Category Archives: QRP Radios

Want To Buy (WTB) Ads? Beware of scammers, they’re getting clever.

Over the past couple of years, I’d been casually watching the used market for a Kenwood TH-D72A handheld. Last summer, I started searching in earnest—I wanted one specifically for portable full-duplex satellite work.

For discontinued gear like this, instead of waiting for one to show up, I’ll often post a “WTB” (Want To Buy) ad on a classifieds site like QTH.com. In the past, I’ve had good luck with this approach.

This time around, I did eventually find a legitimate seller and now have a TH-D72 in my shack. But before that? I had to navigate several scam attempts—five of the six replies I received were from scammers.

And let me tell you: scammers are getting much more convincing.

Although this happened to me last year, in the past couple of months I’ve heard from several readers who’ve lost serious money through online classifieds—sometimes for high-end transceivers.

One story in particular prompted me to finally dust off this post from my drafts folder and finish it.

Please note: this isn’t a comprehensive guide. It’s simply a rundown of the real-world steps I take and the red flags I watch for. As scammers increasingly adopt powerful AI tools and become more sophisticated, I think it’s worth sharing how I approach online swap meets these days.

Rule #1: Assume Every Seller Is a Scammer Until Proven Otherwise

I walk into every transaction—whether I’m buying or selling—with a healthy dose of skepticism. That may sound cynical, but it’s saved me from a lot of headaches.

Scammers can pose as both buyers and sellers. They prey on your sense of trust, often impersonating legitimate hams. QTH.com knows this too; before posting an ad, you must confirm you’ve read their scam policy, which is packed with great advice.

Rule #2: Use QRZ.com to Vet Callsigns and Email

QRZ.com is the de facto database for amateur radio contact info. You need a QRZ.com account to view someone’s email address. If a person’s callsign profile has no email address listed, that’s a red flag. Scammers often impersonate real hams who don’t list an email—making it nearly impossible to verify their identity directly.

When someone replies to your ad, see how they contacted you. If they use your email from QRZ but don’t also reach out via the classifieds site’s internal classifieds contact form/messaging system (QTH.com or QRZ.com), be cautious. I usually confirm a response by emailing the address listed on QRZ.com directly and saying, “Hey—just confirming this reply came from you.”

Rule #3: If the Price Feels Too Good, It Probably Is

In my case, TH-D72A prices range between $250–$375 depending on condition, included accessories, etc. Some appear for $400+, but those rarely move quickly. The first day I posted my WTB ad, I got three responses: two were priced well below market. All three were scams.

Scammers study the market carefully. They want to offer something just cheap enough to be irresistible—but not so low that you question it. The key is to know your gear’s current market value, both new and used. If it feels like a steal, slow down and verify everything.

Rule #4: Call the Seller (They’ll Usually Be Glad You Did)

I make it a hard rule: I never send money to someone I haven’t spoken with on the phone. This may sound old school, but it works.

What’s more—I’ve never had a legitimate seller refuse a phone call. In fact, those calls usually help build rapport and trust. Most sellers are happy to chat about the gear, how long they’ve had it, what condition it’s in, and why they’re selling.

If someone avoids a phone call or keeps dodging it? That’s a major red flag in my book.

Rule #5: AI Has Made Scammers More Polished Than Ever

Scammers now use AI to clean up their writing, correct grammar, and even simulate a natural tone. The sloppy typos and awkward phrasing we once looked for? Those are becoming less common.

That’s not to say grammar is irrelevant—if a message sounds “off,” trust your instincts. But don’t rely on spelling alone to spot a scam. Assume a message might be AI-assisted and ask deeper questions instead.

Rule #6: Ask for Fresh Photos with Handwritten Details

Scammers often reuse real images from previous listings or scrape them from the web. I’ve had five scam replies with convincing product photos and callsigns printed on paper. But every single one was fake–they used AI or a graphics tool to superimpose a callsign on a what looks like a white sheet of paper.

What I now ask for:

Two photos of the item, from two different angles, with a handwritten note that includes:

  • The seller’s callsign
  • Their first name
  • The full date (month/day/year)

The note must be:

  • Handwritten on plain paper (no digital overlays or re-used images, no QSL cards because they’re easier to cut and paste into an image)
  • Placed next to the actual item, not just the box
  • Clear and visible in the same photo as the item

This request (mostly based on QRZ.com swap meet posting requirements) helps filter out scammers. Why? Because scammers almost certainly don’t have the item in hand—and they definitely can’t easily produce two unique images of the same gear and note from two different angles. This is something easily done by someone taking a photo of the item in front of them (simply reposition your camera for two shots). It’s extremely difficult to do this convincingly with AI.

As of mid-2025, AI-generated images still struggle with replicating specific devices like radios from multiple angles.

Bonus Tip: Compare the photo you receive to manufacturer stock images. If the item looks slightly off in terms of proportions, buttons, or layout, it might be AI-generated.

Here an example of an AI-generated image I requested:

The AI image, at first blush, looks reasonably convincing, but the notepaper is standing up on edge, the handwriting is super neat, and the image has a surreal quality to it—not like a real photo.

Of course, comparing the AI image with the actual Kenwood stock image (see below–taken directly from the Kenwood website) reveals numerous product discrepancies in button layout, display, size, etc.

