Tag Archives: QRPer.com

“Anatomy of a Field Radio Kit” series on QRPer.com

If interested, I’ve now published both parts of my Anatomy of a Field Radio Kit series over on QRPer.com. This series was originally featured in the June and July 2021 issues of The Spectrum Monitor magazine. Here are links to both articles:

These articles primarily focuses on portable amateur radio field kits, but many of the concepts are ones I also use for my field portable receiving setups like this one.

I hope you enjoy!

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A simple guide to portable radio power

Over on QRPer.com, I just published a post on portable power that was The Spectrum Monitor magazine’s April 2021 cover article.

This article is essentially an overview of a few different types of rechargeable batteries including pros and cons of each chemistry.

While this article focuses on use in ham radio field applications, it also applies to anyone powering receivers–especially those without an internal power supply–in the field.

Click here to read at QRPer.com.

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Updates: Return of the lab599 Discovery TX-500, QRPer.com, and YouTube

Last year, I was lucky enough to obtain a lab599 Discovery TX-500 QRP transceiver to review for The Spectrum Monitor and the SWLing Post.

I could only keep the TX-500 for a one week evaluation period because it was one of only two or three pre-production units in the US–one was being evaluated for FCC approval.

Often, when a reviewer is sent a loaner unit, if we really like it we can purchase it from the manufacturer for roughly market price. The TX-500 was so rare, though, this simply wasn’t an option. Had it been, I would have purchased it. I liked the radio that much.


This week, I took delivery of a new TX-500 sent directly to me by the manufacturer in Russia. (You’d better believe I’m not sending this one back! I’ve already given it a name!)

If you’re interested in why I like the TX-500, check out my in-depth review here on the Post.

I will say this: if you’re a ham radio operator that likes SWLing, the TX-500 is a very capable broadcast receiver. Since I took delivery, I’ve had some pretty long listening sessions with the TX-500 on mediumwave and shortwave. The AM filter width is adjustable and can be quite wide if you want full fidelity. You must use an external speaker or headphones with the TX-500: this portable transceiver is sealed so that it’s weatherproof. The supplied speaker/mic works in a pinch, but I much prefer headphones or one of my amplified speakers.

QRPer.com: the other blog

I realize that many readers here on the SWLing Post aren’t aware that I actually have another blog dedicated to ham radio in the field: QRPer.com.

QRPer and the SWLing Post were actually born around the same time in 2008, but over the years I put much more effort and energy in the SWLing Post as I felt there needed to be better resources, articles, and information out there about radio listening. The SWLing Post has grown to a community of 8,000-9,000 daily readers and I couldn’t be more proud. There are days it really feels like a big, international family of kindred spirits. I’ve learned so much from this community.

QRPer is devoted to low-power amateur radio operation in the field. It has a completely different feel than the SWLing Post as most articles are field reports from my Summits On The Air (SOTA) and Parks On The Air (POTA) activations. I post at least one field report each week and typically test a different pairing of a transceiver and antenna. Many of my activations these days are using CW (Morse Code). After completing my first CW activation last year, I truly fell in love with this earliest of radio modes.

Click here to read my latest SOTA/POTA field report on QRPer.com.

I get that there are many here at the Post that don’t really care for ham radio or QRP operation and that’s perfectly fine. I mention QRPer because I’ve been getting notes from readers who are just realizing that there’s a common connection between the SWLing Post and QRPer: me!

I’m horrible at cross-promoting my work, so there you go.

Not a YouTuber, but I have a YouTube channel

While I’m at it: last year, I also started making real-time, real-life, unedited YouTube videos of many of my QRP field activations.  I made some of the first ones at the request of readers who wanted to know what it was like to actually perform field activations.

I’m a fellow who has very little free time and the thought of editing videos, frankly, makes me break out in a cold sweat. I simply don’t have the time. Plus, I don’t really have the personality of a successful YouTuber. I am what I am.

I posted my first unedited videos expecting negative comments. The total opposite happened.

While I never expect my YouTube channel to appeal to anyone beyond a very niche audience, I have gotten some very encouraging comments from subscribers who appreciate (virtually) sitting with me on the park bench or on a 3,000 meter summit and copying the CW and SSB contacts that roll in. I see these videos as supplements to my field reports on QRPer.com. In fact, if you want to see the Discovery TX-500 (mentioned above) in action, you’ll want to read my field reports on QRPer.com and watch the activation videos.

If you’re looking for a proper cure for insomnia, here’s a link to my YouTube channel. Consider subscribing if I haven’t scared you away already. 🙂 Indeed, as I publish this post, I see that I’m almost at the 3,000 subscriber mark. What?

Oh, speaking of YouTube and the TX-500, I made a video shortly after receiving it via DHL. I call it an “unboxing” video but really it’s an excuse to talk about why I’ve missed the TX-500.

