Enroute to the site, I thought it would be a good test for the mAT-705 to attempt to tune the excellent EFT-MTR antenna (which is resonant on 40, 30, and 20 meters) on all bands above 40 meters.
After arriving on site, I very quickly deployed the EFT-MTR antenna using my throw line. I then hooked the EFT-MTR up to the mAT-705 ATU and connected the ATU to the IC-705.
After turning on the IC-705, I opened the menu screen and tried to engage the mAT-705 ATU. Unfortunately, the ‘705 didn’t recognize the tuner. I double-checked to make sure the control cable to the mAT-705 was secure–it was. After some head-scratching, I realized I must have left the ATU’s mechanical power switch in the “on” position while using it a few days prior.
This evidently depleted the mAT-705’s internal 9V battery. What a bummer!
I bragged about the mAT-705 in a previous post because, frankly, it is a very capable ATU–quickly finding matches from 160 to 6 meters on my random wire field antenna and horizontal loop antenna at home. It also has an incredibly sturdy aluminum enclosure. It’s a very capable ATU in terms of quickly and efficiently finding matches and, superficially smacks of superb build quality.
But if I’m being honest, my love affaire with the mAT-705 ended Monday due to a number of discoveries.
9 volt batteries
According to Mat-Tuner’s product description, the mAT-705:
“[I]s powered by an internal standard 9 volt alkaline battery. Power saving technology inside the tuner allows the use of the unit for months without replacement. No battery power is consumed by the unit when powered off.”
Turns out, they mean it saves power only with the mechanical power switch turned “off.”
This, in turn, means that the user must remember each time they use the mAT-705 to flip the mAT-705 mechanical switch off. If left in the “on” position by accident, even with no connection to the IC-705 and while not in use, it will deplete a 9V cell in a matter of a few days.
This is a significant issue, in my opinion, and is compounded by a few other design choices:
Complicated battery removal
There is no “easy access” to the mAT-705 battery. The user must use a supplied (standard) Allen wrench and unscrew the rear panel from the chassis.
As we mentioned in our previous post, Mat-Tuner actually has a procedure for opening the case and replacing the 9V battery in order to prevent the LED illuminators from falling out. I followed this procedure to the letter, yet the illuminators still fell out. They simply aren’t secured properly and would be very easy to lose if replacing a battery in the field.
Once open, you discover that the 9V battery’s holder is a piece of double-sided tape. Seriously:
In addition, the ATU board essentially “floats” in the chassis secured in slide-in slots. The problem is the back panel–which you pull to remove the board–is only secured to the ATU board with three wired solder points.
Even when I lay the board down carefully, gravity will bend those BNC connections.
I can’t imagine this holding up with multiple battery replacements.
No external power port
Given that battery removal will take a user at least 5 minutes, I find it a little surprising that there’s no external power port.
It would be no problem at all for me, if the 9V battery died, to simply hook the mAT-705 up to my portable DC distribution panel like I can do with other external ATUs. But since this isn’t an option, you’re simply out of luck in the field. Better carry spare 9V batteries!
Where the lack of an external power port is really an issue, though, is for mAT-705 users in the shack. If the IC-705 becomes one of your main radios, you’ll have to be very disciplined to turn it on and off each time you use it, else you’re going to be replacing a lot of 9V cells.
Command connection to the IC-705 is basic
It seems to me that if you build an antenna tuner specifically to pair with a radio via a dedicated control cable, the tuner could potentially:
derive power from the transceiver
or at least be told by the transceiver to turn completely off when not actively in use. Especially since once a match is found, it’s locked into position even if the mAT-705 has no power.
The mAT-705 can’t do either.
Is it a good ATU? Yes. But inside it could be better.
As I said above, my original review stands in terms of the mAT-705’s ability to match antennas, I think it’s brilliant.
But I can no longer recommend the mAT-705 until some of these design shortcomings are addressed.
I’ve never owned a portable ATU that required so much discipline from the user in order to preserve the battery. I’ve also never owned one that was so fragile internally. Most portable ATUs *only* turn on when finding a match and then either “sleep” or turn off when not in use.
And portable ATUs like the Elecraft T1, for example? Even have a convenient battery compartment for easy removal. (And, oh yeah, the T1 will run ages on a 9V!)