If a seller pushes back too hard on your photo request or seems annoyed? Consider that a warning sign. If they’re not comfortable with this low-effort verification step, they might not be great to deal with down the line either.

Payment: A Few Extra Best Practices I Follow

  • Use PayPal “Goods & Services” — never “Friends & Family” unless it’s someone you know personally.
  • Some sellers request Friends and Family (F&F) because they don’t wan to to pay the PayPal fee. If this is the case, I add 3% to cover the G&S fee if needed.
  • Avoid Zelle, Venmo, or gift cards unless it’s a local, in-person exchange–say, at a hamfest or convention.
  • Again, always talk on the phone before sending payment. It’s always a bonus verification if the sellers’ area code matches their QRZ physical location.

In Closing

The online ham classifieds are a great way to find gear—especially discontinued or rare items that don’t often pop-up at local hamfests. But the environment is changing. Scammers are adapting fast, and AI is helping them sound more convincing than ever.

I still love buying and (on rare occasions) selling gear this way—but I walk in carefully. This post isn’t a masterclass in fraud prevention, just a collection of my habits, red flags, and lessons learned. I hope it helps someone else avoid falling for a scam.

If you’ve got tips of your own, feel free to share them with us in the comments section. Let’s keep the community strong and informed.

Stay smart and safe out there—good hunting!

—Thomas (K4SWL)

New Summer, New Radio: Field Testing the Thunderbird

by Sam Duwe (WN5C)

I really like homebrew radio. I’m also seeing a pattern: I build through the winter and the spring, get rusty at CW, and then spend the summer operating POTA until my ears bleed. So it’s good to be back! Here’s a quick report of a new radio I built and its maiden voyage.

For the past eight months I have worked on what I call the Thunderbird (v2) named after my local state park, Lake Thunderbird. It’s an 8-band (80-10 meters) 5-watt CW transceiver with SSB receive. I emphasized the latter (decent crystal filter and big speaker/audio amplifier) because while I don’t often use a microphone, listening to voice is both comforting and exciting – I love when the VK and ZL stations drift in late at night. It also works as a somewhat competent general coverage receiver for short wave listening. I built it to operate both in the shack and on a picnic table, it unfortunately is a bit heavy because I got greedy and kept adding bands.

I guess I “designed” this radio, but as I discussed before on this site I’m just a guy with no engineering background who learned to solder and read a schematic diagram. But by doing so I could understand and modify the clever circuits from the radios we love and then figure out how to make them play nicely together.

I built the radio using Manhattan construction on copper boards, and then stacked these and fit them into a metal project box with 3D printed front and rear panels. It’s a bit fiddly and messy, but I feel like I’m ready to challenge my family to a game of Operation! The nice thing about stacking the boards is that I can shield the receiver from the transmitter and digital components.

The bottom board houses the band-pass filters, receiver, and audio chain. This was my first attempt at building a superheterodyne receiver so I was a bit nervous (although this video calmed me down). The receiver takes inspiration from John Dillon’s (WA3RNC) TR-35. He uses a clever design to narrow (for CW) and widen (for SBB) the crystal filter. I also cribbed his excellent idea for the LED signal-strength meter. The audio chain was modified from the Elecraft KX1 which includes an AGC circuit. I learned last summer how important AGC is when I was on Vail Pass in Colorado and actually fell out of my chair and groaned in pain when a guy with an amp called me back. I also hand built an NM0S Hi-Per-Mite to switch in when I want a steep 200-Hz filter. This is an awesome circuit that you can buy in kit form.

Like I mentioned, I got greedy and experienced project creep. Honestly, I would have been super happy with 40, 30, and 20 meters, and 17 would be nice. But so would 15, and 10, and even 12 (a band that I only have a handful of contacts on ever). And why not 80 meters? So I modified Steve Weber’s (KD1JV) Tri-Bander relay-switched band-pass filter design to add them all. I also figured out how to build a preamp for the high bands. I built a secondary audio amp to drive a 3-inch 3-watt 8-ohm speaker for annoying my family at night.

The lower board with the receiver, band-pass filter board, and audio chain.

The top board houses the transmitter and the digital components. The transmitter is based on Steve Weber’s design because it’s perfect and is used in some form by many QRP CW rigs. It gives me between 4-6 watts output on all bands. Like with the receiver, I used his design for the low-pass filter board.

The heart of the transceiver is an Arduino/si5351 combination and the Arduino code written by Paul Taylor (VK3HN). Besides doing the heavy lifting of aiding me pull audio out of the ether his code and associated circuits are versatile and clever, including automatic filter switching, CW messages, and both keyer and straight key support.

Although I am mildly terrified of AI, ChatGPT helped me add all kinds of bells and whistles (on my own I’m not a very good programmer) such as RIT, audio filter switching, keyer speed control, and a simple but detailed display that shows the relevant information. The panel controls are all knobs and switches.

The upper board with the transmitter, low-pass filter board, and digital components.

Between the sub-par band conditions as of late, and my neighborhood’s increasingly nightmarish RFI, testing the radio’s real-world performance was difficult. Luckily I have an IC-703 on the bench and it keeps me sane. The Thunderbird isn’t as good but it’s maybe 85% of the way there (when I turn off the DSP and noise blanker on the Icom)? It has been disconcerting when 10-meter FT8 isn’t coming through, but apparently that’s the sun’s fault and not mine. But this radio was built for POTA, so onwards to my park!

