Category Archives: News

Morse Code, New Products, News, Portable, QRP, QRP Radios, Reviews

The (tr)uSDX QRP transceiver: My initial impressions after a CW POTA activation

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I mentioned in a previous post that I placed an order for a (tr)uSDX kit with roWaves in February. My order was placed for a third production run kit and I assumed I would receive it sometime in March 2022.

Later that month, I discovered that DL2MAN announced AliExpress would sell both kits and fully-assembled versions of the (tr)uSDX. I used the link from DL2MAN’s website and ordered a fully-assembled unit.

My thinking was that I would receive the kit first, build it, then test the performance by comparing it with the factory-assembled unit. These units are so dang affordable I felt like I could splurge for both.

roWaves order on hold

I recently discovered that my (tr)uSDX kit had been placed on hold due to issues that popped up in the first and second kit group buys via roWaves.

Evidently–and someone can correct me if I’m wrong here–the first and second production runs kits had a component issue that equated to lower output power. In addition, Josh (KI6NAZ), reports that the early group orders had no boot loaded and the MCU was DOA.

I’ll patiently wait for roWaves to sort this out. I’m not in a huge hurry at this point because, frankly, my available time to build a kit has come and gone. The next few months, I’ve a lot of plans, travels, and projects to work through.

Fully-assembled (tr)uSDX

Much to my surprise, the assembled (tr)uSDX arrived Monday and I picked it up when I was at home on Tuesday of this week.

I was only home one night, but managed to do some quick testing.

I soldered Anderson Powerpole connectors on the supplied power cable pigtails. Next, I hooked the (tr)uSDX up to my variable power supply and a dummy load.

A quick test showed that I was getting about 3 watts of output power with about 13-13.2 volts, 3.25 watts at 13.8 volts, and 2 watts of power with 9-10 volts. This is lower than the expected 5 watts of output power @ 13.8 volts. The current consumption in receive however was about 60 mA even at 9 volts. That’s slightly below the published specs.

I honestly had no time that evening to play radio, but I took a moment to hook up the (tr)uSDX to my skyloop antenna just to check the audio quality in SSB.

As luck would have it, the first station I heard on 40 meters was a POTA activator in Ohio. He was calling CQ, so I couldn’t help but reply. I pressed the PTT button on the (tr)uSDX, spoke into the internal mic,  and he came back immediately with a 5×8 report. My meter was showing a max of 2 watts output power–the heavy lifting, of course, was done by the antenna.

This gave me a very good initial impression!

(tr)uSDX POTA Activation

The following morning, after running a few errands and carting my kids to some appointments, I left the QTH for a couple nights of travel.

I just couldn’t help but pack the (tr)uSDX and attempt a park activation en route. My goal was to see if it had enough positive receiver characteristics to be a proper POTA/SOTA portable rig–the feature set is comprehensive for a $135 radio.

I stopped by South Mountains State Park and paired the (tr)uSDX to an EFHW my buddy Steve (MW0SAW) kindly built and sent me. [Steve–I’m loving this antenna! Thanks again, OM!]

I made a video of the entire activation and will soon post the field report. I’ll push this video to the front of the line, but with my internet bandwidth, it might still be a few days before I can post it. Because of this, I thought I’d go ahead and share some of my experience with the (tr)uSDX in case you’ve been thinking of purchasing one.

(tr)uSDX pros

This little radio design has a lot going for it.

The chassis is very compact–perhaps the size of two Altoids tins stacked on top of each other. The encoder does protrude–in fact, it’s nearly as deep as the radio chassis. It’s not that the encoder is particularly tall, it’s just that the (tr)uSDX is so wee.

The radio has all of the CW adjustments you’d typically find in a compact field transceiver and even sports QSK (there’s also a semi QSK setting) with no relay noise. I assume it uses PIN diode switching.

(tr)uSDX Cons

Unfortunately, I did find a few negatives. The reviewer in me automatically gives the (tr)uSDX wide berth and a lot of forgiveness: we’re talking about a $135 transceiver here. I don’t think anyone is under the impression this would be a stellar performer.

In my opinion, the biggest negative is the (tr)uSDX audio. This little rig has a very high noise floor–perhaps S5 or S6.

The internal speaker is very modest and mine is incapable of producing audio at a level that is workable in the field where there are ambient noises like wind, water, conversations, birds, etc. The audio sounds decent when working a strong station, but weak stations are extremely hard to hear. If you turn up the volume on my unit beyond level 14, the audio simply squeals. I need to tinker with the volume control more.

