Icom uses this photo to demonstrate one of the ways the AH-705 ATU can be mounted for remote operation.
Many thanks to Bruce (W0MBT) who writes:
Hey Thomas,
After many years of inactivity, the combo of this blog, the IC-705, and Covid shutting down all the other fun things I like to do has finally got me somewhat active again. I agree with you that [the Icom AH-705] seems pretty large and expensive for a portable tuner, given the available alternatives. To me, the most interesting possible application is in a semi-permanent outdoor installation.
Currently, my setup is an EmTech ZM-2 installed in a watertight toolbox on my fifth floor balcony, grounded into the metal siding of my building, with a stealth radiating wire tossed onto a conveniently-located tree. It seems to get out pretty well, but QSYing across bands is a pain, and not really practical when it’s raining, which happens a lot in Seattle. I could replace that whole setup with an AH-705 stuck to the siding with double-sided tape.
My questions (and I realize you won’t yet have answers) are:
* How long will it run on AAs? This will determine whether I need to run 12V out to my balcony.
* What’s the maximum control cable run? In my current apartment layout, I’m looking at about 25′.
Bruce
W0MBT
Hi, Bruce,
First of all, I’m so glad to hear you’ve gotten back on the air and honored to hear this blog might have contributed to that a bit! Based on your current setup, it’s obvious that you’ll go out of your way to play radio. Anyone who’s willing to manually adjust a remote ATU each time they wish to hop around the band is dedicated to their radio play!
Since the AH-705 hasn’t been released yet at time of posting, I really know nothing about the AH-705 other than what I’ve read in the specs. I’m not sure how long a control cable could be nor how long AA batteries would last. We won’t know this until the AH-705 is tested.
If I were in your shoes, though, I wouldn’t wait on the AH-705.
I can think of at least two other options I consider to be better choices for a permanently-mounted remote antenna tuners:
1.) Assemble a remote tuner box
So at my QTH, like yours, I rely on an external, remotely controlled ATU. My shack is located on the first floor of my house. There’s a carport with a metal roof behind my shack. Since we designed and built this house. we installed conduit in the walls so that I could run cable from my shack to an antenna switching and tuning point mounted outside.
It’s built around an LDG Z11 Pro which is not marketed as a remote ATU. The Z11 Pro is mounted in a (rather ugly but effective) weather-proof box a friend gave me–I think the box was originally used in a remote sensing application. It actually has some penetration points on the side I was able to use.
In 2011, when I installed this ATU, I found an old sealed lead acid battery to power the Z11 Pro knowing the Z11 actually requires very little in terms of power. I had planned to bring the battery indoors and occasionally recharge it, but I also happened to have a 5 watt solar panel and Micro M+ charge controller, so I put them to use charging the remote ATU battery.
From inside my shack, I bypass all internal ATUs in my transceivers and only use my remote Z11 Pro.
The Z11 Pro is RF-Sensing, so as I move across the band, it automatically finds matches and keeps the SWR well within an acceptable range (I monitor it indoors with an SWR and Power meter, of course).
This entire system costs less than the $350 projected cost of the AH-705 and doesn’t require a control cable. The best part is it can be used with *any* radio and can handle 125 watts.
I used the Z11 Pro because I already owned it, but there are less expensive, smaller LDG tuners that could be used. You wouldn’t need to have solar charging as you could simply replace an external battery from time to time. These tuners are super efficient–so efficient, the sealed lead acid battery I installed in 2011 was nearly dead back then, yet it has provided enough voltage via my small PV panel to reliably power the Z11 Pro over 10 years of seasonal temperature swings.
But there’s still an easier and possibly cheaper solution.
2.) Buy a proper remote ATU
When I originally built my remote tuning system, there were really no affordable options commercially available. I believe SGC and Icom had remote tuners but they were very pricey.
The RT100 costs $250 US and is designed to be used outdoors permanently-mounted. You need no outdoor power source because the ATU is powered from a Bias T 12V source via the same coax cable between your transceiver and the ATU. Makes for a neat, tidy package outdoors.