For an activation it was a rush job. I had just finished with the fixing a few loose connections when I realized I had about an hour of time before picking my kid up from camp. So I headed to the park with the radio, my favorite easy-to-deploy antenna [QRPer affiliate link], and my ATU-10 (doubles both as a tuner and check to see if the radio actually works).

There has been a lot of rain here lately so my usual spot was underwater. As I was setting up on the high ground a car drove past me multiple times. I figured I was either in trouble or it was a ham, and fortunately it was the latter. Larry (WA5NTF) and I had a nice chat and he graciously drove across the bay to absolutely clean up on digital. For me, I spent about 30 minutes on 20-meters, got 25 contacts, and then failed on the high bands. This is my first solar-cycle peak: get it in gear, Sun.

A few observations: I really liked the speaker! I was away from others and could use it without invoking ire, and it was freeing. Same with the message function which helped because it wasn’t a day of pileups. I also am so used to an S6 noise level on 20-meter SSB that when I first started the radio I assumed it was broken, so quiet. What a difference being out of the city makes.

But it worked! I have some trips planned for the summer and fall to the Southwest so I can’t wait to lug this box to some weird places. And I’ll hopefully be operating locally quite a bit more. Hope to hear you on the air, hopefully on the high bands!

And a postscript, I’m not going to be a homebrew proselytizer, but if you have an inkling to try something new a great project is the SolderSmoke direct conversion receiver (I started with something similar). On this page there is a link to their active Discord server with friendly people and lots of guides on how to hand build a 40-meter receiver. Paired with a simple transmitter it would make POTA (even more) ridiculously fun.

72, Sam

Scott Compares the FTX-1 and IC-705

If you’re curious about the new Yaesu FTX-1 field radio and how it compares to the Icom IC-705, Scott (KK4Z) has been doing a deep-dive series over on his blog. So far, he’s taken a look at form factor, connectivity, and power requirements, but he will add more.

You can check out all of Scott’s FTX-1 posts here: https://kk4z.com/.

Highly recommended reading if you’re considering either rig for the field!

Steve’s MTR3B-V4 Field Kit in a Rothco Shoulder Bag

Many thanks to Steve (KV4AN), who shares the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page.  If you would like to share your field kit with the QRPer community, read this post.


KV4AN’s MTR3B-V4 Field Kit

by Steve (KV4AN)

The convergence of Solar Cycle 25, lots of great new equipment offerings, many active participants in Parks on the Air (POTA), Summits on the Air (SOTA), and compatible family outdoor activities make this a great time to be a portable High Frequency (HF) QRP ham radio operator.  To take advantage of this happy situation, I was recently able to purchase a MTR3B-V4 “Currahee” Mountain Topper transceiver, shown in figure (1).  The MTR3B-V4 is a miniature three band (40, 20, and 15 meters) CW only QRP transceiver made by LNR Precision.

Figure 1.  MTR3B-V4 “Currahee” QRP Transceiver.

Naturally, I had to form a kit around the new radio.  My three goals for the kit were: small size, lightweight, and self-contained.  Let’s see how I did.  You can comment below if I left something out or if there’s a better choice.

The kit consists of the following items, as shown in figure (2)–links to these items are at the bottom of the page:

Figure 2.  MTR3B-V4 Kit.
  1. MTR3B-V4 “Currahee” Transceiver – 40, 20, and 15 meter QRP CW Transceiver.
  2. Custom Faceplate Cover – A practical and reasonably priced custom faceplate protective cover.   I accidentally ordered the cover for the previous version of the radio, but Joshua had no problem with me changing the order to the new one.
  3. Morse Code paddle – This is a reasonably priced paddle with a fairly good feel that I had lying around when the capacitive knobs didn’t work out.  I plan to replace it in the future with the CW Morse SP4 POTA/SOTA N0SA design paddle, which is smaller and field proven.
  4. 3.5mm Stereo Cable – A 1.5 foot, 3.5mm to 3.5mm stereo (TRS) cable.
  5. Koss Earbuds – Nice quality stereo earbuds.
  6. Earbud Cord Organizer – I hated to add the extra item, but I got tired of untangling the  wires of my earbuds.  This clever item has solved that problem and is color coordinated with the slick line.
  7. All-Weather Notebook – All-weather notepad for copying QSO information in the field.
  8. Miniature Pen – This is a miniature pen that says it writes on waterproof paper.  It will also write upside down, although that may not be a feature you need during normal activations.
  9. Koss In-line Volume Control – An in-line volume control for use with the earbuds.  The MTR3B-V4 has a rudimentary volume control, primarily used to set the maximum volume level.
  10. Battery Pack Pouch – A small pouch that perfectly holds the battery pack and keeps all the components together and protected.  If you use Icom BP-307 or BP-272 battery packs, they fit perfectly too.
  11. Battery Cell Holder – An eight “AA” cell holder with a 9V-style clip.  Eight “AA” NiMH batteries will provide a nominal 9.6V to the transceiver.
  12. AA NiMH batteries – Eight 1.2V “AA” NiMH 2800 mAh Low Self Discharge (LSD) battery cells.
  13. 9V Snap Clip – These are good quality 9V snap connectors that also have the coaxial power connector required by the MTR3B-V4 already attached.  They are more durable than the ones with exposed thin red and black wires.
  14. Coaxial Adapter – SO-239 to BNC adapter for use when using other antennas with coaxial cables which have a PL-259 connector.
  15. Reliance EFHW “Bugout” Antenna – A very small and sturdy 40, 20, 15, and 10 meter End-Fed Half Wave (EFHW) resonant antenna.
  16. Slick Line – High visibility slick line, which ties to the arborist throw bag to get the antenna into a tree and then suspends it.
  17. Arborist Throw Bag – A well-made arborist throw bag with a good all-around weight.
  18. Gerber Mullet Keychain – An all-in-one minimalist tool kit.  Better than a sharp rock, as they say.
  19. Rothco Shoulder Bag – A military-style shoulder bag, just large enough to hold all the kit components.
  20. Battery Charger – The battery charger (not shown) is an eight cell NiMH charger.  It does not fit in the shoulder bag and is left at home.