Since the audio was so weak, I hooked up my Sony digital audio recorder to the (tr)uSDX headphone jack and made a separate audio recording for the upcoming activation video.

The headphone audio is louder, but there’s also a lot of noise in the audio amplification chain–again placing the (tr)uSDX noise floor around S5 or S6.

I was fully expecting the (tr)uSDX receiver to overload and it does. The variable filter helps and narrowing it makes the audio sound more pleasant in CW, but it doesn’t stop adjacent signals from bleeding through. Honestly, though? I could live with this and just use the filter between my ears if the audio was simply cleaner.

I also discovered that my unit needs alignment: the frequency display is off by 1.6 kHz in CW mode on 40 meters. I’ve put this on my to-do list–after all, this is a project radio meant for hands-on tweaking. I’m good with that.

One final point and minor quibble: the OLED display is very difficult to read outdoors. It’s superb indoors, but outside any sunlight or reflection simply wipes it out. To read the display I had to cover it with my hand.

The activation was a success: I worked 11 stations in 20 minutes or less, but I’m sure there were weaker signals out there I missed because they were simply buried in the (tr)uSDX’s noise floor.

I liked the (tr)uSDX keying, and I love the form factor, but I’m not sure I’ll ever use this radio again–configured as it is now–during an activation. For casual contacts, it could still be fun.

A little (tr)uSDX grace

I mean…$135 right?!?

The (tr)uSDX is an open source project and truly pushes the boundaries of what one can achieve for $135–again, even much less for the kit version. Frankly, I’m in absolute awe that any transceiver can be made below the $150 price point; especially a multiband, multimode transceiver.

The (tr)uSDX is an experimenter’s radio and I plan to dig into this little unit and see if there’s anything I can do to lower that noise floor. My hope is that the CPU or display may simply need better grounding or isolation. My time is limited at the moment, but I will open into this radio in the next few weeks.

In fact, eventually completing the kit build will give me an opportunity to explore the components and connections in much better detail.

I do know that my unit also seems to have the power output issue that some of the roWaves kits have. I can’t achieve anything better than 3.25 or 3.5 watts output at 13.8 volts. It should be about 5 watts at 13.8 V.

I would welcome your suggestions especially if you’ve built the (tr)uSDX kit or if you’ve put your assembled (tr)uSDX on the air and found that it had much better audio characteristics.

Antennas, Articles, Field Reports, Morse Code, News, QRP

Antenna Challenge #2: K6ARK End-Fed Half-Wave paired with the Elecraft KX1

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I mentioned in a previous post that my personal Activation Challenge for 2022 was “to build a new antenna each month and deploy it at least once that month during a field activation.”

In January, I built a doublet with a military fixture/winder.

For February, I decided to purchase and build a counterpoise-less end-fed half-wave kit from from Adam (K6ARK).  This kit is available on Amazon.com for a mere $19.95 (affiliate link).

The build itself is pretty straight-forward and not terribly complicated. With that said, you do need a fine soldering iron tip and a little dexterity to manipulate these super tiny components. Adam includes instructions for building an EFHW with a counterpoise, without a counterpoise, or a random wire antenna. The coil can be configured as a a 49:1 Unun, 9:1 Unun, or 1:1 Balun.

If you choose the EFHW route you will need to solder one surface-mount capacitor on the board. If you’ve never worked with surface mount components before, take your time and use a good magnifying glass.

Blue Ridge Parkway (K-3378 NC)

On Monday, February 21, 2022, on my way back from town, I hopped on the Blue Ridge Parkway and drove to one of my favorite roadside spots on a grassy hill surrounded by trees.

Since I configured the K6ARK kit as a counterpoise-less EFHW, I wasn’t entirely sure how stable the SWR would be in the field. For this reason, I was a wee bit nervous pairing it with my MTR-3B since that little radio lacks an SWR meter and really needs a good match.

I decided, instead, to pair the K6ARK antenna with my Elecraft KX1 which has a built-in ATU that can both monitor the SWR and find an impedance match if needed. Of course, I turned off the internal ATU for the activation, but if I needed it, I knew I could engage and use it. Continue reading Antenna Challenge #2: K6ARK End-Fed Half-Wave paired with the Elecraft KX1 →

Antennas, Morse Code, News, Product Announcements

QRPer Notes: Simon’s World Map Update, RG-316 Assemblies, My-Key-Mouse (USB), and Canary Islands VCAN

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Because I receive so many tips from readers here on QRPer, I wanted way to share them in a concise newsletter format.  To that end, welcome to QRPer Notes, a collection of links to interesting stories and tips making waves in the world of radio!

