Category Archives: Guest Posts

Bridging Two Worlds: Shortwave Listening Meets Amateur Radio

When the SWL and Amateur Radio hobbies meet

Many of us who are also amateur radio operators, got their start in the hobby through simply listening to shortwave radio, or perhaps, to stations in the AM or FM broadcast bands. I suppose it is then inevitable that these two hobbies are bound to connect with each other from time to time. Here are a few examples of this that relate to my experiences.

In 1972, while doing a random band scan on shortwave, I came across a point-to-point radio station from Managua, Nicaragua that was transmitting a repeating test message (recording attached below):

The station was operated by the Tropical Radio Telegraph Company and I sent off a reception report in hopes of receiving a QSL from them. As luck would have it, the Plant Engineer, Guenter G. Zaenker, responded with a friendly letter including some details about their transmitter power and antennas used.

A couple of years later, when I got my amateur radio licence (VE3HLC), my SWL activities took a back seat to ham radio for a while. In 1978, I received a QSL for a contact with station YN1Z in Managua who turned out to be none other than Guenther G. Zaenker.

I worked Guenter for a final time as TG9XGV in Guatemala City, Guatemala. How is that for completing a hat trick!

Shortly after receiving my amateur radio ticket in 1974, I made a contact with station PJ9BN, Jack Van Sciver on the island of Bonaire in the Netherlands Antilles.

It turns out he worked at Trans World Radio, a broadcaster I had listened to regularly on the SWBC bands and it was quite exciting to discover this connection. Attached is a link to a recording I made of this station that same year as they were concluding a segment of their popular DX Special program:

https://archive.org/details/trans-world-radio-bonaire

It seems that Jack is still going strong as I recently found this link to his current amateur callsign NA3F: https://www.qrz.com/db/NA3F

A final note, I had made a 2-way contact through the Oscar 6 amateur radio satellite (uplink on 2 metres, downlink on 10 metres) in 1976 with W.G. “George” Roach in Ottawa, Ontario.

Some 11 years later, I was able to pick up station CFMO FM on 93.9 MHz, over 300 miles away, through some great ducting conditions. When I received a QSL from the station, it was signed by W.G. Roach who was the chief engineer at CFMO FM.

It certainly is a small world! I wonder how many others out there have experiences similar to mine?

Downtempo and warmth for your radio dial

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Hi to all SWLing Post community! FastRadioBurst 23 here letting you know what the Imaginary Stations crew are putting out over those airwaves this week.

On Saturday 18th January 2025 at 1200 hrs UTC on 6160 kHz and also on Sunday 19th January 2025 at 1000/1400 hrs UTC on 6160 kHz and at 2100 UTC on 3975 kHz via Shortwave Gold will bring you a one-off programme called Downbeat on Shortwave. Jesse Yuen and One Deck Pete bring you two 15 minute downtempo mixes each, so kick off your stress shoes and tune into some ambient and downtempo vibes and drift away.

On Wednesday January 22nd January 2025 at 0300 UTC via WRMI we have WARM 3 as an antidote to those cold winter nights. More heart (and feet) warming tunes from the Imaginary Stations boilerhouse maintenance crew. Here’s the trailer for the show.

For more information on all our shows, please write to [email protected] and check out our old shows at our Mixcloud page here.

Don Moore’s Photo Album: Chota, Peru

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Don Moore’s Photo Album: Chota, Peru

by Don Moore

More of Don’s traveling DX stories can be found in his book Tales of a Vagabond DXer.

For DXers of Latin American stations, the period from about 1978-1998 was the golden age of DXing Peru. Those years saw an explosion of shortwave broadcasting from small towns, especially in northern Peru. Most of the stations were unlicensed and few lasted long. I tell the complete story of the period in Tales of a Vagabond DXer. However, the book doesn’t have many pictures as that would have made it much more expensive to produce and to buy. Fortunately, this blog is a perfect place to share photographs.

In those days one of the biggest radio hotspots in Peru was the department of Cajamarca. Over one hundred stations broadcast on shortwave, however briefly, just from that department. Cajamarca is a special place to me because I visited the region in 1985 during the height of the radio boom and visited over a dozen stations in the towns of Chota, Bambamarca, Cutervo and Celendín and the city of Cajamarca.

Chota is the largest town in the central part of Cajamarca department and played an important role in the development of broadcasting in small provincial towns. It’s about 140 kilometers north of Cajamarca but in between is cold barren Andean altiplano rising to over 4,000 meters elevation. In 1985 the bus ride took twelve hours and we encountered ice storms coming and going.