Of course, it all had to fit in a tacticool bag.  I selected the small Rothco Excursion Organizer, The shoulder bag, shown in figure (3), has all the items from figure (2) in it (trust me).  Use the orange pen as a reference for the size of the bag.  Clipped to the “D” ring on the left side is the Gerber “tool kit”.  The pocket on the front left has the CW Morse paddle, the pen is in its place, and the zippered pocket on the right has the earbuds.  The back zippered pocket has the antenna and battery pack, and safely nestled in the main area is the MTR3B-V4 and an arborist throw bag.  There is a zippered sleeve in the main pocket that contains the cable for the keyer paddle, an adjustment Allen wrench, and the SO-239 to BNC adapter.

Figure 3.  MTR3B-V4 Shoulder Bag.

Conclusion

One thing you may have asked yourself is why I included a Morse Code paddle when the MTR3B-V4 has a set of capacitive touch knobs.  The answer is simple – they didn’t work for me.  I really wanted them to, but the pad of my thumb will not activate the “dit paddle” without moistening it first.  Even then, I have to press the knob hard at a point almost to the joint, which is not a natural code sending motion or feel and results in very sloppy code.

Another item I purchased, but decided not to use was a pair 9V 500 mAh Lithium Ion rechargeable batteries.  The voltage of this battery right off the charger is below the specified input voltage for the MTR3B-V4.

The battery is the area in which I am most concerned.  I’m concerned that the 9.6V NiMH pack may not provide enough voltage over an activation to keep the voltage above the specified minimum voltage of 9V.  I may have to go to a 12V LiFePO4 battery, but that will not fit in the current shoulder bag.  I may have to go with a larger bag or use a MOLLE system where I can strap together several pouches.

I think I’ve came close to achieving my three goals of: small size, lightweight, and self-contained.  I’ve not completed an activation with this kit yet, so I’ll see how it all works together in a few weeks.  I’m also looking forward to reading your comments and suggestions.

72,

Steve

KV4AN

Gear List Links

[Note: Most Amazon and CW Morse links are affiliate links that support QRPer.com at no cost to you.]

  1. MTR3B-V4 “Currahee” Transceiver (MTR3B V4 Currahee Mountain Topper)
  2. Custom Faceplate Cover (LNR MTR-3B-v4 Currahee Magnetic Protective Cover – Tufteln)
  3. Morse Code paddle (Black Pocket Double Paddle Morse Code Key – cwmorse.us)
  4. 3.5mm Stereo Cable (Amazon.com: Aux Cord 1.5ft, 3.5mm Aux Cable – Nylon Braided Audio Cable 3.5mm Male to Male AUX Cord Compatible with Car,Headphones, iPods, iPhones, iPads,Tablets,Laptops,Android Smart Phones& More (1.5FT) : Electronics)
  5. Koss Stereo Earbuds (Amazon.com: Koss 191651 KE5 Earbuds (Black) : Electronics)
  6. Earbud Cord Organizer (Amazon.com: ELFRhino Cord Organizer Earbuds Holder Earphone Wrap Earphones Organizer Headset Headphone Earphone Wrap Winder Cord Manager Cable Winder Green : Electronics)
  7. All-Weather Notebook (Amazon.com : GLORYFIRE Waterproof Notebook Tactical All-Weather Spiral Memo Paper Notepad with Waterproof Grid Paper for Outdoor Activities Recording 3″x5″ (5pcs) : Office Products)
  8. Miniature Pen (Amazon.com : Tombow BC-AP54 Pressurized Permanent Ballpoint Pen (Can Write on Wet Paper/Back), Air Press to Squeeze Ink Ink, 0.7, Orange : Rollerball Pens : Office Products)
  9. Koss In-line Volume Control (Amazon.com: Koss 155954 VC20 Volume Control, Standard Packaging, 39-Inch Cord, Compatible with Cell Phones and Headphones : Volume Control: Electronics)
  10. Battery Pack Pouch (Amazon.com : TRIWONDER Tactical Cigarette Pouch Molle Small Military Bag Battery Cigarette Case EDC Utility Card Holder Lighter Slot Mini Cigar Waist Pack (01 Green – 2 Pack) : Sports & Outdoors)
  11. Battery Cell Holder (Amazon.com: QTEATAK 2Set 8 x AA Thicken Battery Holder with I Type Wired Battery Clip Standard Snap Connector : Electronics)
  12. AA NiMH Batteries (Amazon.com: WENJOOP Rechargeable AA Batteries, 2800mAh High-Capacity NiMH AA Rechargeable Battery Long-Lasting Power, 8 Pack Double A Batteries Size for Household and Office Devices – 1.2 Volt Low Self Discharge : Health & Household)
  13. 9V Snap Clip (Amazon.com: CHANZON UL Wire 9V Battery I-Type Power Supply with Center Positive 2.1mm x 5.5mm Male DC Connector Holder Clip Converter, 5 Pack for Arduino, LED Strip : Electronics)
  14. Coaxial Adapter (Amazon.com: Ahoaepy 2PCS UHF to BNC Adapter, Low Loss SO239 Female to BNC Male Coaxial Cable Connector Adapter for CB Radio,Radio,Antennas.Extension Coax Cable : Electronics)
  15. Reliance EFHW Antenna (EFHW Bugout 56:1 40-10M Antenna – Reliance Antennas)
  16. Slick Line (Amazon.com : LiteOutdoors Guyline & Tensioner Kit – 1.8mm Diameter – 60 or 100 feet – Ultralight Reflective Tent Cord, Lightweight Non-Slip Cord Adjusters. Camping, Hiking, Paracord : Sports & Outdoors)
  17. Arborist Throw Bag (Amazon.com : SOB Outdoor Throw Weight Bag 250g Arborist Durable Climbing Rope Bag Multi Throw Bag Tree Rock Spelunking : Sports & Outdoors)
  18. Gerber Mullet Keychain (Gerber Gear Mullet Keychain – Multi-Tool Keychain with Pry Bar, Bottle Opener, and Wire Stripper – EDC Gear and Equipment – Stonewash – Amazon.com)
  19. Rothco Shoulder Bag (Amazon.com: Rothco Excursion Organizer Shoulder Bag, Olive Drab : Clothing, Shoes & Jewelry)
  20. Battery Charger (Amazon.com: EBL AA AAA Battery Charger, 8-Bay Individual Charger for NiMH NiCD Rechargeable Batteries with AC Plug Fast Charging : Electronics)