Simon’s World Map

Many thanks to reader, Mike Bott, who notes that Simon’s World Map has been updated to V1.2.3.

Click here to download Simon’s World Map.

RG-316 BNC to BNC assemblies

Don (W7SSB) shares two announcements.

First, he notes that Chameleon Antenna is now selling RG-316 assemblies with in-line RF Choke options and BNC fittings . They have a number of lengths available:

https://chameleonantenna.com/shop-here/ols/products/cha-50-coax-with-integrated-rfi-choke-cha-50-cx-wth

My Key Mouse

Don also notes that CW Morse is now offering a USB-CW keyer/ device interface called the My Key Mouse. Check out the product description:

New for 2022! Morse Code Key to USB Adapter!

Did you know that there is an ever growing list of Software and Apps that allow you to practice and/or learn Morse Code using Computers, Laptops, Tablets, Android and other devices? Truly a great idea, but, if you’ve ever tried using a mouse to send Morse Code, I am sure you’ll agree that it is makeshift at best. But why?

Because It takes the right tools for the job!
To Send Morse Code it takes a Proper Built Key Or Paddle.

Now You can practice with a host of software and apps using your own device!

Click here to read more.

Many thanks to Jesus Alberto de Lorenzo who shares a link to a fascinating field activity based in the Canaries: VCAN — a Volcano program!

Click here for full details.

Thanks to everyone for the tips!

News

Rare Find: Used Mission RGO One for sale

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Many thanks to Paul (VP9KF) who shares a link to a very rare find on the used market: a Mission RGO One. Not only is it a rare find, but it’s an extraordinary radio and is being sold by Larry (N0SA) a regular here on QRPer, and a very trustworthy fellow. 

If I didn’t already have a Mission RGO One, I would snap this up in a heartbeat. Here’s the add from QRZ.com:

I have decided to sell my RGO-ONE transceiver.

It is in like new condition and works as new. This one has the internal ATU and adjustable narrow filter installed.

I just don’t use it that much so I decided to sell it. Too many radios.

It will come in the original box with manual, mic and power cord. If you are not familiar with this radio just do a quick google search. I bought it used and I believe it is from production run number two.

Asking $860 shipped in conusa.
I take PayPal
Contact me at; n0sa@att.net
Larry
n0sa

If you’re not familiar with the RGO One, check out my full review on the SWLing Post. I’ve also taken it on numerous field outings–here are some reports.

It’s a superb radio and is only produced in small batches. Very few owners sell them and the price Larry is asking is quite fair!

Thanks again for the tip, Paul!

Field Reports, Morse Code, News, Portable, POTA, QRP

“The Elecraft AX1 antenna is just a dummy load!” Really? Let’s test that!

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Like a lot of QRPers, I love a good challenge.

Maybe it’s just in the nature of those of us who love QRP.

We get a small thrill out of seeing what we can accomplish with less.

AX1 Doubts?

On the morning of February 7, 2022, I received an email from a subscriber in South Carolina who had placed an order for a new Elecraft KX2 and an AX1 antenna package.  He picked this particular combination because he wanted the most simple and easy-to-set-up field radio system for impromptu CW POTA activations and a little random QRP fun.

He mentioned that, at his age, mobility is a bit of an issue and even though he knew a wire antenna would be more effective, deploying it while walking on uneven ground just wasn’t in the cards. The AX1 was a much more manageable and packable system. Plus, as he said, “I’m not going out to work DX. I just want to play and have fun.”

Only a week after placing his order, he was having buyer’s remorse which prompted his message.

He explained that he had exchanged emails with a friend in his radio club who told him he’d made a foolish mistake and that the AX1 was completely ineffective as an antenna and would only lead to disappointment. His friend said [direct quote here], “I owned [an AX1] for a month and was never able to make a single contact. It is really good at being a dummy load and nothing more! This thing shouldn’t be marketed as an antenna. It doesn’t work.”

I pointed out that I’ve used the AX1 numerous times in the field and have yet to be disappointed.

Before I used the AX1, I too, was very skeptical but after actually using it (instead of simply theorizing about it) I found it’s one of my most valuable antennas for a quick and fruitful activation. I pointed him to this playlist that includes all of my AX1 activations on YouTube. In all of these activation, I’ve limited myself to 5 watts as well even though the antenna can handle a full 10 or 15 watts from the KX2 or KX3.