In 1985 Chota was a sleepy Andean town in a fertile river valley.

Radio Chota was already seven years old when I visited in March 1985. The station only had a medium wave license but also broadcast unlicensed on the out-of-band shortwave frequency of 6296 kHz where it was widely heard by DXers. Later they received a shortwave license and were assigned 4890 kHz but several years passed before they actually switched frequencies. Radio Chota was a success story and is still on the air today. Most of the stations I visited in 1985 were not so lucky.

QSL collection of Don Moore … www.DonMooreDXer.com …

Radio Chota as heard on 6296 kHz in 1982 via On the Shortwaves:

Radio Chota as I heard it in Quito, Ecuador on 4890 kHz in 1997:

Radio Acunta was a more typical broadcaster of the period. The station broadcast irregularly in 1984 and 1985 with a homemade 100-watt transmitter. The station didn’t survive but the transmitter with its crystal-controlled frequency of 5800 kHz was a good starter set. Over the next several years DXers followed its movements around northern Peru as it was sold from one would-be station to another.

This picture with the homemade posterboard signs really captures the transient nature of broadcasting in rural Peru in the 1980s. Radio San Juan de Chota was on 5274 kHz for a few months in late 1984 and early 1985. I doubt they ever had permanent signs made. They did, however, have professionally printed envelopes.

Recording of Radio San Juan de Chota via On the Shortwaves:

Bambamarca is a smaller farming town 20 kilometers south of Chota. It was also home to several shortwave stations over the years. Radio Bambamarca had a short appearance on 5657 kHz in the mid-1980s.

Return to Chota

I always expected to return to the Cajamarca area someday. Finally, in November and December 2017, I revisited all the places I had seen in 1985 and more while researching my historical travelogue Following Ghosts in Northern Peru. A few months later, in May 2018, I returned to the city of Cajamarca and Chota with my DX travel buddies, John Fisher and Karl Forth. Continue reading →

HF Signal Enhancer for SDR: A Hands-On Build by Steve Allen (KZ4TN)

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Many thanks to SWLing Post contributor Steve Allen (KZ4TN), who shares the following guest post:

SDR Signal Enhancer

by Steve Allen

I came across this HF Signal Enhancer for SDR on the RTL-SDR.com website. It was designed and built by Peter Parker, VK3YE from Melbourne, Australia. Below is the link to the video of the signal enhancer in action using an RTL-SDR V4 Software Designed Radio;

www.youtube.com/watch?v=W6OXc_wZTXU

It was very easy to see and listen to the improvement to the signal reception the signal enhancer made. Having been a life-long shortwave listener and current SDR user, I had to build one.

I did a screen capture of the schematic, re-drew it using MS Word, and built the bill of materials. In Peter’s original design he included a T-R relay so you could use the SDR along with a transmitter, which I opted to leave out. I had the passive components in my “junk box” but had to source the enclosure, controls, and antenna connectors. I have used these clam shell extruded enclosures with previous projects and love the build quality and the fact that they incorporate a slot in the sides which let me insert a sheet of PCB material on which I can do the assembly.

Referring to the schematic drawing in Peter’s video, you can see that the variable capacitor “floats” above ground, which is not the usual application for these devices. To do that I mounted the vari-cap on a piece of non-plated PCB material that I cut to the width of the enclosure and it fit nicely within the slot. The vari-cap had three pins on the side of the frame that allowed me to force fit it into three holes I drilled in the PCB material. I was very careful to drill the holes undersize and then slowly open them up until the vari-cap press fit on to the board. For good measure I ran UV curing adhesive down into each hole, letting it flow all the way through before I set it with a UV light source.

I then drilled an oversized hole in the front panel for the vari-cap shaft to pass through.

I then mounted the RF gain and band switch. The next step was the assembly of the AM broadcast filter. As SDRs can be overpowered by local AM radio stations Peter choose to include an internal band pass filter that is configured for around 3.5 MHz. The intent of this filter is to attenuate the signals below 3.5 MHz. Strong AM stations will still be heard but there is much less chance of them bleeding through on the higher frequencies.

I assembled the filter on a piece of perf board and connected the component leads on the bottom. I passed leads back up through the perf board for the signal path and ground. I mounted it on the main board with a standoff.