By the way: I don’t monetize my YouTube channel, so there are a total of ZERO ads. I’m able to support my radio and blogging life via the backing of my amazing readers and sponsors. Thank you so very much!

Click here to check out the YouTube channel.

Do you enjoy the SWLing Post?

Please consider supporting us via Patreon or our Coffee Fund!

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Any advice on compact Lipo batteries, in-ear earphones with volume control, and portable amplified speakers?

The MTR-3B 3 band transceiver is about the size of a pack of playing cards.

SWLing Post readers: I originally published the following post on QRPer.com. I thought I might share it here on the SWLing Post as well since we’ve so many readers who regularly use compact battery packs, earphones, and portable speakers. I’m looking for some advice as I build a super-compact SOTA/POTA field kit around the Mountain Topper MTR-3B. If interested in helping me sort this out, read on:

I received my Mountain Topper MTR-3B last week, and I’ve already taken it on a POTA activation.

POTA Park Hampton Creek Cove

Last weekend, I decided to break it in on a POTA “two-fer” site: Hampton Creek Cove State Natural Area (K-6246) and The Overmountain Victory Trail (K-4577) in Tennessee. Hampton Creek Cove was actually an ATNO (all time new one) so it was a trial by fire!

POTA Park Overmountain Victory Trail

In short, the MTR-3B was marvelous. I’m so impressed.

As I mentioned in a previous post, I’m building a full SOTA/POTA activation kit for the MTR-3B. I already have a kit built around my KX2 and I don’t want to “borrow” any items from it (so I’m not surprised later in the field when an item is missing).

The TalentCell Rechargeable 12V 3000mAh Lithium Ion Battery Pack is the little black box.

For this activation, I powered the MTR-3B with this inexpensive 12V battery pack a friend recommended on Amazon.com (affiliate link). The battery pack is almost identical in size to the MTR-3B and works perfectly. The battery, charger and cable all set me back a whopping $25.

I also used my Whiterook paddle (which needs new paddle arms at this point) but that will soon be replaced with a set of N0SA portable paddles I recently ordered.

Since the MTR-3B has no volume control, I used a pair of 20 year old Sennheiser earphones I bought when I lived in Munich. These have been in a drawer for ages because I now prefer using in-ear earphones with silicon earpieces for better comfort and sound isolation. But the Sennheisers have one thing none of my other earphones sport: in-line volume control.

While the earphones worked well for this activation, I’d still prefer a set of in-ear earphones with in-line volume control. Any suggestions from MTR-3B owners? Also, I’d like a compact amplified speaker with volume control to carry as an option when needed. If you can recommend one, please comment!

I’m writing an article for The Spectrum Monitor magazine about portable power later this year. I noticed that a number of MTR-3B owners swear by 11V rechargeable Lipo cells that are used in the RC and drone markets. Many have a similar compact form-factor as the common 9V battery. I understand, however, some of these cells need special chargers and equipment to balance them.

I would appreciate any and all information about these batteries.

In the meantime, Rich (N8TGQ), recently shared a pic of his Mountain Topper portable pack. Check it out:


I think it’s brilliant how he’s mounted everything on a compact plastic cutting board inside the case. Rich says that what he loves about this set-up is that everything is there, ready to go–simply plug in the antenna!

Please comment or contact me if you have any suggestions as I build out a compact MTR-3B kit!

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Harold’s JA7HJ tower was not your average tower

The following post was copied from my ham radio blog, QRPer.com. I thought that SWLing Post readers would enjoy this article about Harold Johnson (W4ZCB) as well:

Harold's JA7HJ tower (Click to enlarge)

Harold’s 30′ JA7HJ tower (Click to enlarge)

I meet some very interesting people in radio circles.  My friend Harold Johnson (W4ZCB) is undoubtedly one of them.

Last year at my local ham radio/DXer club meeting, members were asked to bring photos of shacks and rigs, and describe our evolution as ham radio operators. In the series of photos that arrived at the following meeting, one in particular stood out: Harold Johnson’s radio tower in post-war Japan.

Johnson’s tower stood almost thirty feet tall and supported a 20 meter Yagi which you can see in the above photo.  Johnson, who at the time operated under the callsign JA7HJ, also had a little ham shack built. The shack materials–including the tower, Johnson recalls–cost him “three bottles of Scotch for the army quartermaster…I paid the Japanese builder $15 or $20 for the complete  enchilada.” This tower was built entirely of wood: the vertical members were 2′ x 4’s, the slats were 1′ x 3’s.

Of course, the tower didn’t have a mechanical rotor; instead, Johnson climbed inside the tower, lifted the wooden boom, rotated it manually, and placed it back on the uprights.

When asked how he powered his station, Johnson pointed to the wheeled generator in front of the radio shack in the photo. “The generator was called a B6B–it produced 24, 120, 240, and 480 volts, and was rated 10 kW.” When I asked how he managed to procure the generator, he replied that he “borrowed it from the flight line, which was about 300 feet away.”

Johnson's Nashville, TN shack, circa 1955/56. (Click to enlarge)

Johnson’s Nashville, TN shack, circa 1955/56. (Click to enlarge)

I always enjoy hearing personal histories in radio and I didn’t doubt for a moment that Harold Johnson’s would be intriguing, so I asked if he’d tell us how his interest in radio began. So, here’s Johnson’s story in his own words:

As a preteen, (and poor as a church mouse during our previous
Depression), I would visit my aunt and uncle in the summer, likely due to the fact that they were farmers and had food to eat. They owned an old Philco radio that had shortwave bands and I was intrigued with the phone amateurs on the 80 and 20 meter bands. Often, I could hear both sides of the conversation, after I found out that they were on various different frequencies, being crystal controlled back then! My…How times have changed.

In high school, I found another afficianado, and can recall melting “Woods metal” in boiling water and floating a piece of Galena on it until it returned to a solid and [thus] made my own crystal set. WWII had started by then, and I would listen to the ground-to-air communications between ships in Lake Michigan and pilots taking off and landing on them. Great DX, perhaps 10 miles away.

In 1943, I had graduated from high school and joined the US Army Air Corps. Went through training and was still in training (…to be a pilot until they counted airplanes and pilots and decided they had enough of each […so instead] turned me into a B-29 gunner). The war was over whilst [I was] still in training and I “retired” in November 1945. Went home and found my high school sweetheart, married, went back to school to finish my education and started the Johnson family. Still married, and
to the same girl. What a sweetheart to have put up with me all these years. [No kidding, Harold!]

Went back in the US Air Force in 1949, this time became a pilot, and just in time to go to Korea for a year. However, during training, had to learn the Morse and if you learned to 13 WPM, you had a free hour and didn’t have to attend class. That overcame my obstacle to amateur radio, and I took the exams in 1950 and became W9PJO. Our rules at that time were that you had to hold a “class B” ticket for a year before you could take the “class A” exams. That year I spent in Korea and Japan and managed to obtain my first foreign call, JA7HJ.

W4ZCBqslReturning home to wife and by that time two children, I took the class A exams and became W4ZCB. I decided that I enjoyed flying, (at least most of the time), and decided to make it a career. The ensuing years, I was always on and in the air, and usually spent the winters in Alaska and the summers in the Canal Zone, anything to practice how to be miserable. Lebanon in 1958, Vietnam in 1968 and by 1969 decided that I should start doing something else before my luck ran out.

During my last 4 years of service I flew an Army four star around the world four times. Fortunately he was Ted Conway, W4EII, and we mutually enjoyed operating under a couple dozen different call signs from a lot of exotic (and several not so exotic) places. Had G5AHB back when the 5 was reserved for foreign nationals. We were good friends after we both retired (on the same day; I always liked to say that he couldn’t stand to serve without me) until his death in 1990.

I started a small company manufacturing electronic test equipment for public utilities; spent the next 20 years doing that (and enjoying a much more stable life with family and radio.) Managed to work all the countries (entities these days) there are, win a few contests from a contest station I built and operated for 10 years. (80, 40, and 20 in the front room, 15 in one bedroom and since 160 and 10 were seldom open at the same time, they shared the other bedroom. To change bands, you just changed chairs. Five big towers and Yagis, a VERY  high maintenance hobby in the lightning prone state of Florida. (Let’s not mention hurricanes!)

Retired again to the beautiful mountains of North Carolina in 1986. A much more modest station these days, but active on all the HF bands. I really enjoy building homebrew radios and maintaining daily schedules with friends worldwide. Can be found daily on 21.203 with G3XJP and often joined by other builders of the magnificent PicaStar transceiver designed by him. Sixty-three years a ham, still enjoying it. It’s guided my careers and interests. What a wonderful hobby!

W4ZCB's shack today is based around his home brew SDR transceiver, the PicaStar. (Click to enlarge)

W4ZCB’s shack today is based around his home brew SDR transceiver, the PicaStar. (Click to enlarge)

Over the past few years, I’ve gotten to know Harold Johnson; I must say, he has to be one of the very few hams I know who knows the inner workings of tube/valve radios as well as he does the highest tech radios on the market, a rare talent indeed. If you’re trying to learn a bit more about the BC-348 series of radios and trying to diagnose a problem with it, Johnson’s your guy. If you’re trying to build an SDR from scratch, he’s also your guy.  And clearly, if you want to hear a fascinating account of a life influenced by radio, this is most definitely your guy.

Thanks, Harold, for letting me share your story!

Check out Harold Johnson’s website by clicking here.

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