit board. The components come in small marked plastic bags and all is well-wrapped up in bubble wrap. The board is wrapped separately and that is put together with the component wrap which is then again wrapped up in bubble plastic. All goes into an envelope. Very well packed I must say.

Here’s a picture of the bags with components:

The silk-screened board:

I started with the resistors since that’s the easiest way. After that, I did the capacitors. I like to solder in all flat components first, so next were the diodes and IC sockets followed by the elco’s. The transistors were next together with all relays. As you solder in the transistors one also has to mount the cooling heatsinks, these cooling sinks are high and are ideal to protect the coils one has to make, they also protect the polystyrene caps (which I always find vulnerable) when the board is upside down.

Many kit builders are afraid of winding the toroids in kits–don’t be! It is easy. Just take your time and follow the instructions given by Javier in the construction manual. In this kit the builder has to wind 8 toroids: 6 are a single wire which goes through the toroid body, 1 is a toroid with 2 different windings, and 1 has a twisted pair which goes through the final toroid. Be sure to measure the wire you need per toroid as instructed in the manual. Javier gives some spare, so you can be sure. You will also see that on next picture where the legs of the toroids have not been trimmed yet. Once done I still had some centimetres of wire leftover.

Picture of the toroids ready to be soldered in:

Finally all other parts and pin headers went in, jumpers were immediately put on where needed.

As I’m using a military-grade plastic box, I have to break-out some components like the display, tuning encoder, volume and rx control from the board. I also have put an on/off switch on the box and already have the CW KEY connector ready installed. I also installed a loudspeaker in the box. The SI5351 board and the Ardiuno Nano are the final components which go into the board after installing all wires.

Picture of the board:

I intend to attach a CW paddle to the box made out of a relay. A HWEF tuner (from EA3GCY) which I was planning to incorporate in the box is I think a bit overkill. That HWEF tuner is already in a nice little box and would be a pity to dismantle, also I’m running out of space in the box… Maybe I can fit in a 9-1unun which would then give me good results on both bands…?

Maybe I will install a battery pack in the same box.

The box with board installed:

The box completed front side:

Mind you, it still needs some additional switches for the CW part of the transceiver.

73
Frank (ON6UU)

Video

Brilliant, Frank! I really appreciate the video as well–sounds like the kit produces smooth audio and should serve you well. No doubt, that military box enclosure will survive even the roughest field conditions!

Click here to check out the DB4020 kit at EA3GCY’s store.