I told him I’d been planning to pair the AX1 with my Mountain Topper MTR-3B and, it turned out, that very day a small window of opportunity opened in the afternoon. I told him we could both see how the AX1 might perform with three watts of power, especially since he’d planned to use 10 watts with his KX2.

As I’ve mentioned in the past, my motto is less theory, more practice!

We’d put the “dummy load theory” to the test! Continue reading “The Elecraft AX1 antenna is just a dummy load!” Really? Let’s test that! →

Antenna Tuners, News, Portable, QRP

Richard recommends the Phoenix QRP Pocket Transmatch

10 Comments

Many thanks to Richard (M0RGM) who writes:

Hi Thomas,

Hope this email finds you well, and thanks for all the recent blog updates and videos.

Like many other QRP ops we sometimes need an ATU or matching unit. For a while I’ve been looking for a small compact unit for use with my QCX-mini, MTR-3B and TX-500. I was sorely tempted by the Emtech ZM2, but they are quite expensive over here in England, especially as I’m awaiting delivery of a Venus SW-3B!

After much research I stumbled on the Phoenix Transmatch sold by Kanga Products. Paul, the proprietor, sells quite a range of quality QRP goodies. Having purchased the assembled device (work gets in the way of construction these days), I can say that this is a really good lightweight model that suits my purposes fully. No, it doesn’t have the tuning range of the ZM2, but I rather hope my antennas are not too far out of resonance!

For size comparison, see the attached photo taken whilst playing in the sunshine….

For anyone interested, the web details can be found at https://www.kanga-products.co.uk/ourshop/cat_1750054-QRP-ATUs.html

I have no connection with Kanga other than being a satisfied customer!

Regards,

Richard M0RGM

Thank you for sharing this, Richard. I love the size of Phoenix Tranzmatch–I was not familiar with it. It would be a great additon to pretty much any field kit. I see you also have the N6ARA paddles–I think they’re great!

It also sounds like you, too, have a QRP radio addiction. I hope you realize there’s no cure, so don’t fight it! 🙂

Thanks again for sharing this, Richard. 

Field Reports, Morse Code, News, POTA, QRP

POTA Fun: Pairing Mike’s “Oreo” Balun/EFHW with the Venus SW-3B

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A few months ago, Mike (KE8PTX), contacted me with info regarding his latest 3D-printed creation: a compact housing for an end-fed half-wave balun.

Mike’s 3D drawing

He called it the “Oreo Balun.”

Once printed, and after he wound the coil and installed the BNC, he sent this photo:

It’s cute, isn’t it?

He then surprised me by putting it in a padded envelope and sending it to me as a gift. Wow–thanks, Mike!

Oreo plans

End-Fed Half-Wave antennas are popular portable antennas for a reason: they’re effective!

They’re compact, easy to deploy, and resonant.

I only needed to attach some wire to the Oreo Balun, trim it, and hit the field!

Earlier this year, my buddy Vlado and I built two doublets with some scrap wire I had in my antenna parts box.  I measured the amount of wire I had left from that same spool. I knew it wasn’t enough length for a 40 meter EFHW, but I did think there was enough for 30 meters.

After giving it a bit of thought, I liked the idea of having a dedicated 30 meter EFHW. For one thing, 30 meters is a great band for field deployments and in the past this band has saved my bacon when either 40 meters or 20 meters was wiped out. Thirty meters is also a refuge WARC band during contest weekends.  In addition, a 30 meter EFHW is short enough that it could be deployed on most SOTA summits (which often have shorter trees).

Fortunately, I had just enough wire for 30 meters. IN fact, after trimming the antenna, I only had about two feet of wire to spare. It’s as if I had planned it! I would have never guessed that spool of scrap wire would have made two doublets and one 30 meter EFHW.

The next logical thing to do was take the Oreo to the field and play radio! Continue reading POTA Fun: Pairing Mike’s “Oreo” Balun/EFHW with the Venus SW-3B →

New Products, News, Portable, Portable Power

Bruce discovers roWaves ROW-PDS-0X USB-C to 12V converter boards

9 Comments

Many thanks to QRPer contributor, Bruce, who writes:

Hi Thomas,

I have been on a several-year journey to get to the point where all my portable electronics can be powered or charged via USB or USB-C. Gone are the days when I would have to lug around multiple chargers (or lots of spare batteries) in my travels.