To add insult to injury, it’s one thing to discover that your mAT-705 ATU eats 9V batteries if left on but not in use, but it’s quite something else to discover your $220 ATU’s 9V battery is held in with a piece of double-sided sticky tape.
How long could this possibly function if you’re replacing batteries frequently in the field?
My hope is that Mat-Tuner will sort out this design and re-introduce the mAT-705 to the market. I’ve heard so many positive things about other Mat-Tuner models which is why I wanted to try one out with the IC-705.
Mat-Tuner ATUs are sold by respected retailers in the ham radio world (like Vibroplex, who loaned this model for review) so I expect they’ll address these concerns in the coming months. I’ll certainly post all updates here on QRPer.
Until then, I have to recommend skipping the $220 mAT-705 and instead purchasing the excellent ($160 kit/$190 assembled) Elecraft T1.
Thursday, I set out to test how long the Icom IC-705 could operate during a Parks On The Air (POTA) activation with one fully-charged Icom BP-272 Li-ion battery pack. This, following my listening endurance test.
I knew conditions were pretty terrible Thursday in terms of propagation, but that didn’t really matter. I intended to call “CQ POTA” in CW until the ‘705 finally shut down due to low voltage. In my head, I imagined this wouldn’t take much longer than 1.5 to 2 hours and during that time, despite propagation, surely I’d work 10 stations to validate the activation, right–?
Sandy Mush Game Lands (K-6949)
I picked Sandy Mush Game Lands as my test site. Since I’d been there before, I knew there were ample trees to hang the Vibroplex EFT-MTR end-fed antenna, and I knew I’d likely be the only one in the parking area as this site is secluded and this was not a designated hunting day.
Setup at the site was pretty straight-forward. I quickly deployed the EFT-MTR antenna–using my arborist throw line–in a “V” shape hanging over a high tree branch.
I picked the EFT-MTR because it’s resonant on my three favorite POTA bands: 40, 30, and 20 meters. Note that the IC-705 does not have an internal ATU.
Although I have an mAT-705 external ATU on loan to test, I didn’t take it to this first activation–I wanted to keep the set up simple for testing battery endurance.
On the Air
I started calling CQ at 16:30 UTC on the 40 meter band and set the IC-705 to beacon mode call “CQ POTA K4SWL.” No replies for 10 minutes. At that point, I discovered the POTA spots website was down for a scheduled upgrade (I have impeccable timing!), so I posted my spot on the POTA Facebook page.
Then my buddy Mike (K8RAT) sent a text message stating that the Reverse Beacon Network (RBN) had spotted me, but with a very low signal report. Hmmm….why would that be?
Note to IC-705 owners: zero watts is not zero watts!
I turned up the power to 5 watts (the max the IC-705 will achieve on a 7.4V battery pack) and was greeted by an instant CW pile-up.
What a blast! I started on 40 meters in CW, but eventually worked both 40 and 20 meters in SSB and CW. I then lowered the antenna, removed the SMA cap on the EFT-MTR coil, and worked 30 meters CW for the remainder of my time.
I logged my first contact at 16:28, my last at 18:18 UTC. So 1 hour 50 minutes of near constant operating.
The IC-705 battery pack was still going strong and had about 40% capacity left, but I simply ran out of time as I needed to run an errand in town, so had to shut down the radio and pack up.
I must admit: the IC-705 is doing a much better job managing battery usage than I would have expected. I’m guessing I could have operated for 3 hours or so at 5 watts without needing to recharge the BP-272 1880 mAh Li-ion battery pack.
I do believe I’ll invest in the larger BP-307 battery pack which has a capacity of 3100 mAh. It’s a pricey battery, though, at $130 US.
How does the IC-705’s battery endurance compare with the Elecraft KX2? I’m not sure yet, but I’m guessing the KX2 will have even better longevity as its current drain is less than half that of the IC-705. The KX2 will operate at 10 watts output for about 1 hour 15 minutes with the internal battery pack, before decreasing to 5 watts output. I’ve never tried a battery endurance test with the KX2 at only 5 watts.
Of course, with an external 12 volt battery, the IC-705 will pump out a full 10 watts of power as well.
Five watts and a wire–wow!
The biggest surprise of the day?
I worked stations from Oregon, and Saskatchewan to the Azores…in single sideband!