 

A Strong Case for the (tr)uSDX: Jamie’s Perspective

Readers, there’s a bit of a backstory to this guest post by my friend Jamie (AA4K). During the W4SOTA campout in October 2023, Jamie showed me his favorite field radio: the (tr)uSDX. I’ve used the (tr)uSDX for a couple of activations, but I’ll be honest—I haven’t exactly shown it a lot of love. I’ve even complained about its audio and receiver performance in the past. Jamie, on the other hand, really enjoys using his and makes a solid case for it as a field radio.

Jamie showing me his (tr)uSDX during the W4SOTA campout.

I asked if he’d be willing to write a guest post for QRPer, and he agreed (eventually!). When I saw him at Hamvention this year, he told me the article was ready—and in true form, he sent it to me via Winlink… using his (tr)uSDX.


A Case for the (tr)USDX

by Jamie (AA4K)

Introduction

There are many factors that must be considered when choosing a field radio. How big and heavy is the radio? How hard is it to repair or replace the radio if it becomes damaged or lost? How hard is the radio to operate? How power-efficient is the radio? Does the radio have the desired/required modes and features? Of course, the most fundamental question is, “Does the radio work?” I will try to answer these questions as I lay out… a case for the (tr)USDX as perhaps an almost perfect field radio.

The last two contacts on this page were with my friends Carlos (KB4CO, now AE2W) and Thomas (K4SWL).

How big and heavy is it?

The first question is an easy one. Aside from small home-brew radios such as K6ARK’s “Choking Hazard”, there isn’t a smaller or lighter commercially available radio out there that I am aware of. The (tr)USDX measures 112 x 61 x 50 mm (I trimmed the encoder post and used a lower profile knob), and weighs 5.3 oz, or 151 g. The next closest currently available commercial radio is perhaps the QRP Labs QMX. This radio is very comparable in size (110 x 64 x 38 mm) and cost, but it does weigh more at 7.3 oz, or 207 g. The more rugged metal case probably plays a big part in the weight difference.

(tr)USDX with a modified case I designed to use the radio as the antenna winder.

How hard is it to replace or repair it?

The (tr)USDX is often sold as a kit for about US$86 (+$20 for the case) [QRPer affiliate links]. Any repairs should simply involve desoldering affected components and replacing, or possibly just updating the firmware. I am a relative noob when it comes to kit building and this kit is honestly not very difficult to build… about one day. The instructions and support videos provided by the hardware developer, Manuel DL2MAN, are very thorough. I learned a lot about radios from building the kit. If you have no interest in kit building, the assembled radio can currently be purchased from Amazon for US$138, complete with a case. Whether purchased as a kit, or already built, the band pass filters on the radio board will need to be tweaked to get the most out of your radio.

How hard is it to operate?

The (tr)USDX only has 4 buttons including the rotary encoder: Menu, Encoder, Enter, and PTT. The Menu and Encoder cover the majority of the adjustments, and most of the time I don’t use the Enter and PTT buttons. The PTT functions only as a ptt or cw key depending on the mode (yes, if your key breaks mid activation, you have a built-in backup key). The single-layer menu system is simple to scroll through, and the most commonly used items are near the front of the menu.