Again, this ATU–unlike the AH-705–can handle up to 125 watts and work with any transceiver in your shack.
Indeed, I’ve been thinking about grabbing an RT100 for use with another outdoor antenna I plan to build!
Also check out the MFJ-926B for $330 US. If you’re like me, you may never operate north of 10-20 watts, but some may appreciate the 200 watt power handling of the MFJ.
Summary
To get back to your original question, I suppose what I’m trying to say here is the Icom AH-705 is a portable antenna tuner that can be put into service as a remote antenna tuner. It can do both jobs.
To me, though, it makes more sense to split these two applications: install a permanent remote ATU–that works with any transceiver–and also invest in a quality portable ATU for field work.
What are the major drawbacks of the AH-705 compared with a proper, dedicated remote ATU?
You’ll need to change AA batteries in the AH-705 on occasion or design a 12V source that can easily be recharged.
The AH-705 may (we don’t know yet) only work with the IC-705 and possibly similar Icom models. The LDG and MFJ ATU models above work with any radio.
The maximum power handling of the AH-705 is 10 watts–if you use other transceivers (if that is even possible) you’ll have to be extremely careful of your power settings, else fry the AH-705.
The AH-705 is pricey if the actual retail price ends up being near the projected $350 mark. Hopefully, it’ll be less than this.
The AH-705 will require a control cable. The options above are RF-sensing and do not.
My advice?
Build or buy a permanent remote tuner and hit the parks and summits with the ZM-2!
Since you already have the Emtech ZM-2, you’ve got a fabulous manual portable ATU. I use my ZM-2 in the field all the time (see photo above). Some folks prefer an automatic tuner for ease of use, but I’m guessing at this point, you’re an expert ZM-2 “tuner upper!”
Later, if you want to add an automatic portable ATU to your field kit, consider the Elecraft T1, the Icom AH-705, or an LDG model.
Readers, feel free to comment with your suggestions as well. I’m sure there are a number of options I haven’t considered!
Mat-Tuner sent this updated and upgraded version of the mAT-705 ATU to me at no cost and asked that I give it a thorough evaluation in the field.
History of the mAT-705
If you’ve been following the story of this tuner, it was the first introduced in September 2020 and designed to pair directly with the Icom IC-705 transceiver. Note that Icom plans to introduce their own IC-705 antenna tuner (the AH-705) but it is not yet on the market at time of posting, so the mAT-705 has certainly had a market opening.
The original mAT-705 had a mechanical power switch on the front/faceplate.
A couple weeks later, however, I discovered that the original mAT-705 had some design shortcomings. I updated my review with this follow-up post. In brief, the mAT-705 could deplete a 9V alkaline battery within a couple of days if you failed to turn off the tuner’s mechanical on/off switch.
Replacing the internal 9V battery was a complicated procedure requiring the user to carefully detach the front panel without losing the LED lenses that were prone to simply pop out. The 9V battery was mounted internally on the board with adhesive–obviously, not an ideal situation for an ATU that would require frequent battery replacement. Due to this, I simply could not recommend the original mAT-705–it was too pricey at $220 for an antenna tuner with so many design shortcomings. For full details, read this post.
Introducing the mAT-705Plus
Mat-Tuner was obviously listening to customer feedback, because within two months they introduced the upgraded and updated mAT-705Plus antenna tuner.
I love the USB-C charging port!
Here are the mAT-705 upgrades:
No mechanical on/off switch–power is internally managed
9V battery replaced with 1000 mAh internal lithium cells
Batteries are internally charged via USB-C port
No longer necessary to open the enclosure/housing
Update: Using the mAT-705Plus with other transceivers
Since the new mAT-705Plus lacks a power switch to manually turn it on, I originally noted that I was unsure if it could be engaged via RF sensing when paired with other transceivers. I tried to no avail. Before posting this review, I sent an inquiry to Mat-Tuner about this. Here is their reply:
The power of the new version of the mAT-705Plus tuner is controlled by the KEY signal of the control cable. When KEY is high, the tuner is automatically turned on. The function of following the transmitter to automatically turn on and off is realized.