Here’s a map of my contacts–red signal paths are SSB, CW in green (click to enlarge):
This was one activation where 5 watts SSB actually snagged more DX than CW. Great fun!
While I’d like to think it was a little IC-705 “mojo” on its first field outing, in truth it had everything to do with the EFT-MTR antenna and what must have been a moment of propagation stability.
This was also my maiden voyage with the CW Morse Single Lever paddle. CW Morse sent this paddle, along with their double lever paddle and a selection of straight keys, for me to evaluate. If you’ve been considering an affordable, portable single-lever paddle, this is a brilliant one. I really enjoyed using it and the action is very easy to adjust.
I’m already regretting the decision to send it to my buddy Eric (WD8RIF) for a proper evaluation. (Just kidding, Eric! (Maybe.)) He only uses a single lever paddle for his numerous field radio adventures.
Eric will give this single-lever paddle a proper workout and give us a full report.
I must admit, I had a lot of fun with the IC-705/EFT-MTR antenna combo.
Of course, I’ll be taking the IC-705 to the field a lot in the coming weeks.
Feel free to comment and ask any questions you may have about the IC-705. I’ll do my best to answer them.
Weather in North Carolina has been absolutely stunning over the past week, with the exception of two days where the remnants of Hurricane Sally dumped torrential rain. Two cold fronts provided us with gorgeous clear skies and dry conditions before and after Sally’s visit.
Of course, what better way to enjoy the outdoors than taking my radios to the field?
Last Wednesday, after several hours of knocking out home projects, my wife and I decided to enjoy the fall-like weather and get lost in Pisgah National Forest. My daughters were also keen for a little outdoor adventure, waterfalls, and hiking.
And our canine family member, Hazel? Always up for an outing!
Of course, my wife was throwing me a bone as she knew I was chomping at the bit to try the new-to-me Chameleon Emcomm IIIantenna.
Up to this point, I’d never used a Chameleon antenna in the field.
Chameleon Antenna kindly sent me both the CHA Emcomm III and CHA P-Loop a couple weeks ago for an honest field evaluation (and disclaimer: at no cost to me).
And being honest? The overall length of the Emcomm III wire antenna was intimidating. I’m used to field-ready wire antennas that are perhaps 30-41 feet in total length. The Emcomm III has a 73 foot long radiator and 25′ counterpoise! Holy smokes!
In my head, I imagined the only places I’d be able to use the Emcomm III would be in an open park with large, widely-spaces trees.
Turns out, I was wrong.
Two things make deploying the Emcomm III a breeze–even in the middle of a forest:
1.) An arborist throw line: this piece of kithas revolutionized my field antenna deployments. Not only does it give me the ability to suspend antennas much higher than I could before, but also to raise/lower antennas with ease compared with fishing line.
2.) The Emcomm III also has a floating dielectric ring on the radiator wire that allows you to create a suspension point. In fact, there are a number of ways you can deploy the Emcomm III which, I see now, makes it such a popular antenna among POTA operators.
To the field!
The first activation was actually a “two-fer”–meaning, two geographically-overlapping POTA park entities.
Wednesday, September 16: Pisgah National Forest (K-4510) & Pisgah Game Lands WRC (K-6937)
Propagation conditions on Wednesday were so crappy I found myself breaking with QRP to run 40 watts with the Mission RGO One into the Emcomm III. (The Emcomm III can actually handle up to 50 watts CW, 100 watts SSB.)
I first deployed the Emcomm III by pulling the radiator over a tree branch about 50′ high with the balun and winder near the ground. I then unrolled the counterpoise stretched out on the ground.
After only snagging about eight contacts in 50 minutes (a very meager amount for the typical park activation), I decided to re-configure the Emcomm III Portable so that it would act more like a NVIS antenna and perhaps grab a few regional hunters on 80 meters. There was no way I was leaving the forest without my 10 contacts to validate the activation!
I reeled in the radiator and re-attached my throw line to the floating loop and reconfigured the antenna to roughly match this “V” shape with a lower (roughly 25 ft) apex point:
I used the RGO One’s internal ATU to match the 80 meter band 1:1.
I started calling CQ on 80 meters CW and, evidently, the POTA site auto-spotted me via the Reverse Beacon Network (RBN) because within a minute, I found myself at the other side of a mini pile-up! I very rapidly worked 8 stations–most of them were in nearby Tennessee. These were callsigns I was not used to logging because typically they’d be under my skip zone–a little too local.