Unfortunately, radios have been the holdout. I know that some people have played with USB-to-12v converter boards, with varying levels of success. I recently came across these dongles sold by the Romanian company roWaves Technologies:

Click here to check it out.

I just received a DS-02 (for FT817) and a DS-04 (for IC-705). I can now charge my 2m HT and marine VHF handheld using a USB-C charger or battery pack. I can now charge/run my IC-705 at 12v from the same source.

I have yet to explore how much noise these adapters generate. Even if just used for charging, they’re a great addition to my travel kit.

Probably not SOTA gear, but a nice addition to any ham’s travelling kit.

Bruce

Wow! Thanks for the tip, Bruce! I love how compact these are and it’s certainly a huge bonus that they can charge the internal batteries on your rigs. That alone, as you say, is huge because it can cut down on the amount of accessories needed during radio travels.

Let us know how well this works for you over time, Bruce. I’m curious if others have tried this USB to 12V converters–please comment!

Click here to check it out at roWaves.

Antenna Tuners, Articles, Field Radio Kits, Grab And Go, Kits, News, Portable, QRP, QRP Radios

Leo’s complete QCX-mini field kit and ZM-4 manual tuner kit

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Many thanks to Leo (DL2COM) who recently reached out after watching my livestream with Josh at HRCC on the topic of QRP/CW portable. 

Leo shared some photos of a complete radio kit he built around the QCX-mini along with a ZM-4 ATU kit he also recently built. Leo has kindly agreed to share these on QRPer.com.

Leo notes:

Attached is a photo of my ultra light kit.

It consists of a QCX-Mini 20m version (self-built), K6ARK EFHW, Palm Radio Pico Paddle, Eremit 2Ah LiFePo battery, headphones and a few cables.

I usually also carry a small arborist kit and if there is still room also the 6m mast from Sotabeams, depending on what I think will work best.

I chose a hard case and went for the Peli 1060 Micro. It has room for everything I need and it could easily hold a bit of RG316 coax in addition (even more if I chose to shorten the 30m arborist line).

The main benefit for me is that I really don’t have to worry at all about what’s inside – compared to a soft pouch. So I can just shove it into my backpack or glove box and forget about it since this configuration is a lot more rugged and water proof – while being slightly heavier. Continue reading Leo’s complete QCX-mini field kit and ZM-4 manual tuner kit →

Field Radio Kits, Field Reports, Morse Code, News, POTA, QRP, SOTA

SOTA: Breaking in the Venus SW-3B on Dogback Mountain & taking in Wisemans’ View!

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When I take a new radio to the field, I often don’t know what to expect until I arrive at the site and put it on the air. It’s one thing to use a radio in the shack, and quite another to use it in the field.

Earlier this year, I purchased a Venus SW-3B, three band QRP transceiver after much poking and prodding from readers and subscribers.  I actually contacted Dale (BA4TB) at Venus and asked for a loaner to do a review, but he had no units set aside for loans, so instead offered me a coupon code. I was hesitant to purchase yet another QRP radio–which is why I asked for a loaner–but his coupon discounted the radio enough I could even afford to splurge for expedited shipping.  He made money and I didn’t have to worry about loan periods, etc. It turned out to be a win/win.

I knew I wanted the SW-3B’s maiden voyage to be a SOTA summit, but I had to wait for a good weather window.

On Thursday, February 10, 2022, I got that opportunity!

Dogback Mountain (W4C/EM-066)

I learned about Dogback Mountain from my buddy Dave (W4JL) who activated it earlier this year. He told me it was a drive-up summit and was high enough to even rack up winter bonus points.

Back on January 26, 2022–during my POTA RaDAR run–I tried to activate Dogback Mountain, but the forest service road was too icy in all of the wrong places. I made it to within three miles of the summit but stopped and performed an activation of Pisgah Game Land and Pisgah Forest instead.

The road had no ice on it February 10, although it was very muddy and slippery in spots. Made for a very enjoyable drive in the Subaru, although post-activation you would have never guessed I’d washed the car the day before!

I arrived on site and parked the car at a pull-off that was well within the activation zone of the summit.  Dave was right: this summit was very accessible (well, as long as your vehicle has a bit of clearance–this isn’t a road for sports cars or low sedans).

I walked up the short path to the true summit and was absolutely gobsmacked by the views of Linville Gorge, Table Rock, and Hawksbill Mountain. Continue reading SOTA: Breaking in the Venus SW-3B on Dogback Mountain & taking in Wisemans’ View! →