In addition, the mAT-705Plus tuner follows the ICOM tuner protocol. Like other ICOM tuners, you can manually start the tuning cycle by manually customizing the control cable, just like the AT-120 tuner.
After you solve the KEY signal to trigger the tuner to start and make a manual control cable, you can use it [the mAT-705Plus] for other non-ICOM brand transmitters. But we do not recommend you to use it this way.
Because it is specially designed for the IC-705 transmitter, [it must be modified for use with] other transmitters, which many customers cannot do.
[Since] it uses a magnetic latching relay, after completing the tuning cycle, you can completely turn off the IC-705 transmitter power and connect the tuner to other transmitters.
The tuner will remain in the tuning state.
To clarify, I believe what the Mat-Tuner engineer meant is that if you tune an antenna with the IC-705, you can power the rig down, connect the mAT-705 to another transmitter and the mAT-705 will preserve the last tuner setting (the last match).
Let’s see the mAT-705Plus in action!
Yesterday, I took the mAT-705Plus to the field and paired it with my Chameleon Emcomm III Portable random wire antenna.
I made the following real-time no-edit video yesterday afternoon. Other than charging the mAT-705Plus batteries the night before, this video captures its first time being connected and used.
The Emcomm III Portable random wire antenna’s frequency range is 160-6 meters–the mAT-705Plus quickly found matches on every band.
Summary
At first blush, the mAT-705Plus looks like the ATU Mat-Tuner should have released on the first go: it’s portable, lightweight, fully automatic, rechargeable, and quickly finds matches across the HF spectrum.
We’ll see how well the power management works in real life. I plan to take it to the field over the next few months and carry a small USB battery pack to recharge the mAT-705Plus when the batteries are finally depleted. Hopefully, I won’t need to recharge it for a long time! The proof will be in the pudding!
Of course, I’ll also pair the mAT-705Plus with an assortment of antennas: random wires, verticals, delta loops, doublets, dipoles, and end-feds.
Stay tuned! [See what I did there? Rimshot anyone? Anyone–?] 🙂
A few weeks ago, I posted a report about doing my first park activation with the Elecraft AX1 super compact antenna. If anything, I felt the activation almost went *too* well using such a small antenna. I didn’t want to give others the impression this is all the antenna you’ll ever need–it’s just a brilliant compact antenna designed for convenience and accessibility. It’s a fun field companion and can be used pretty much anywhere.
Yesterday morning, I had a number of errands to run on the south side of Asheville and had not planned to do a POTA activation. While I was waiting on a curbside delivery, however, I was admiring the nice weather and thinking that I might venture out later in the day to do a Parks On The Air (POTA) activation. Part of me knew, though, that if I returned home, I’d get involved with projects and never make it back out to the field.
I always carry a transceiver and antenna in my car, so I opened the trunk and found my Elecraft KX2 transceiver field kit which included the Elecraft AX1 antenna. Technically, that’s a whole station! Why not give it a go–? I’m always up for a challenge.
Since I would be passing by the Blue Ridge Parkway on the way home, I quickly scheduled an activation on the POTA website via my phone so that the spotting system would know to grab my information from the Reverse Beacon Network (RBN) when I started calling CQ.
Blue Ridge Parkway (K-3378)
I knew this might not be an “easy” activation: I would be using a super compact field antenna that’s quite a compromise in terms of performance, propagation wasn’t exactly stellar, and I was activating a popular (hence somewhat stagnant) park on a Monday morning. Not necessarily ideal ingredients for a successful activation.
I also discovered my phone tripod in the trunk of the car, so decided to make one of my real-time, real-life, no edit videos of the entire successful or failed activation. (Hint: It turned out to be a success.)
If you’d like to accompany me on this park activation, check out my video on YouTube:
At the end of the day, the AX1 continues to impress me. It is a compromise? Yes. Does it perform as well as a resonant wire antenna? No. Can it activate a park as well as my other antennas? Yes.