The most challenging aspect of operation for some people is the tiny OLED screen which gets obliterated in bright light. Reading glasses do help, although when you become familiar with the menu are not as important. I would love to see a version with an e-ink display and, more importantly, a push-button wheel rotary encoder (to remove the protruding knob).

How power-efficient is it?

This radio sips power. I tested the radio I built using a LiFePO4 battery that supplied 13.56v. The current draw on receive is 66.1 mA, and 570 mA on CW keydown into a dummy load. A properly tuned (tr)USDX delivers about 5w on each of the five bands when fed ~12v. A set of three 18650s in series will provide the proper voltage and power the radio through many activations.

Does the radio have the desired/required modes and features?

The (tr)USDX is not for princesses. It is a minimalist’s radio. But if you start from the perspective of an ultralight backpacker who has to justify every gram in their kit, this radio checks all of the boxes. It is a five band radio (Low, Classic, and High band models available). It is capable of doing voice, cw and digital modes. Thanks to a beta update from the firmware developer, Guido PE1NNZ, this radio will interface with a computer without requiring a soundcard. One of my favorite features of the radio is the built-in SWR meter. With the SWR feature enabled in the menu, just put the radio in CW mode and press the PTT to find out if your radio is happy with the current antenna arrangement.

This photo was taken while sending the text of this article via Winlink to Thomas, K4SWL.

Does the radio work?

Although my total activation count is nowhere near as high as many of you, I have used the (tr)USDX for a majority of my successful POTA (156 as of this writing) and SOTA (72 as of this writing) activations. My confidence in this little radio was demonstrated when I used it on an ATNO activation of Admiralty Island National Monument (US-4537) in Alaska.

Conclusion

One reason why I like to participate in SOTA and POTA is that it gives me an opportunity to practice field radio deployment and operation with the goal of being ready to communicate anywhere and anytime. This level of readiness means that I have the necessary equipment with me all the time. For me, the (tr)USDX is my EDC (every day carry) radio. It can bounce around in my backpack (in its protective case, of course) and be ready to deploy if needed. If it were to get lost or broken, I can fix or replace it easily. And I find it to be easy enough to use with the understanding that it isn’t a luxury radio.

The author at ~11,000’ in Uncompahgre National Forest.

Video

Click here to view on YouTube.

(tr)uSDX Winder Case:

Click here to download the print file for Jamie’s the modified (tr)uSDX case.

New MTR-3B V4 Manual Now Available on LNR Precision Website

If you own the popular MTR-3B V4 transceiver, you’ll be pleased to hear that a new and greatly improved manual is now available on the LNR Precision website.

If you’ve recently picked up an MTR-3B V4—or if you’ve had one for a while and want clearer documentation—I highly recommend grabbing this updated guide.

Click here to view or download the new manual.

Parting Waves: My Last Activation with the Venus SW-3B

On Tuesday, May 6, 2025, I made a little time in my afternoon schedule to take my Venus SW-3B on a final POTA activation.

I might have mentioned in previous posts (and certainly on the Ham Radio Workbench) that starting in April, I’ve been trying to downsize the shack a bit. This is a process I go through at least annually. My shack/office is very small, so things pile up quickly—and I like to divest myself of gear as best I can.

During this process, one of my readers here on QRPer reached out and asked—on a whim—if I’d consider selling him my Venus SW-3B. I gave it some thought and decided to do so.

I love the SW-3B, but the truth is, I hadn’t used it in a long while. It’s been tucked away in my headrest kit for more than a year, and I just haven’t been reaching for it. That and, frankly, I’ve a couple of MTR-3B LCDs, an MTR-4B, and an MTR-3B Currahee model–I’m flush with super compact transceivers.

I agreed to sell him the SW-3B but told him I wanted to take it out on one final activation—and that’s exactly what I did!

Blue Ridge Parkway (US-3378)

I had to fit this activation into a one-hour window while my daughter was in a class. Fortunately, the class was no more than a mile from the Blue Ridge Parkway. Unfortunately, if I wanted a site with a picnic table for easy operation and setup, I wasn’t terribly close to one.

Luckily, I had my complete SOTA kit packed, including my Helinox chair and Tufteln knee board. With those two items—paired with the SW-3B—I could operate comfortably just about anywhere.

I picked a spot on the side of the road, very close to the parkway entrance from US-25. I knew the drive back to her class would take no more than three minutes.

I paired the SW-3B with my KM4CFT 30-meter end-fed half-wave, which includes a 40-meter linked extension. I figured with this antenna, I could operate on 40, 30, and 20 meters (by removing the link if necessary).

Lately, propagation has been flaky, so having a bit of frequency agility is key to a successful activation!

Gear:

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Radio:

Battery:

Key & Cable:

Other Accessories:

Camera & Audio Gear:

On The Air

I hopped on the air and started on 20 meters by calling CQ POTA.

Fortunately, 20 meters seemed to be in decent shape. Continue reading Parting Waves: My Last Activation with the Venus SW-3B

The POTA Babe Tries the CFT1

By Teri KO4WFP

Jonathan KM4CFT reached out to me recently to inquire if I was interested in trying his CFT1 QRP transceiver. The inquiry both surprised and delighted me as I’ve never had such an opportunity.

I nearly said no because I am no antenna expert and, as this rig has no internal antenna tuner, I’d need to learn more about antennas, SWR, and resonance.