It was nice to get solid copy on 80 meters without the deep QSB on 40, 30 and 20 meters.
The thing that struck me about the Emcomm III at this first activation was how easy it was to reconfigure in the field despite the lengthy radiator. The wire is Copper Clad KEVLAR PTFE (Telflon-coated) and doesn’t easily tangle. It slides so easily through the trees–there’s no coil or bulky bits to get caught in the limbs.
When packing up, it wraps around its built-in winder very easily. Kudos to the designer.
Saturday, September 19: Pisgah National Forest (K-4510) & Pisgah Game Lands WRC (K-6937)
Last Saturday, I wanted to try the CHA Emcomm III in a different region of Pisgah National Forest and see how well it might pair with my Elecraft KX2.
We found an ideal spot to set up: a forest service road that had obviously been closed the entire season.
I deployed the Emcomm III Portable in the same “V” configuration as I did during the first activation, but this time raising the apex of the “V” up to 45 feet.
It’s important to note here that being a random wire antenna, the Emcomm III relies an an ATU to get good matches on each band. The Mission RGO One’s internal ATU did a brilliant job finding matches and, turns out, my KX2 did as well.
In fact, before I started calling CQ, I moved across the bands to see if I could get good matches with the KX2 ATU. From 80-20 meters, I think the highest SWR I had was 1.3:1. (The KX series ATU is truly a benchmark in my book!)
That day, even though the weather was gorgeous, propagation was terrible. I read a few reports from experienced POTA and SOTA folks who couldn’t snag the needed 10 contacts for a valid activation earlier that day. There were contests and QSO parties on the bands so lots of signals–but more than once on the phone portion of the 40 meter band, I could hear two stations calling CQ on the same frequency and trying to work the same stations totally unaware of each other. Not a good day to play radio in the field and was starting to wonder if I could even snag my needed ten contacts.
Turns out, I had nothing to fear.
Since I could, quite literally, pick any band the KX2 could transmit on, I was able to float across the HF spectrum, call CQ, and the RBN would make sure I was spotted properly to the POTA network.
I pretty effortlessly snagged my ten, and then a number to boot.
When I seek a spot to set up in a national forest, I often look for forest service roads with locked gates. When I set up on an unused road, it typically means I’ll have a high branch to hang the antenna and also a little space to deploy it without touching other trees. Our spot on Saturday was ideal.
Again, hanging and deploying the Emcomm III was effortless. I did bring about 12 feet of paracord with me this time allowing me to tie off the end of the radiator if I chose the “V” shape.
Monday, September 21: Mitchell River Game Land (K-6926) & Stone Mountain State Park (K-2754)
Monday was another stunning weather day.
I decided I wanted to finally make a pilgrimage to an ATNO (All Time New One) POTA site I’d been eyeing for a few months: Mitchell River Game Land.
Because propagation was fickle and this site was a good 3 hour round trip from where I was staying with family, I planned to use the Mission RGO One and run 40-50 watts or so.
However, when I got to the site, I realized I’d left the RGO One’s power cable at home. Fortunately, I still had my Elecraft KX2, so 10 watts would have to do.
I found a large parking pull-off area surrounded by trees. There was a ton of room to deploy the Emcomm III.
I decided to extend the radiator in a sloping configuration and elevate the 25 foot counterpoise.
The configuration was Identical to the one above , but the balun/center winder and counterpoise were suspended about 4 feet off the ground.
I fired up the KX2 and started calling CQ on 80 meters. The RBN picked me up and the POTA site auto spotted me. In a couple of minutes, I snagged my first three stations, then I heard no other calls, so moved up to 40 meters where I worked a big pile-up of stations. It felt like a mini-DXpedition at times. I loved it!
I even hopped on the phone portion of the 40 meter band and worked a few stations, getting respectable signal reports despite unstable propagation.
This activation went so well and the weather was so ideal, I decided to fit in another park that was only a 30 minute drive and was new to me: Stone Mountain State Park.
The thirty minute drive was relaxing and reminded me how much I enjoy this portion of the NC foothills leading up to the Blue Ridge Parkway and escarpment.