AX1 QSO Map
Click to enlarge
No doubt, part of my success with the AX1 is because I’m primarily using CW instead of SSB to complete activations. I’ve made SSB contacts with the AX1, but I’ve never completed full park activations with it yet–in truth, though, I’ve never tried.
In fact, perhaps it’s just a lucky streak, but so far the AX1 has been as effective as many of my wire antennas in terms of simply completing valid park activations in less than an hour. My signal reports aren’t as strong as they would be with, say, my EFT-MTR resonant antenna or Emcomm III Portable random wire antenna, but it’s enough to get the job done.
If nothing else, I’ll admit that the AX1 reminds me of the magic of low-power radio each time I use it. When I log stations hundreds of miles away, with such a modest station, I feel like I’ve accomplished something.
In short? It’s fun to use.
Black Friday Sale
FYI: I just received Elecraft’s latest Black Friday 2020 ad and noticed that the AX1 antenna package (which doesn’t include the 40M extension) is on sale. Click here to check it out.
Not only will this antenna pair beautifully with my MTR-3B,KX1, and FT-817ND but I had completely forgotten I ordered it.
When I pulled the QRPGuys package from my post box, it was as if a little Christmas had arrived. I mean, is there a better feeling than getting a new kit in the mail–? I don’t think so.
Note: the following post was originally published on the SWLing Post.
Chameleon Antenna recently sent me a prototype of their latest antenna: the CHA MPAS Lite.
The MPAS Lite is a compact version of their MPAS 2.0 modular antenna system and designed to be even more portable.
Chameleon Antenna is a specialist antenna manufacturer that makes military-grade, field portable antennas that are low-profile and stealthy. Chameleon products are 100% made in the USA and their customers range from amateur radio operators to the armed forces.
Their antennas are not cheap, but they are a prime example when we talk about “you pay for what you get.” In all of my years of evaluating radio products, I’ve never seen better quality field antennas–they’re absolutely top-shelf.
Zeta
I’m currently in my hometown doing a little caregiving for my parents. I’d only planned to be here for a couple of days, but when I saw that the remnants of Hurricane Zeta would pass directly over us with tropical storm force winds and rain, I stuck around to help the folks out.
Zeta struck quite a blow, in fact. No injuries reported, but over 23,000 of us have been without power for over 34+ hours in Catawba county. With saturated grounds, the winds toppled a lot of trees and damaged power lines.
Yesterday, I wanted to take advantage of the power outage and get on the air. I couldn’t really do a POTA activation because I needed to manage things here at my parents’ house. Plus, why not profit from the grid being down and bathe in a noise-free RF space–?
I decided to set it up in their front yard.
CHA MPAS Lite
I had never deployed the MPAS Lite before, so I did a quick scan through the owner’s manual. Although the MPAS Lite (like the MPAS 2.0) can be configured a number of ways, I deployed it as a simple vertical antenna.
Assembly was simple:
Insert the stainless steel spike in the ground,
Attach the counterpoise wire (I unraveled about 25′) to the spike
Screw on the CHA Micro-Hybrid
Screw the 17′ telescoping whip onto the Hybrid-Micro
Extend the whip antenna fully
Connect the supplied coax (with in-line choke) to the Hybrid-Micro
Connect the antenna to the rig
Although I had the Icom IC-705 packed, I wanted to keep things simple by using the Elecraft KX2 I’d also packed since it has a built-in ATU.
Important: the CHA MPAS Lite requires an ATU to get a good match across the bands.
I wasn’t in the mood to ragchew yesterday, but I thought it might be fun to see how easily I could tune the MPAS Lite from 80 meters up.
I checked the Parks On The Air spots page and saw NK8O activating a park in Minnesota in CW:
He was working a bit of a pile-up, but after three calls, he worked me and reported a 559 signal report. Not bad at 5 watts!
I then moved to 40, 18, and 20 meter and called CQ a couple times to see if the Reverse Beacon Network (RBN) could spot me. I like using the RBN to give me a “quick and dirty” signal report. I was very pleased with the bands I tested:
Those dB numbers are quite good for an op running 5 watts into a vertical compromised antenna.
The KX2 very effortlessly got near 1:1 matches on every band I tested.