My limited antenna experience dates back to when I first entered the hobby. I had ZERO antennas and no idea where to start. An acquaintance suggested I make a home-brew linked dipole and gave me a few pointers in doing so. I vividly remember limping through learning how to trim an antenna. That project taught me that I want as low a SWR as possible and to cut the antenna for the portion of the band on which I want to operate.

homebrew linked dipole

Those of you who read my articles here on QRPer know that I use an Elecraft KX2 for my field operations. I’m very happy with this radio and love that it has an internal antenna tuner. But the CTF1 does not. Here is where my hesitation and trepidation at trying this unit entered the picture. I figured the antennas I use on a regular basis might not play nice with the CFT1 and hence my reluctance to say “yes” to this opportunity.

“Craig”, my KX2

But this is ham radio, right? In ham radio, we relish challenges because they are opportunities to learn. This was my opportunity to learn not only about antennas in general but also to be more thoughtful as to how I deploy them in the field. This was an opportunity for growth.

I dug out the RigExpert Stick antenna analyzer I purchased nearly three years ago and tested each of the antennas I currently have, just for jollies. I understand that many factors impact SWR – height of the antenna, coax length, proximity of other objects, etc. For the purpose of this exercise, I just wanted a ball park idea as to what antennas I could or could not use with this rig without a tuner.

I found both the home-brew linked dipole and the Chelegance MC-750 would work fine. Out were the EFRW and AX1. As I’d been hankering for an EFHW in my kit, I purchased the Sparkplug EFHW and trimmed it. These kinds of projects intimidate me because I do not have much experience with them; however, one cannot learn what one does not attempt.

I used the CFT1 on three activations: April 25th at the Savannah National Wildlife Refuge (NWR) (US-0522) with the Chelegance MC-750, April 30th at the refuge again but this time with the Sparkplug EFHW, and Thursday, May 1st at George L. Smith State Park (US-2179) with the Chelegance again.

It was a warm day at the refuge on April 25th. I selected an open area in which I had set up in the past. There were wild blackberries growing directly under the oaks in the shade. The view was lovely and, when not engaged with the activation, the red-wing blackbirds, coots, and other birds kept me entertained. Unfortunately for me, the sun moved out behind the oak trees not long after I arrived and I soon called QRT to avoid being baked.

the field in which I set up
wild blackberries
cooter out sunning itself
water lillies in the impoundments
what is not to love about that view!?

I was pleased with the QSO map for this activation – 27 contacts on 40, 20, and 17 meters over the course of an hour and a half.

QSO Map for Savannah NWR 4-25-2025    Source: qsomap.com

My second experience with the CFT1 was on April 30th, again at the Savannah NWR, however, this time using the Sparkplug EFHW. I found a different spot, one I passed up before but was usable today as it was freshly mowed. There were wonderful, tall oak trees at this location which afforded shade and high, unencumbered branches for installing an antenna aloft. Continue reading The POTA Babe Tries the CFT1

Hamvention 2025 Day 2: I Couldn’t Help Myself…

Good morning, QRPers!

Day two of Hamvention 2025 was absolutely amazing—and the weather couldn’t have been more ideal. I wish I had time this morning to write a proper recap, but I’m grabbing a quick breakfast and heading back to the Greene County Fairgrounds for day three.

That said, I wanted to drop a quick note and share a photo of a little surprise from the Flea Market…

Even though I told myself I wouldn’t buy another radio at Hamvention, I spotted one I simply couldn’t pass up:

I already own a TR-35 (a rig I absolutely love), so I let that one go. But I didn’t have an MTR-4B in my collection… and that red chassis in the early morning sunlight? Irresistible. The asking price was $200—very fair, in my opinion—so I snagged it.

Later that day, I showed it off to my good friend Joshua (N5FY), and wouldn’t you know it—he gifted me one of his MTR-4B protective covers!

As soon as I got back to the hotel room that evening, I installed it.

She’s ready for the field.

 

I’ve actually wrote a review of an MTR-4B I borrowed from a reader. You can check out that review with links to field report here. I’m looking forward to taking this little red machine out to a summit soon!

More to come after Hamvention wraps up.

Thanks again to everyone who’s stopped by to say hello—it’s truly been the highlight of my weekend!

— Thomas (K4SWL)

The Yaesu FTX-1: Packages, Pricing, and Early Observations

As soon as reservations opened for the Yaesu FTX-1 via DX Engineering last year, I placed my order.

Details were sparse at the time, but we understood this would be Yaesu’s modernized successor to the beloved FT-817 and FT-818—the iconic bullet-proof radios that served the community for over two decades. Indeed they still serve me well!

This past week, new information surfaced via official Yaesu channels and FCC filings. A number of YouTube videos are already circulating, but I won’t be publishing anything myself until I have the radio in hand and can take it to the field.

That said, it feels like Yaesu was preparing for a full announcement anyway, especially with Hamvention less than two weeks away. Hamvention and the Tokyo Ham Fair have historically been the venues where major product launches from Yaesu, Icom, and Kenwood happen.

Summary & Observations

Before we begin: Here’s a summary of what we currently know about the FTX-1. I’m doing my best to keep things objective—there are no performance claims here, since no one outside of Yaesu has tested the radio yet. Some features suggest real potential (like the receiver architecture), but any speculation is clearly noted as such. Until we can get hands-on, this is simply an overview of confirmed details provided directly by Yaesu and its authorized retailers.

