Tag Archives: AE5X

QRPer Notes: TR-45L Overview by K2OM, 8 Year Old Isabella Works the ISS, and POTA with the CW Flea

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!


K2OM’s overview of the Penntek TR-45L (YouTube)

Click here to view on YouTube.

Tony (K2MO) adds, “I suggest adding this link to your TR-45L [videos in the field]


Isabella Payne’s amateur radio contact with NASA astronaut Kjell Lindgren on the ISS (YouTube)

Click here to view on YouTube.


POTA with the CW Flea/Belka twins (AE5X)

Check out this short article by John (AE5X) where he uses a CW Flea transmitter and Belka-DX receiver for a QRPp POTA activation. I love what John’s done here and I think I may have to give the CW Flea a go too someday.

Here’s the video that accompanies his blog post:

The FX-4L QRP SDR HF transceiver is on order!

This year, I’ve had a couple of readers very kindly offer to loan me their FX-4C transceivers to take to the field and review.

Those offers have been very temping because I’ve only heard positive comments from owners of this wee feature-packed SDR transceiver designed by Yu (BG2FX).

Earlier this year, I learned that Yu was retiring the FX-4C and would be introducing two new radios, so I decided to hold off on an FX-4C review for this reason.

My buddy, Don, informed me that the new radios were now available for pre-order, so I checked out the option on Yu’s website, and placed an order.

Details (features and specs) are still a little sparse because BG2FX is still finalizing the design and lining up production, but here’s a snapshot of the two models based on Yu’s preliminary info:

The FX-4CR

I was very pleased to read that my buddy John (AE5X) has one of these on order.

The FX-4CR can push 15-20 watts on most bands according to John, which is most impressive for a one pound radio that fits in the palm of your hand! It covers 80 – 6 meters, sports a color screen with a 48 kHz wide waterfall display, an internal sound card for digital modes, built-in speaker and microphone, 9 – 18 VDC input range, and even sports Bluetooth!

That’s an impressive array of features for $550 US (on pre-order).

The FX-4L

I pre-ordered the FX-4L and am told by Yu that it should ship by end of October or early November 2022. I wouldn’t be surprised if that’s an optimistic projection.

The FX-4L is essentially a more basic QRP version of the FX-4CR; it’s maximum output power is around 5 watts.

It’s very similar to the FX-4CR in many respects: it has the same display from what I can tell, covers 80 – 6 meters, has a wide voltage range 9 – 18 VDC, sports an internal sound card, and is super compact and lightweight.

The FX-4L doesn’t appear to have Bluetooth. Lu doesn’t mention a built-in speaker or microphone, but there’s an obvious speaker grill and even a small hole that might be a microphone. I’ll try to confirm this. Yu does note that there’s room in the chassis for the user to add a battery or ATU.

I’ve been more interested in the FX-4L because, as you likely know, it’s very rare for me top operate over 5 watts of power.

That said, I certainly see the appeal of a 15W+ radio like the FX-4CR.

(Many thanks to Yu for sharing all of the FX-4L photos above.)

Stay tuned!

I’m really looking forward to checking out the FX-4L and also reading AE5X’s assessment of the FX-4CR.

I’m curious if anyone else has pre-ordered one of these radios. Also, if you’re an FX-4C owner, I’d love to hear your comments!

Fold-out feet for the Penntek TR-35

I must thank my buddy John (AE5X) for this excellent tip.

I was watching one of his YouTube videos some time ago and noticed that he added fold-out feet to his Penntek TR-35.

Like John, I appreciate my radios sitting at a bit of an angle as I operate and these fold-out feet looked like the perfect addition to my TR-35.

These feet are designed for laptops which are much heavier than the TR-35 or pretty much any similar field radio.

They arrive in a small package with an alcohol wipe to clean the bottom of the radio. The adhesive pads on the feet are made by 3M and high quality. I doubt they’ll ever fail. Since they’re designed to allow airflow under a hot laptop, I believe the adhesive should withstand hot summer days in the field as well.

Continue reading Fold-out feet for the Penntek TR-35

Check out John’s review of the Penntek TR-35

If you haven’t already, hop over to John’s (AE5X) blog and read his review of the Penntek TR-35 transceiver kit.

John reviews both the build and performance. He even put the TR-35 on his workbench and measured a number of parameters.

In short, the little TR-35 does exactly what it sets out to do and packs a surprising amount of performance.

John and I actually had a TR-35 to TR-35 exchange a few days ago (if not mistaken, the photo above was taken after that exchange). I was lucky enough to catch him as he activated a POTA site in Texas. From this end, his TR-35 sounded fantastic.

Click here to read John’s report.

I’m putting together a review of the TR-35 which will likely appear in the May or June issue of The Spectrum Monitor magazine.  I’ll eventually send this little TR-35 back to WA3RNC (it was very kindly sent to me on loan) but I do plan to purchase his TR-45 Lite kit when it hits the market later this year. Why? Because I don’t have enough QRP radios, that’s why.

The new (tr)uSDX QRP transceiver kit by DL2MAN & PE1NNZ!

Oh my giddy aunt!

I just learned–via AE5X’s excellent blog–that Manuel DL2MAN and Guido’s PE1NNZ fork of the uSDX series of transceivers is now for sale in both kit form and fully assembled (projected in March/April) via the Romanian retailer/manufacturer roWaves.

Of course, it hit the web and everything is already sold out. John snagged a second production run one, though!

As John makes clear, this is not the Chinese uSDX version (that I recently sent back to the retailer due to its numerous issues). It’s a complete kit version of the uSDX sandwich transceiver.

I would encourage you to check out AE5X’s post for more details.

My oh my, we live in exciting times! I have been hoping that someone out there would kit up the original uSDX sandwich for all to enjoy!

Fully-assembled Mountain Topper rigs soon available from LnR

MountainTopperMany thanks to Chris (K4RCH) for passing along this message from Steve (KD1JV) at LnR Precision:

I am pleased to announce that the 3 band Mountain Topper will be commercially available as a fully assembled product from LnR Precision. They should be available for purchuse around the end of January and will cost $250.00

Steve KD1JV

If you’d like a peek at The Mountain Topper manual, click here to download (PDF).

Steve (KD1JV) is well-known for his brilliant QRP transceivers–$250 is a true bargain. Check out AE5X’s blog for more info about the MTR.

Thoughts on the Elecraft KX1 and comparing with the Ten-Tec HB1B

My Elecraft KX1

I’ve been meaning to write a post about my Elecraft KX1, because, of all of the rigs I own, it’s the most-often-used, thus the clear favorite in my stable. But:  this morning, I read John Harper’s (AE5X) excellent assessment of the Elecraft KX1 vs. the Ten-Tec HB1B. He provides some significant numbers to consider when comparing these two lightweight CW-only QRP rigs, and makes a great case for elevating the newcomer HB1B over the KX1–at least, for some readers.

I’ve had my Elecraft KX1 for over three years, and, in all honesty, absolutely love it.  But, let’s face it: if I didn’t have one, if I had never touched nor used one, I would be seriously tempted by the HB1B–for its price, for the fact that Ten-Tec sells it (I’m a long-time Sevierville radio fan), and for the fact that it’s not a kit. Oh, yeah:  and because it works very well.

However, having used the KX1 for so long, I know that the HB1B (at least in its current state) could not replace my KX1. But before I explain why, I would like to make some strong points in favor of the HB1B.

YouKits HB1B Four Band QRP Transceiver
The Ten-Tec HB1B

The Ten-Tec HB1B

At least on paper, the HB1B has better filtering, a better display, and generally speaking, more bells and whistles than the KX1. Best of all, it comes fully assembled.

Why is this last point an advantage–? For a number of talented QRPers reading this, building the kit is the best part!  I know, I get it…And to tell the truth, I want to be like you kit-builders out there!  But I am only now getting into kit building, and building my confidence in kit-building.  I’m sure there are many others out there like me. For these QRPers, please note: the KX1 is not a beginner’s kit. I did not build mine. When I bought my KX1, I purchased it from a KX1 beta tester and professional engineer. The soldering and overall build quality are top-shelf.

Moreover, no matter how great an Elecraft radio is, it’s only as good as the person who built it. If the builder does sloppy work, your rig’s longevity and performance may suffer. Since you’ll likely be taking the KX1 with you everywhere, and it’ll experience a fair amount of movement (aka, hard knocks), this is especially important.

If, like me, you’re not prepared to take on building a KX1, fear not!–you should simply purchase from someone who knows their stuff: Elecraft can suggest some builders (including the amazing Don Wilhelm, W3FPR) or you can simply purchased a used KX1 fully-assembled. Or, you can simply purchase the fully-assembled HB1B.

So, why do I not find the HB1B enticing?

Yes, the Ten-Tec HB1B comes ready to roll. Still, could it replace my KX1?  I don’t think so. Two HB1B deal-breakers for me:

  1. As AE5X mentions, there is no internal antenna tuner option.
  2. There is no way (at least, on this version) to attach paddles directly to the rig.

Portability + Simplicity = QRP Fun

Why are these features so important? Well, my KX1 has an ATU, four bands, and an attachable paddle. One of my favorite things to do with my KX1 is, while traveling, to pull it out of its Pelican case, toss a 28′ wire into a tree, and lay a ground wire. As I stand there, I can hold the KX1, tune the antenna (easily 40M and up, with the internal ATU) and work stations my favorite way: while standing up.  I can also (if I like) sit for a moment, then jump up again, walk a bit, and generally move freely–just not possible with sit-on-a-table units.

My Elecraft KX1 fits nicely inside the Pelican 1060 case. There's even room to fit an external Whiterock paddle.

Additionally, everything I need fits inside a Pelican 1060 case. The Kx1 itself is an all-in-one unit–nothing external to attach, unless I want to. Oh, and I can also operate the KX1 with gloves on in below-zero conditions.

Anywhere QRP

Why would I want to operate standing up? Fact is, where I go, I’m only operating for thirty minutes or so, and in places where there’s no convenient spot to settle down or get too comfortable. In many cases, I’m operating on a whim–when I can grab a few minutes in a busy itinerary, or on a hike or day trip. With the Kx1, this is remarkably easy to do. I can have my KX1 on the air in four minutes or less, in most cases–and that includes the time to hang a wire–!  Packing up is also quick. This kind of operation feels as free as flying a kite.  Spontaneity at its best.

Part of that functional synergy comes from the fact that there are no additional components to hook up (i.e., no external tuner, external paddles). With the HB1B, I would be forced to either build a set-up, so that I could stand and hold the transceiver, tuner and paddles, or I’d have to…sit down.

Wayne’s inspiration for the KX1

Thinking back to a Dayton Hamvention several years ago, I seemed to remember that Wayne Burdick, N6KR (co-founder of Elecraft) was inspired by just this sort of off-the-cuff operation. To confirm this, I asked Wayne, just this morning, if I was on track with that. He offered this very thorough (and insightful) response:

I had been designing portable QRP gear for my own use for many years, including the “Safari 4″ (documented in three issues of QEX magazine in 1990). The Safari-4 was 3x5x7”, but it was fully self-contained, including an attached keyer paddle, internal 1-Ahr gel cell and manual antenna tuner, wattmeter, SWR bridge, and 4-band coverage. But it was too large for backpacking. Later, I designed some far smaller rigs with very good performance for NorCal and Wilderness Radio, including the SST, NC40A, and Sierra.

Then I started Elecraft with Eric, WA6HHQ. After we had success with the K2 and K1, I pitched the idea of a smaller version of the Safari-4 to Eric.

There were two inspirations for this. Back in the 70s, W7ZOI (Wes) created his “Mountaineer”, which was a crystal-controlled 40-m QRP rig that was very simple to use, very small, and self-contained, in that battery and paddles were built in. But it had no VFO, no ATU, a single band, and no frills. Taking what we’d learned in the K2 and K1 designs, I figured we could pack a great radio into this same size using updated technology. It had to cover at least 40 and 20 meters, and the idea was to use latching relays to minimize current drain and simplify band switching. We also used a DDS chip for the VFO–not quite as pure as crystal control, but just as stable, and totally adequate for a portable radio.

The other inspiration was my idea for an attached, but easily removable and mechanically reversible, keyer paddle. This became the KXPD1. I literally woke up at 5 AM with this idea. I realized immediately that this was the enabling technology for a hand-held radio, and I got busy with the design.

Having spent time camping and hiking with other rigs, I also knew that the ATU had to be built in. This allows the use of ad-hoc, wire-in-a-tree antennas, which is the secret to quick setup. It was a challenge creating an ATU that’s just 1 x 5″, but it worked. We spent weeks refining the rig and the ATU to work with typical field antennas, adjusting the component values to cover 40 and 20 meters. When we added the 30-m module, we found that it handled this well, too.

Most of my KX1 operation involves not even sitting down. I literally stop on the trail at a scenic overlook, pull the daypack around and extract the rig, toss a wire into one or two trees, and I’m on the air. I love this kind of operation. I’ve gone so far as to operate while sitting in a tree (an “inverted vertical”–a dangling wire–works amazingly well). Having to futz with add-ons can be fun, too, but it discourages “instant” operation. I like to quote Ade Weiss, W0RSP,  from his book The Joy of QRP: “If there is a place, and you can get to it, you must operate from there.”

You can’t overlook performance and features, either. The KX1 is stable in all operating environments and draws only about 35 mA. It includes a variable-passband crystal filter that can be widened out to copy AM and SSB signals, and can even do cross-mode (transmitting in CW while receiving LSB or USB). It has a full set of frequency memories and CW message buffers. For blind hams (or when you’re too tired to keep your eyes open), the KX1 has a 100% Morse-audio-feedback system. I tested this firmware with my eyes closed, and the result was very well-received by the blind amateur community.

Thanks for the history, and your inspiration, Wayne. Love it!

The KX1's Tuning, RF, AF and Filter knobs are very easy to operate--even with gloves on!

When you hold and operate the KX1, this legacy is all too apparent. Thoroughly thought through–down to a built-in LED lamp for logging–and, without a doubt, the original inspiration for several radios that followed: the HB1B, the MFJ 92XX series, and the Hendricks PFR3.

My guess is that the next generation of HB1B will have some of these clever features.

In the meantime, if you’re in the market for an inexpensive, CW-only, very portable QRP rig, and you’ve no plans to embark upon impromptu operation, the HB1B could be your rig. Based on my experience with Ten-Tec, if they sell it, they’ll give you excellent customer service. That is the beauty of these two choices, both Elecraft and Ten-Tec are excellent companies to do business with.

I only think I’d give up my KX1 for…the new KX3, and I’m not even convinced I’d do that, yet. The KX1 has become my little travel buddy. Time will tell, though. Check back here–if I’m wooed by another QRP radio, I may eat my words.

By the way, as I mentioned at the beginning of this post, the inspiration to finally write down my thoughts on the KX1 came from John Harper (AE5X) who has an excellent QRP blog that you should certainly add to your favorites!  And thanks, again, to Wayne, both for his response, and for his original ideas that continue to make QRP so liberating.