Of course, after working a few stations in CW and SSB, I tuned to the broadcast bands and enjoyed a little RFI-free SWLing. Noting 13dka’s recent article, I’m thinking on the coast, the MPAS Lite will make for a superb amateur radio and SWLing antenna.
Durability
Although the remnants of Zeta had effectively passed through the area three hours prior, it was still very blustery outside. I was concerned gusts might even be a little too strong for the 17′ whip, but I was wrong. The whip handled the wind gusts with ease and the spike held it in place with no problem.
One of the things I have to watch with my Wolf River Coils TIA vertical is the fact it’s prone to fall in windy conditions and many ops have noted that this can permanently damage the telescoping whip (the weak point in that system).
I’m pretty certain this wouldn’t happen with the Chameleon 17′ whip–it feels very substantial and solid.
Ready to hit the field with the CHA MPAS Lite!
I’m a huge fan of wire antennas because I believe they give me the most “bang-for-buck” in the field, but they’re not always practical to deploy. I like having a good self-supporting antenna option in my tool belt when there are no trees around or when parks don’t allow me to hang antennas in their trees.
I’ve got a park in mind that will make for a good test of the CHA MPAS Lite: it’s a remote game land with no real parking option. I’ll have to activate it on the roadside–an ideal application for the MPAS Lite.
UPDATE: Mat-Tuner released the latest updated and upgraded version of the mAT-705 in December 2020. It’s called the mAT-705Plus. Click here to read my initial review of the mAT-705Plus. Note that the following article pertains to the original mAT-705 which is no no longer being produced, but still available for sale (at time of posting) both new and used.
My initial assessment was very positive, but since then the shine has worn off. I’ll explain…
On Monday, I took the IC-705 and mAT-705 to the field for a little Parks On The Air (POTA) fun.
The Par EndFedz EFT-MTR triband (40/30/20M) antenna
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.
Issues
But if I’m being honest, my love affaire with the mAT-705 ended Monday due to a number of discoveries.
9 volt batteries
The mAT-705 next to the IC-705
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.
The LED illuminators
Once open, you discover that the 9V battery’s holder is a piece of double-sided tape. Seriously:
The mAT-705’s 9V battery holder
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!)
The Elecraft T1 ATU 9V battery compartment
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.
UPDATE: My review of the mAT-705 ATU below is accurate as of its original posting. Since this review, however, I’ve discovered some design issues that prevent me from continuing to recommend it. Click here for details.
UPDATE 2: Mat-Tuner released the latest updated and upgraded version of the mAT-705 in December 2020. It’s called the mAT-705Plus. Click here to read my initial review of the mAT-705Plus. Note that the following article pertains to the original mAT-705 which is no no longer being produced, but still available for sale (at time of posting) both new and used.
Last week, Vibroplex sent me their new Mat-Tuner mAT-705 external ATU on loan to evaluate with my recently acquired Icom IC-705.
The new mAT-705 antenna tuner is designed specifically for use with the new Icom IC-705 QRP transceiver. Connect the mAT-705 directly to the TUNER jack on the IC-705 with the included cable and control the antenna tuner directly from the front panel of the radio or use RF-sensing to actuate the tuner when changing bands. 1.8-54 MHz, 5-1500 ohms matching range, 16000 user memories recalling previous used settings internal to the tuner when returning to an earlier used frequency.
The tuner is 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.
Yesterday, I stopped by South Mountains State Game Land (K-6952) to give the mAT-705 some field time. Up to this point, I had not used the tuner other than tuning to the 80 and 40 meter bands from home (mainly to make sure it worked before hitting the field).
To really give the mAT-705 a workout, I deployed my CHA Emcomm III Portable random wire antenna. The Emcomm III is the only field antenna in my arsenal that covers 160 meters – 6 meters–an exceptionally wide frequency range.
What I like about this particular POTA site is the open parking area which allows me to configure the Emcomm III a number of ways.
The Emcomm III, being a wire antenna, is incredibly stealthy. Since you can’t see it in the photo above, I’ve marked up the configuration below (click to enlarge):
I’m guessing the apex of the antenna was easily 45′ high.
Activating
I started my activation on the 80 meter band.
After working a few stations on 80 meters, I decided to test the mAT-Tuner over a fairly wide frequency range before calling CQ on the 40 meter band.
Here’s a short video:
POTA Hunters: look for me on the 160 meter band this fall and winter! I’m so impressed how well it matched the Emcomm III on 160.
Indeed, I am very pleased with how quickly and efficiently the mAT-705 found matches on every band I tested.
In terms of form factor, the mAT-705 is quite compact, but a little longer in length than I had anticipated. Honestly, though, there’s nothing here to complain about.
The enclosure/chassis is incredibly strong. I’m willing to bet you could accidentally drive over it with your car and it would survive in tact.
The mAT is powered by an alkaline 9V battery. Vibroplex expects that this battery will last for months under normal use.
Note that there is a specific procedure for replacing the battery in order to protect the LED “illuminators” that are press-fit to the board.:
Remove the case by removing the 4 rear 2mm allen screws.
Turn the tuner upside down and shake it a little to get the PCB to slide out of the case enough to grab.
Carefully grasp the PCB sides and slide the board out slowly.
Update: I’ve followed the procedure above and still had an issue with the illuminators falling out. They really need to be secured better. I was able to re-insert them and close the ATU, but when you open the mAT-705 to change the battery, be in a space where you can capture both of them if they fall out.
Any mAT-705 negatives?
Not really, but I do feel the price is a little steep at $219.95–but then again the mAT-705 seems to do the job and do it well. I have to assume the TBA Icom AH-705 ATU will cost at least as much. I’m okay with paying at the top end of the market if I’m getting a quality product and this certainly seems like one.
I like the fact that the mAT-705 integrates perfectly with the IC-705 via the control cable and that I don’t have to worry about protecting it at all in my backpack. It’ll also take the IC-705 through the entire HF spectrum and even up to 6 meters.
I plan to continue using the mAT-705 for a while and even test it on severely non-resonant antennas just to see how far I can push it for a match.
Stay tuned! (See what I did there–?)
Many thanks to Vibroplex, again, for lending me this mAT-705 for review and evaluation.
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!
“Let’s go, daddy!”
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.
CHA Emcomm III antenna
Photo Source: Chameleon Antenna
I decided I’d pair the Emcomm III with the amazing Mission RGO One transceiver (a rig I’ll be reviewing in an upcoming issue of The Spectrum Monitor magazine).
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:
NVIS “V” configuration (lifted from the CHA Emcomm III Portable product page)
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.
Getting that first ten is a great feeling!
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.
Thank you, Chameleon Antenna, for sending me the Emcomm III Portable for a proper field evaluation. I’d also like to thank Chameleon Antenna for agreeing to be a sponsor of QRPer.com!
I know a number of participants in the Parks On The Air program who use the CHA MPAS antenna system–the MPAS Lite is the “little brother” of that antenna, according to Chameleon.
Although designed with the new Icom IC-705 and other QRP transceivers in mind, the CHA MPAS Lite can handle up to 100 watts in SSB or 50 watts in CW.
They plan to start shipping the antenna in early November 2020 and the price for the system is $340.00. That may sound like a lot of money for an antenna (it is, let’s face it!) but if you speak with pretty much anyone who owns a Chameleon antenna they’ll tell you it’s worth it. The quality is second to none. I’ve been testing their Emcomm III wire antenna recently and it must be one of the most robust portable wire antenna systems I’ve ever evaluated.
Also, all of their products are designed and manufactured in the USA.
We recently added Chameleon Antenna to our list of sponsors here at QRPer.com. I’m very proud to include them because one of my personal missions is to promote mom-and-pop companies that push innovation here in our radio world! It’s humbling that they support us too.
QRP radios, product announcements, reviews, news and more. Low power amateur radio fun!
Please support QRPer by adding us to your whitelist in your ad blocker. Ads are what helps us stay online. All of our ads are ham radio related--no junk, we promise! Thank you!
My advice?