The next step was the wiring of the inductors to the rotary switch. Simple, and I tied them to the vari-cap frame.

For the back panel I chose an SO-239 and a BNC for the antenna input, and for the radio connection an SMA and another BNC. I sanded off the coating on the enclosure at the antenna mounts as well as the four corners where the back panel screws into the top and bottom of the clam shell enclosure to provide good grounding of the enclosure. I wired the 1N4148 diodes on the antenna connectors, and attached the RG-174 coax. As Peter suggested, I grounded the long (relatively speaking) runs to and from the back panel with coax and grounded it at the back panel.

The last step was to apply a bit of epoxy adhesive to the fiberglass board and the slot it runs in to hold it in place. Once the epoxy set, I did the final wiring of the front and rear panel components. You can see how I sanded the corners of the back panel in the above photo.

I connected it to my inverted L antenna and an SDR Play RSP2 and gave it a test run. I like the fact that I can visually see the changes to the signal strength on the SDR software as well as audibly. It makes a noticeable improvement to the reception.

Thank you Peter. I enjoyed the build.

Steve Allen, KZ4TN

Turning up the heat on shortwave

Radio is Cheap Entertainment

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Source: Better Shortwave Reception, William I. Orr, W6SAI,
Radio Publications Inc., Wilton, CT, 1st Edition, p. 129, 1957.

A Radio is Cheap Entertainment

Digressions of Bob Colegrove

Radio is a cheap hobby. Consider the plight of concertgoers and sports fans. Today, the price of a ticket to a single event can easily equal or exceed the cost of a decent radio. Then, after the event, all you have left is a ticket stub and a memory. Further, if your team loses, the memory is probably not pleasant. Whereas, with a radio, you have a tangible item you can go on using as long as you want to. Perhaps by dividing some measure of enjoyment by the time engaged in the activity one could come up with a quotient indicating the relative value of various forms of entertainment.

I guess my point is an attempt to justify why I have more than the necessary number of radios. After all, it’s hard to listen to more than one at a time. But it’s also hard to put a number on ‘necessary,’ and besides, radios are cheap. It wasn’t always that way. In 1959, the entry-level shortwave “sets” were the five-tube Hallicrafters S-38E and the National NC-60 Special. These radios were marketed head-to-head at the $60 price point. To put things in perspective, that’s nearly $650 today. Conversely, a highly desirable Tecsun S-2200x (price, $372) with countless transistors would have cost less than $35 in 1959 dollars had it been feasible. An XHDATA D-220 (price, $10) would have been 92 cents.

I financed my purchase of a Hallicrafters S-38E using the device shown below. For those too young to recognize it, it was what passed for a lawn mower in 1959. It was very ecofriendly requiring neither gasoline nor battery charging. Instead, the short blade rotated, and the device moved forward on two metal wheels by manual exertion of pressure on the handle, which is shown at the top right. You had to overlap each pass across the lawn by at least ½ a blade width to get a decent cut. I had a clientele of three neighbor’s yards, each of approximately 1/6 acre for which I received $2 per mowing – $1 for the front and $1 for the back. There was no sales tax in Indiana at that time, and my earnings were under the minimum amount to pay any income tax, so you can do the math to see how long it took to buy my radio.

Fast forward 65 years. My neighbor’s boy rides on a 48-inch $3,200 mower with a cold soda in the cup holder; streams rock music on his noise-canceling, Bluetooth headphones; and knocks down $60 in about ½ hour. Radio? He thinks single sideband was a heavy metal group from Chicago.

Outside of an occasional set of batteries, there is very little continuing ownership cost for a radio beyond the initial investment. There is no monthly fee for Internet streaming or satellite radio. Whatever you care to donate to your local public radio station is your own business.

All of this is to say I have gone to some concerts and sporting events, but a fair share of my disposable income in recent years has been spent on radios, some of which, like entertainment events, are now just memories. The remaining radios festooning the shack are all necessary.

Bottom line: If your conscience is troubled by the prospect of spending money on a spare radio, or you are consumed with guilt at having done so, reassure yourself by considering what little would remain after any investment in a good meal at a decent restaurant. Just remember, for the sake of domestic tranquility, use discretion when sharing any plans with your spouse. In this situation, I often reflect on words attributed to the late Rear Admiral Grace Hopper, USN who used to say, “It’s easier to ask for forgiveness than permission.”

May your radio logbooks be enriched with many new entries in 2025.

Happy New Year!