By the time I reached the park it was 1:30 pm on a Monday and I essentially had the place to myself (even though in my head I was preparing for crowds).
I had my pick of picnic spots so I found the one with the highest branches. One shot with the arborist throw line and I snagged a branch that must have been 45-50 feet high.
I first deployed the Emcomm III by simply running the radiator over a tree branch and laying the counterpoise on the ground–much like I did in the first Emcomm III activation and deployment.
I started calling CQ and worked about 4 stations, then nothing. The bands simply died on me!
After 30 minutes, I reconfigured the Emcomm III into a similar “V” shape I used at Pisgah National Forest with the apex at about 40 ft and the center winder and counterpoise elevated about 3 feet.
After some persistence, I finished off my ten contacts and then packed up–I spent about 70 minutes on the air and needed to grab lunch!
I honestly believe I would have found this activation even more challenging if I didn’t have an antenna that could snag stations on the 80 meter band since it was in the best shape that afternoon.
Again, I was very impressed with how easy it was to reconfigure the Emcomm III.
Tuesday, September 22: Tuttle Educational State Forest (K-2754)
After staying two nights with my parents in the Piedmont of North Carolina, I made my way back home to the mountains Tuesday afternoon. Again, the weather lured me back out to make just one more activation! (Let’s face it: the weather is a bit of an excuse).
One of my favorite parks that’s only a 20 minute detour off my path is Tuttle Educational Forest. It’s never busy there and they have a large picnic area with ideal trees for hanging antennas.
After searching through my main field pack (a Red Oxx C-Ruck), I found a spare power cord that would work with the Mission RGO One transceiver.
I didn’t have a microphone, though. That’s okay: it would be a CW-only activation.
Although I had the park to myself, I didn’t want to take up a large portion of the picnic area by deploying the Emcomm III in a sloping configuration similar to my activation at Mitchell River. I decided, instead, to be space efficient and use the “V” configuration once again with the apex at about 35 feet and the counterpoise on the ground. By doing this, the antenna footprint could almost fit within my picnic table area (although my counterpoise did snake into the woods).
I can’t remember how long I was on the air, but I do remember it was a breeze logging contacts that afternoon. Very enjoyable. I do love the Mission RGO One–the receiver is amazingly quiet, sensitive, selective, and signals simply pop out of the ether. It also sports silky-smooth QSK. Again, although I’m 90-95% a QRPer, it’s nice to push the juice a bit when propagation isn’t kind. The RGO One will push 55 watts.
The Mission RGO One ATU also snags excellent SWR matches across the band with the Emcomm III.
Emcomm III initial impressions
This past week, I gained some serious respect for the Emcomm III.
What impresses me most is its versatility and robust quality.
Don’t get me wrong: it’s not a magic antenna or anything. It’s essentially a random wire antenna.
What makes it such a fabulous field antenna, though, is its configurability. That and its uncompromised military-grade construction.
I shouldn’t have been so concerned about the radiator length as it’s actually pretty easy to accommodate and helps make this an efficient antenna on the low bands. (Look for me activating parks on 160 meters this winter!)
I believe I can deploy the Emcomm III anytime I have a half-decent tree nearby. I believe I could also use my 31′ Jackite fiberglass pole to extend one end or even the middle of the antenna if I wanted to go NVIS, but I would have to be careful to accommodate strain relief since the Emcomm III Portable is made of heavier materials than my EFT Trail-friendly antenna, for example.
I’m not sure I’d ever reach for the Emcomm III for a SOTA activation when I’d need to take a close look at weight and size. But for POTA? It’s brilliant. And, of course, for emergency communications (as the model name implies). The Emcomm III would also be an excellent addition to a radio club’s antenna arsenal.
The Emcomm III, like all Chameleon products, is designed and made in the USA. Since they use military-grade components, you pay a premium. The Emcomm III is one of their least expensive products at $139 US. Is it worth the price? Absolutely. In fact, I’m thinking about buying a second one to keep in my camper.
I posted a quick announcement on the POTA website, and jumped in the car.
When I arrived at the park, I noted an excellent, easily accessible picnic site with a nearby tree to hang my EFT Trail-Friendly antenna. Since I hadn’t been to this park in many years, I continued driving to check out other potential POTA sites.