Note: All images are sourced from the Yaesu brochure. Pricing below is based on early estimates from authorized retailers and may be subject to change.

The FTX-1Field

(≈$1,499.95 US)

The field comes with Field Head with SBR-52LI (Li-Ion Battery), SSM-75E (Microphone), and DC Power Cables.

Via the attachable battery pack, the Field Head alone will output up to 6 watts. If a 12-13.8 V external power source is connected, it can output up to 10 watts.

FTX-1optima

(≈$1,899.95 US)

The FTX-1optima system includes: Field Head with SPA-1 (100 watt amplifier), SBR-52LI (Li-Ion Battery), SSM-75E (Microphone) & DC Power Cables.

That’s the only difference between the two versions: the inclusion of the SPA-1 amplifier. At least, based on the FTX-1 brochure (PDF).

As a QRPer, I initially discounted the amplifier. I typically run 5 watts or less and rarely exceed that, maybe once or twice per year. But after a closer look, I suspect many hams will opt for the amplifier version.

Here’s why:

  • 100 watts output on HF
  • 50 watts on VHF/UHF
  • Dual antenna ports
  • Built-in 2.5-watt speaker
  • Integrated ATU for 160–6 meters

I’m guessing–pure speculation here–the internal ATU is similar to those found in base rigs—likely offering a modest matching range, perhaps up to 3:1. That’s just my assumption as I place the order, and I’ll wait for confirmation once the unit is in hand. I would love to be proven wrong as we all appreciate wide-matching-range ATUs.

Another point in favor of the Optima: the $400 price difference between the Field ($1,499.95) and Optima ($1,899.95) packages is actually less than the standalone cost of the SPA-1 amplifier ($649.95), should you choose to purchase it later.

So, although I doubt I’ll use the 100W amp often, I’ve gone ahead and ordered the Optima package.

Accessories

Here’s a list of currently known accessories with estimated U.S. pricing:

FC-80 – HF/50MHz 10W Automatic Antenna Tuner – $319.95:


SCF-1 – Cooling Fan – $54.95


FC-90 – HF/50MHz 10W Automatic Antenna Tuner (for Long-wire/50Ω antenna) – $319.95 [Note: this appears to be a stand-alone ATU, not one that attaches to the FTX-1 directly. I’ll confirm.]


SPA-1: 100W Power Amplifier (supplied with FTX-1 Optima) – $649.95
MHG-1: Side Carry Handle (for carrying FTX-1 attached with SPA-1) – $14.99


FGPS-5: GPS Antenna Unit – $69.95
BU-6: Bluetooth Unit – $54.95
SSM-BT20: Bluetooth® Headset (BU-6 must be installed in Field Head) – $36.95
SBR-52LI: (no photo) 6400 mAh Li-ion Battery Pack – $199.95


One item I’m particularly interested in is the SPG-1 Protection Guard, which is Yaesu’s own front faceplate protector. No pricing info available yet at time of writing.

You know what?

Yaesu has genuinely surprised me here.

This is a more ambitious and modernized package than I anticipated—one that smacks of 2025 design expectations. The modularity is compelling: field operators can assemble the package they need without carrying unused features into the field. It’s an approach that sets it apart from many competitors.

The concept is simple but effective—when it’s time to hit the field, you just detach the FTX-1 faceplate from your base station setup, pack it in your kit, and you’re ready to go QRP. No additional cables to disconnect, no reconfiguration required. Clean, simple, and efficient.

If you’re someone who wants a 100W radio for field work but finds $1,899 steep, don’t overlook the FT-891—in my opinion, it remains one of the best values in the market at $630 US.

Still, the modular approach of the FTX-1 is refreshing. Snap the Field Head onto the amplifier and it becomes a base station. Detach it and you’ve got a capable QRP portable. Even a dedicated OEM front protection guard is offered.

Yes, it’s in the same pricing tier as the IC-705 and Elecraft KX2/KX3, but unlike those, the FTX-1 can be bundled with an OEM 100-watt amplifier—complete with dual antenna ports, a built-in speaker, and an internal ATU—for just $400 more. I love my Elecraft KXPA100, which pairs beautifully with both the KX2 and KX3 (and virtually any other HF radio), but it’s currently priced at $1,649.95 on its own.

Given that these units are manufactured in Japan, and I’m based in the U.S., I’m hopeful that these prices already reflect the 10% baseline tariff now applied to most goods from Japan. At the moment, I’ve seen no mention of surprise import costs—but that’s always something to watch.

What’s Next?

My order is in, and you can be sure that once the FTX-1 arrives, I’ll take it straight to the field and post a full field report and activation video. We’ll take a look at it together. Four to six weeks later, I’ll post a proper review.

Addendum: Yaesu USA Overview Video

Yaesu USA recently released an official video overview of the FTX-1, where they elaborated on several technical features.

One detail that stood out in both this video and the product brochure: the FTX-1 shares receiver architecture with the FT-DX10—a very capable transceiver with excellent RX performance. While I don’t expect the FTX-1 to match the FT-DX10’s filtering or front-end capabilities, this could bode well for its overall receiver performance.

Check out the video here: