Category Archives: QRP

If you’ve been reading QRPer for long, you’ll note that I’ve become quite a fan of the uber-compact Elecraft AX1 antenna.

Not only has the AX1 never let me down, but it can even outperform my other antennas in terms of snagging contacts during an activation. Yes, it can even work some DX as well.

Normally, I pair the AX1 antenna with my Elecraft KX2 (above) or KX3 (below).

I’ve even paired the AX1 directly to my Icom IC-705 using a homebrew simple capacity hat (thanks again for that idea LY2H!)

The AX1 needs a little help from an antenna tuner (ATU) to get a match across the 40, 20, and 17 meter bands. Of course, I could always mount the AX1 on a tripod and attach an in-line ATU, but I love the simplicity and speed of setup when paired directly to a transceiver that sports an internal ATU. To be clear, the Icom IC-705 has no internal ATU, but I was able to get away with using a capacity hat to match impedance on 20 meters.

The new Xiegu X6100 (above) has an internal ATU–a good one at that! As soon as I took delivery of this loaner unit from Radioddity, I plotted hooking it up to my AX1 to see how it might shake out in the field!

The X6100 lacks only one thing that the KX2, KX3, and IC-705 have: a good, accessible grounding point on the chassis. The AX1 needs a counterpoise to operate efficiently. Continue reading Pairing the Xiegu X6100 with the Elecraft AX1 antenna…will it work? →

Announcements, Kits, Morse Code, New Products, News, QRP

The new WA3RNC TR-35 4-Band 5-Watt CW Transceiver Kit

January 19, 2022 Thomas Witherspoon 9 Comments

Many thanks to Jim (N9EET) who notes that WA3RNC will soon be shipping his latest QRP transceiver kit: the TR-35.

According to the WA3RNC website, factory wired/assembled kits are available now for $379 US. The regular kits (with pre-wound toroids!) will be available for purchase January 24, 2022 for $279 US. If you’d like the pre-assembled version, simply click the checkbox that adds $100 for assembly in the WA3RNC store.

Here are a few TR-35 specs from the WA3RNC website:

- Size 5 ½ X 3 ¼ X 1 ½ less protrusions, weight 10.6 Oz
- 5 watts output on all bands at 12vdc input
- Full coverage of 40, 30, 20, and 17 meters with extended RCVR tuning above and below
- RCVR modes for CW narrow and CW wideband, and for SSB reception
- Optimized for operation from 3 series-connected 18650 Lithium cells
- RIT tunes + and – 5KHz
- Blue OLED display reads frequency to 10 Hz and RIT offset
- Built in Iambic keyer is adjustable 5 to 45 WPM with front panel control
- Separate jacks for straight key and paddles; Always ready for SKCC contacts
- Operates on 9.5 to 14 volts, < 100 ma receive, about 1 Amp Xmitt at 10 volts
- Selectable tuning resolution steps of 10, 100, and 1000Hz
- Low battery indicator with internal adjustment 9.5 to 11.5 volts
- Front panel adjustable RF gain control
- Front panel TX power control; Adjustable from 0 to full output
- Rugged TO-220 FET RF amp has delivered 5 Watts key down for 5 minutes
- Signal quality blue LED, RIT warning orange LED, Low battery red LED
- Excellent receiver sensitivity with MDS of -125dBm
- Very effective receive AGC prevents ear damage with strong signals
- Transmitter harmonics and spurs -52dB, meets FCC specs
- CW sidetone is the actual transmitter signal as heard by receiver
- Match the received signal tone to the sidetone for perfect zero beating
- Sharp IF filter; Better than 350 Hz at the -6dB point, plus 700 Hz audio filter
- Over 250 machine placed SMT parts, and about 55 user installed parts
- All critical circuits are factory pre-aligned and calibrated
- No endless “back menus”; There is a control or switch for every function
- Factory wired and tested option available
- All torroids are factory wound and prepared

Resources

I love the simplicity of WA3RNC’s designs! I’m sure this will be a popular little kit!

Comparisons, News, QRP

The Xiegu X6100 or the Icom IC-705? Making a purchase decision…

January 18, 2022 Thomas Witherspoon 27 Comments

Well before the new Xiegu X6100 transceiver was actually in production, I was already getting questions from readers and YouTube channel subscribers if they should plan to purchase the X6100 or the Icom IC-705.

The X6100 has been in the hands of early adopters now for about two months, so we have a good idea what the radio is capable of and how well it performs–at least, with the current firmware revision (January 18, 2022).

I’d planned to make a comparison video in a couple of weeks when the X6100 I purchased arrives, but as I was packing my loaner X6100 to ship to the next review last week, I got yet another email and made the decision to unpack the rig again and film a video comparison.

Not comparable?

Without fail, each time I do a radio comparison I get at least one email (often several) stating in no uncertain terms: “Thomas, you can’t compare those two radios!” Continue reading The Xiegu X6100 or the Icom IC-705? Making a purchase decision… →

Field Reports, News, POTA, QRP, Videos

Xiegu X6100: New compact throwline, POTA pileups & overloading in Pisgah National Forest

January 16, 2022 Thomas Witherspoon 23 Comments

On Thursday, January 6, 2022, I woke up with one goal in mind: take the Xiegu X6100 out on a proper hike-in activation!

While I’d had this radio on loan from Radioddity since December 23rd, I hadn’t had an opportunity to truly hike it into an activation site. Between the weather and my tight schedule, I haven’t had an opportunity to plot out a proper Summits On The Air (SOTA) Activation. SOTA activations that involve hiking usually take a much bigger bite out of my day and, lately, I’ve been to busy to plot one.

I do live near a vast trail network, however, and it so happens that much of the trails run through overlapping public lands: Pisgah National Forest and Pisgah State Game Land.

So I packed my Spec-Ops EDC tactical pack, grabbed Hazel’s harness, and headed out the door.

Hazel knows me too well.

When she sees my pack and my hiking boots, she waits in front of the door so there’s no possibility she’ll be left behind. Continue reading Xiegu X6100: New compact throwline, POTA pileups & overloading in Pisgah National Forest →

Hams, News, QRP

Dan’s QRP journey and report on the Venus SW-3B

January 15, 2022 Thomas Witherspoon 7 Comments

Many thanks to Dan (KE0ZAR) who writes:

Hi Tom,

I just finished watching your video on resonant/non-resonant antennas and ATUs. I enjoyed it a lot.

For context, I got my ticket in 2020 and got on the air at the end of July 2020. Since that time I have only worked QRP CW using a QCX (the original) on 20 meters and then after September 2021, I got a Venus SW-3B so I have done a bit of work on 40m and 30m now as well.

I really enjoy the challenge of QRP and in a bit over a year, I worked all states, as well as Japan, Canada, several Europe countries, etc, so with good band conditions, QRP really does work and is a lot of fun. My experience working /P stated when I got the SW-3B but I only got out 3 times as the weather up in the hills west of Denver got too chilly very fast; this spring I’ll get back to more /P. Continue reading Dan’s QRP journey and report on the Venus SW-3B →

Announcements, Kits, New Products, News, QRP

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

January 14, 2022 Thomas Witherspoon 8 Comments

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!

Field Reports, News, POTA, QRP

A Last-Minute, Late Afternoon New Year’s Day Activation!

January 12, 2022 Thomas Witherspoon 7 Comments

I’ve always believed that the first day of the year should be symbolic of the whole year.

At least, that’s the excuse I was using to fit in a quick activation on New Year’s Day (Jan 1, 2022).

I have had the new Xiegu X6100 on loan and planned to take it to the field, but that afternoon waves of rain were moving into the area in advance of a weather front. Since I don’t own this X6100, I didn’t want to risk getting it wet.

In fact, I had almost talked myself out of going on an activation, but my wife encouraged me to head to the Blue Ridge Parkway, so we jumped into the car and hit the road.

Our options on the parkway were very limited as they often are in the winter. In advance of winter weather, the National Park Service closes off large sections of the BRP because they have no equipment to remove snow/ice. Plus, you’d never want to drive the BRP in slippery conditions. There are too many beautiful overlooks to slide off of.

Thankfully, the Folk Art Center access is always open and incredibly convenient.

Blue Ridge Parkway (K-3378)

We arrived at the parking lot and I very quickly made my way to a picnic table while my wife and daughters took a walk.

I knew this would be a short activation even by my standards but hopefully, it would represent the first of many meaningful field outings this year! Continue reading A Last-Minute, Late Afternoon New Year’s Day Activation! →

Antenna Tuners, Antennas, News, Portable, Portable Power, POTA, QRP, SOTA

“What battery, antenna, and ATU should I pair with the Discovery TX-500?”

January 9, 2022 Thomas Witherspoon 25 Comments

Many thanks to Vitor Morais who asked the following question in the comments section of my YouTube video:

Hi,

Greetings from UK.
I recently learned that POTA [is now in the] UK so I am really looking forward to it.

I also recently put an order for [the Discovery TX-500] so I am really excited as well.

I would like to create a very compact setup pouch for field use to pair with this radio; one that I could take to summits or parks and also travel abroad.

What battery and antenna would recommend?

Would you recommend an ATU?

Or would you compromise to fewer bands or pack a secondary antenna?

I love to know your opinion.
Thanks

Great questions, Vitor! In truth, these sorts of questions are easy to ask but quite complicated to answer due of the insane number of options and possibilities available. It’s impossible to cover them all so I’ll try to give you some suggestions based on what I tend to use in the field. Continue reading “What battery, antenna, and ATU should I pair with the Discovery TX-500?” →

Field Reports, Morse Code, News, QRP, SOTA

SOTA & POTA with the QRP Labs QCX-Mini and Packtenna EFHW on Flat Top Mountain

January 7, 2022 Thomas Witherspoon 16 Comments

When I head out the door to activate a summit, if it involves a long hike, I reach for one of my super compact QRP transceivers like the Mountain Topper MTR-3B, Elecraft KX1, or KX2. If you’re carrying your entire station and all of your hiking provisions in your backpack, it’s best to keep the load as light and compact as possible.

I purchased the single-band QRP Labs QCX-Mini last year specifically with Summits On The Air (SOTA) in mind. My QCX-Mini is built for 20 meters which tends to be my most productive SOTA band.

The QCX Mini has a rugged, utilitarian feel: basic controls, two line backlit LCD display, and a sturdy aluminum enclosure. It’s super compact.

One of the first things I did was build a dedicated field kit around the QCX-Mini. Everything–save my throw line–fits in my Spec-Ops Op Orders pouch:

After the QCX-Mini’s insane debut on Mount Mitchell in November, I was eager to hit the field with it again.

A window of opportunity opened on the morning of Thursday, December 9, 2021, so I packed my new Spec-Ops EDC backpack with the QCX-Mini kit and drove 1.5 hours to Flat Top Mountain off of the Blue Ridge Parkway near Blowing Rock, North Carolina. Continue reading SOTA & POTA with the QRP Labs QCX-Mini and Packtenna EFHW on Flat Top Mountain →

New Products, News, Portable, QRP

Overloading: The Xiegu X6100’s biggest negative

January 6, 2022 Thomas Witherspoon 18 Comments

I’ve had the Xiegu X6100 on loan from Radioddity since December 23rd, 2021. In that time, I’ve used it heavily in the shack and I’ve taken it on three field activations using a variety of antennas.

Overall, I think it’s a great little field radio.

I’ll be producing an in-depth review of the X6100 for The Spectrum Monitor magazine, but in the meantime I’m trying to bring up any points in advance that might help others make a purchase decision.

On that note?

Receiver overloading

Let’s face it: receiver strong signal handling and overload performance are important factors when you choose a radio.

No one buys a new radio and says, “I really hope it overloads easily!”

As the title of this post implies, the biggest negative with the Xiegu X6100–in my humble opinion–is that it is prone to overload when in the presence of a strong signal. It’s a shame the front end isn’t more robust.

I’ve noticed this from my QTH, especially when tuning the X6100 outside of the ham radio bands. Indeed, I recently made a post about this on the SWLing Post. In truth, though, all bets are off when we move into the broadcast portions of the HF spectrum. Transceiver manufacturers usually don’t guarantee performance outside the ham bands. It makes sense as the focus is placed on ham band filtering.

But I have noticed overloading on the ham radio bands as well.

Earlier today, I did a park activation in Pisgah National Forest with the X6100. Before my activation started, I could hear a local AM broadcaster punching through the X6100’s front end all over the 40M band. I think it was a station on 1010 kHz which is only about 4-5 miles away from the site as the crow flies.