In the main parking lot, I spotted a ham radio operator’s car with a prominent callsign on the back window and a POTA bumper sticker. I couldn’t see their operating site from the parking lot and since we’re all trying to social distance these days, I didn’t bother searching for them to introduce myself.
While it’s certainly allowed to have two activators running a park at the same time, I really didn’t want to impose and certainly didn’t want to cause any QRM by operating on the same meter band.
I had a “Plan B” in mind in case the park wasn’t accessible. On the west side of South Mountains State Park there was another POTA site: the South Mountains State Game Land (K-6952). I started driving in that direction, then used Google Maps to help me locate the entry road. Turns out, it was an additional 35 minutes of driving! Still, it was a beautiful day so no complaints from me.
The road was typical of game land roads: gravel and washed out in places. I had to ford one creek. My Subaru had no problem doing this, of course. (I actually love off-roading, so secretly I hoped the road would be more challenging!)
About four miles in, I found a pull-off that was big enough for my car and had an ideal tree to hang the antenna. I backed into the site, opened the hatch on the Subaru, and used the trunk/boot as my radio table.
Although there was a fair amount of QRN on 40 meters, now that the G90 has an RF Gain control (with latest firmware v 1.74), I could easily mitigate it.
I worked a number of stations on 40, then decided to move up to 20 meters.
I was very impressed with the response on 20 meters as well. Fading (QSB) was very deep, however, so I kept contacts brief. At times, stations would call me, I’d give them a 59 report, and when they’d reply I could barely hear them (and vise-versa). It took a little patience and good timing, but I believe I worked everyone who called me.
In the end, I had a total of 27 contact in the log with about one hour of operating. Here are my log sheets:
After transmitting steadily for an hour at a full 20 watts, the G90 body was pretty warm to the touch, but it had operated flawlessly.
A great field radio
The G90 is a gem of a transceiver and has some features that make it ideal for field use.
For one thing, I love being able to keep track of my battery voltage on the display:
Also, the G90 has excellent selectivity. On both 40 and 20 meters, at times I could see adjacent stations on the spectrum display that would have bled over and created QRM on less robust receivers.
I also like the ability to control all of the major transceiver functions without having to dive into an embedded menu. Adjusting the filter, RF gain, attenuator, and pre-amp, for example, is super easy.
I love the spectrum display, too. In the field, it’s nice to be able to find an open frequency by simply watching the display for a minute or so before calling QRL or CQ. It also allows me to see when folks are tuning up nearby to make contact with me.
Although I’ve been using a resonant antenna in the field, the G90 has a very capable built-in ATU. Back home, I’ve used it and have been very impressed with its ability to find good matches. Yesterday, for fun, I was even able to get it to tune up the EFT Trail Friendly antenna on 80 meters! I doubt it would be efficient, but the ATU did find a 2:1 match.
The only two features I feel like the G90 is missing are a notch filter (both manual and auto) and a voice keyer. I’m sure a notch filter could be added in a future firmware update (others have been asking for this as well), but I doubt a voice keyer could be added as easily. In truth, the voice keyer is a bit of a luxury, but it’s a feature I use without fail on my KX2 since park and summit activations often require constant CQ calls. Being able to record a CQ and have the radio automatically send it allows the op to drink water, eat lunch, and relax between contacts.
The following article was originally posted on my other radio blog, the SWLing Post.
Earlier this year I published what I called an “initial” review of the CommRadio CTX-10 QRP transceiver, promising an eventual final review. The reason for this is that I sensed there were important CTX-10 updates on the horizon, and I wanted to re-evaluate the rig once the upgrades had been implemented through firmware.
I’ve been very pleased with the attention CommRadio has paid to their customer feedback on some of the most important requests.
Instead of reiterating what I wrote in the initial review, I’ll jump straight into the upgrades.
At time of posting my initial review, the CTX-10 didn’t have A/B VFOs. This was my primary gripe about the CTX-10, because without A/B VFOs, there was no way to operate split, which meant that you could not work DX stations that use split to manage large pileups. This is actually a really important feature for a QRP radio because during split operation, a pileup is pulled apart across a few kHz of bandwidth, thus giving a 10-watt signal a better chance of being heard through a collection of legal-limit signals.
On June 10, 2019, CommRadio released a firmware package that added A/B VFOs and the ability to operate split to the CTX-10.
Even though there are only a limited number of buttons on the front panel, it’s incredibly simple to enter into split mode:
Chose the frequency and mode;
Hold the STEP button for one second or more, then release. You’ll then see a split display indicating the TX and RX frequencies.
Use the left arrow key [<] to toggle between them.
I do like the clear TX and RX lines, which leave no doubt in the user’s mind what the frequency used for transmitting and receiving is. On some radios, this can be a bit confusing.
Split operation is simple and effective, thus I consider this issue fully resolved.
In my initial review, I noted that the CTX-10 ATU needed near-resonant antennas for the ATU to make a strong 1:1 match. Indeed, a number of times I actually used a near-resonant antenna in the field––the EFT Trail-Friendly, for example––and the ATU couldn’t get below a 3:1 match. For what it’s worth, CommRadio states that the CTX-10 can easily handle 3:1.
CommRadio has made modifications to the ATU function, improving the performance of the antenna-tuner algorithm, which had a significant impact on 80 and 60 meters. I’ve also had better luck with a number of field antennas I’ve tried on 40 and 20 meters. Is it as good as the Elecraft KX-series ATUs? No, but I consider those ATUs to be some of the most flexible on the market.
Having a built-in ATU on the CTX-10 is certainly a valuable feature in the field. When I need to match a challenging antenna with the CTX-10, I bring my Emtech ZM-2 manual tuner along for the ride. A perfect combo.
There still is no way to adjust the microphone gain control nor microphone compression on the CTX-10. Much like a military or commercial radio, the CTX-10 is optimized for just one style of mic: in its case, the modular MFJ-290MY or Yaesu MH-31A8J handheld mic.
The CTX-10 microphone input has a limiting pre-amplifier with built-in compressor and ambient noise gate–in short, the CTX-10 handles all microphone settings automatically.
Through firmware updates, a number of positive adjustments have been made to the microphone settings:
the microphone-decay timer has been tweaked so that audio clipping is less of a concern
audio clarity and gain have been improved
audio power has been improved resulting in .5 to .75 watts of additional peak power
microphone audio leveling has been improved
VOX attack and decay timing has been improved
These are all welcome adjustments.
I would note here, though, that if you plan to use a mic other than the MFJ-290MY or Yaesu MH-31A8J handheld mics, you will have a limited means of adjusting the mic parameters unless you have an external mic EQ. A number of readers, for example, have asked about using their Heil boom headset with the AD-1-YM cable adapter on the CTX-10. Boom headsets are a wonderful tool for field operation because they free your hands to log contacts. As for using boom headsets on the CTX-10, since I don’t have the appropriate adapter, I can’t speak to this. But since you can’t control mic gain, it might take time to learn how to position the boom mic and adjust your voice level for optimum performance.
As mentioned in our initial review, the CTX-10 does not support QSK/full break-in operation. Rather, the CTX-10 uses a traditional relay for switching between transmit and receive. During CW operations, you’ll hear a faint relay click when switching from TX to RX and back again.
This isn’t a problem for me, as I rarely set my CW rigs for full break-in, but the CW hang time delay on the CTX-10 is not currently adjustable. For high-speed CW ops that prefer a faster relay recovery, I suspect this could be an annoyance.
There have been recent CTX-10 firmware upgrades that have helped solve issues found with CW keyer timing in early units. I found the timing issues were mainly present while sending high-speed CW (25 WPM+). My buddy Vlado (N3CZ) put the CTX-10 through some high speed tests, and was pleased with the results overall.
I will reiterate here that the CTX-10 lacks other controls many CW operators appreciate. Currently, the CTX-10 lacks a sidetone control; as a result, you cannot change the sidetone volume/tone, nor can you turn it off. I continue to hope that CommRadio will fix this quirk via a future firmware upgrade.
The CTX-10’s built-in CW keyer does not currently support iambic keying. Meaning, when both levers of a dual paddle are closed simultaneously (squeezed), it will not send a series of alternating dots and dashes. I imagine this could be addressed in a future firmware update.
Additionally, without re-wiring your paddle, you can’t change which side of your paddle sends ‘dits’ and which sends ‘dahs.’ A minor con, for sure–still, most modern QRP transceivers allow you this flexibility.
All in all, the CTX-10 will serve the CW operator much like a military set in field operations. True, I wish it had a few more adjustments, but it has all of the basics, and I’ve received several great reports regarding signal and tone.
Revisiting the basic feature set
Let’s be clear: as I stated at length in my initial review, the CommRadio CTX-10 was designed around simple operation, like one might expect from a military or commercial channelized radio. I know ham radio operators and preparedness enthusiasts who prefer this approach to gear design, and they will appreciate this CTX-10 design philosophy.
Still, the CTX-10 lacks many of the features and adjustments you’d typically find on a QRP transceiver in its price class. Instead, the CTX-10 was designed to handle many of these adjustments automatically.
The CTX-10 still has no separate RF gain control. The CTX-10’s RF gain is directly tied to the three AGC settings (slow, medium, and fast). While I believe it does a fine job of adjusting RF gain, I do ride an RF gain control a lot during noisy summer conditions, and miss this feature.
The CTX-10 still has no passband (PBT) control, notch filter, or noise blanker––all features I’d normally expect in a QRP radio at this price level.
There are no CW (os SSB) memory keyers. I wouldn’t expect these, as I believe only the Elecraft KX2 and KX3 sport this feature in this price class of QRP radios.
Please note: some of these features could potentially be added in future firmware upgrades. If one of these items is keeping you from purchasing the CTX-10, please contact CommRadio and inquire.
Is the CTX-10 for you?
With the most recent upgrades, CommRadio has solved the major issues that kept me from heartily recommending it in my initial review.
The addition of split operation was especially key for me, as I do operate split. The more nuanced adjustments to the CW keyer, an extra feature to prevent the radio from accidentally turning on while in transit, and the adjustments to the mic algorithm, all make this radio more pleasant to operate at home or (especially) in the field.
As I mentioned in the initial review, the CTX-10 owner is one who values a very simple, straightforward radio. Perhaps someone who began operating in a commercial, military, or aviation field, and/or who likes the “get on and get the job done” approach. Someone more interested in making contacts than in radio operations and refinements. Those who want a sturdy, lasting, no-frills, set-it-and-forget-it rig. If that’s you, take a closer look at the CTX-10: it may just suit your needs to a T.
If, however, you’re looking for a full-featured QRP radio with many of the features and nuanced adjustments you’d expect in the shack, check out the Yaesu FT-818, Elecraft KX2, or Elecraft KX3. All of these excellent rigs are time-tested and very flexible.
The two major advantages of the CTX-10 over competitors are:
the ability to charge the internal batteries from almost any voltage source, and
a higher TX duty cycle (without needing to add external heat sinks).
I believe the CTX-10 will have strong appeal for radio enthusiasts who value these characteristics:
All-in-one-box portability with no extra wired accessory components
Best-in-class internal battery life
Best-in-class intelligent battery charging
Digital modes like FT-8 and the ability to operate them in the field from internal batteries for extended periods of time
The equivalent of a simple portable military/commercial set
A well-balanced receiver with few manual adjustments
Broadcast listening, as the CTX-10 is also superb broadcast receiver
The CTX-10’s overall construction and components are, as I’ve said, near mil-spec. While the CTX-10 isn’t weatherized or waterproof––no more than any of its current competitors––the construction is top-shelf, for sure. It should run for decades without need of repair.
The CTX-10 is built like a tank, and has excellent receiver characteristics for field operation. It’s also designed and manufactured right here in the USA. All the better.
Since I plan for this article to be a regularly updated, I struggled to decide whether to keep it here on QRPer.com or on the SWLing Post–I certainly didn’t want two copies and I didn’t want to separate the hobbies with two different posts. In the end, since I’m now the shortwave radio columnist for The Spectrum Monitor magazine, I decided the SWLing Post would be the best place to hold the post.
I plan to update this app list regularly to include new apps and remove ones which are no longer available. If you have a favorite radio app that isn’t listed, please comment on the SWLing Post. Click here to read the article!
Many of you know that I’m not only into QRP, but I’m an avid shortwave radio listener, as well.
If you’re an SWLer, too, you might might consider venturing over to my shortwave radio blog, The SWLing Post, where I just published a review of the Elecraft KX3. Unlike other reviews of the KX3, this was originally written for the May 2013 issue of Monitoring Times Magazine and focuses on the KX3 as a shortwave radio receiver.