Category Archives: Videos

Field Report: Let’s build a super simple antenna on-site and activate this park!

Until 2016, I had never purchased a commercial field antenna; I built all the ones I had ever used.

These days, I take a number of commercial antennas to the field and use them in my real-time videos and I really enjoy deploying and using them. My buddy Eric (WD8RIF) reminded me, though, that I hadn’t actually used a homebrew antenna in ages. He was right!

You see, while I believe commercial field antennas can be incredibly durable and compact, it’s important to note that antennas are one of the easiest components of an amateur radio system to build yourself. They require only the most simple of tools and are very affordable. And the best part? They can perform as well as those that are available commercially.

I also get a great deal of pleasure out of building things.

A simple goal

I’ve mentioned in previous posts that I often set a little goal that runs in the back of my mind for each park or summit activation I make.

On Monday, June 14, 2021, I made a simple goal: buy my antenna wire en route to Lake James State Park, build the antenna on site, and complete a valid Parks On The Air (POTA) activation.

A very simple antenna

I also decided to employ my Xiegu X5105 since 1.) it’s one of the most affordable general coverage QRP transceivers I own and 2.) it has a built-in antenna tuner (ATU).

One of the cool things about having an ATU is that, if it has the matching range, you can allow it to do the “heavy lifting” in terms of matching impedance.

Although I’d never put the X5105 to the test, I suspected its internal ATU would have the matching range to forgo building a 4:1 or 9:1 transformer and simply pair it directly with a random wire.

All I would need was a 28.5 foot length of wire for a radiator, at least a 17 foot length for a counterpoise, and a BNC to binding post adapter.

The antenna would benefit from multiple 17′ counterpoises, but I really wanted to keep this setup dead simple to prove that anyone can build an effective field antenna with a very minimum amount of components.

Even though I have plenty of wire lying around the house to build this simple antenna, I wanted to pretend I had none to prove that any wire would work.

And to add just a wee bit more challenge, I also limited myself to shopping for antenna wire between my home and the park without making a serious detour from my route. That really limited my options because there isn’t much in terms of commercial areas between me and Lake James State Park.

The wire

As I left the QTH, I decided that the best spot to shop was a Walmart in Marion, NC. It would only be a four minute round-trip detour at most.  I had a hunch that Walmart would even have speaker wire which would be ideal for this application.

In my head, I imagined I would have at least three or four choices in speaker wire (various gauges and lengths), but turns out I had a difficult time finding some at Walmart. We live in such a Bluetooth world, I suppose there isn’t much demand for it these days. A store associate helped me find the only speaker wire they had which was basically a 100 foot roll of the “premium” stuff for $17 US.

While I would like to have paid a fraction of that, in the end it’s not a bad price because once you separate the two conductors, you have double the amount of wire: 200 feet.

Although the frugal guy in me cringed, I bit the bullet and purchased their speaker wire. To be clear, though, I could have found another source of wire in that Walmart, but I preferred speaker wire for this application. And $17 to (hopefully!) prove a point? That’s a deal! 🙂

Lake James State Park (K-2739)

Once I arrived on site, I found a picnic site I’d used before with some tall trees around it.

I cut 28.5 feet of the speaker wire and split the paired wires so that I’d have two full 28.5 foot lengths.

Next, I stripped the ends of the wire and attached banana jacks I found in my junk drawer. Although these aren’t necessary as the binding post adapter can pair directly with the wire, I though it might make for a cleaner install. In the end, though, I wasn’t pleased with the connection to the radiator, so dispensed with one of the banana jacks.

Next, I deployed the 28.5 radiator with my arborist throw line, and laid the other 28.5 half on the ground (the ground of this antenna would pair with the black binding post, the radiator with the red post).  I only needed 17 feet of counterpoise, but once it couples with the ground, I don’t think any extra length makes a difference (although less than 17 feet likely would).

The antenna was essentially set up as a vertical random wire with one counterpoise.

My new speaker wire antenna in all its glory.

Gear:

On The Air

I’ll admit: I was a bit nervous putting this antenna on the air. Although I felt the X5105 ATU *should* match this antenna, I had no idea if it actually would.

Fortunately? It did.

At this point, if you don’t want any spoilers, I suggest you watch my real-time, real-life, no-edit, no-ad, video of the entire activation (including buying and building the antenna!).

Click here to watch the video.

Otherwise, scroll for my activation summary…

I was very pleased that the X5105 found a match on the 40 meter band.

I started calling CQ in CW and validated my activation by logging 10 stations in 13 minutes.

Honestly: it doesn’t get much better than this.

I logged three more stations on 40 meters CW, then moved up to the 30 meter band where the X5105 easily found a match.

I worked one station on 30 meters before heading back down to the 40 meter band to do a little SSB. I logged three SSB stations in five minutes.

Mission accomplished!

In the end, I logged a total of 17 stations including a P2P with K4NYM.

Not bad at all for speaker wire!

After the activation, I tested the X5105 ATU by trying to find matches on other bands–I was able to find great matches from 60 meters to 6 meters. Most impressive!

X5105 battery

You might recall that I attempted to deplete my X5105 internal battery at my last (rather long) activation of Lake Norman State Park.  I wasn’t able to deplete the battery at that activation, but I finally did at this one.

All I can say is that I’m incredibly impressed with the X5105 internal battery.  This was my fourth activation from one initial charge on May 16.  The battery lasted for 20 minutes, taking me well beyond the 10 contacts needed to validate this park. I’ll now consider taking the X5105 on a multiple SOTA summit run!

Short Hike

Even thought the heat was intense and the humidity even more intense, I decided to take in a 2 mile hike post-activation. I snapped a few shots along the way.

This is the Christmas Fern which derives its name from a few characteristics: its resilience to early season snows maintaining a dark green color beyond Christmas, and because folks believe its leaves are shaped like Santa’s boots or even Santa on his sleigh.

Improvements

I’ll plan to add more counterpoises to the speaker wire antenna as I know this will only help efficiency.

In addition, I’ll plan to build even more antennas with this roll of speaker wire. If you have some suggestions, feel free to comment!

Thank you for reading this field report!

Cheers,

Thomas (K4SWL)


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2021 FDIM presentations now on YouTube!

Four Days In May is sponsored by the QRP ARCI

Many thanks to Pete (WB9FLW) who writes:

Hi Thomas,

This years virtual FDIM presentations are now available on-line for those who missed it.

Click here to view Part 1 on YouTube.

Click here to view Part 2 on YouTube.

Enjoy!

Thank you for sharing this, Pete! Sadly, I was unable to attend live due to my schedule, so am very happy to see these excellent presentations. I do hope that things will be normal next year and FDIM will happen in person again. If you attend the Hamvention, I strongly encourage you to also take in FDIM–it is always an amazing event.

New radio day! A shakeout activation on the Blue Ridge Parkway.

I learn a lot about a radio the first time I take it to the field. I’m not sure if it’s because being out of the shack helps me give it my full attention, or if it’s because field conditions vary and this allows me to see how flexible and adaptable the radio is.

On Monday (May 17, 2021), I was eager to hit the field with a new-to-me radio.

The previous week I didn’t log even one park or summit activation. Typically I’d hit at least two. There were a couple of reasons for this…

First, we had a fuel shortage in western NC and I didn’t want to burn any extra fuel for activations knowing we had some important family errands that week.

Secondly, I needed to hunker down and finish a number of projects I’d been working on including a lengthy two-part field radio kit feature for The Spectrum Monitor magazine, and a new in-depth TX-500 review for RadCom.  FYI: Part one of my feature for TSM will appear as the cover article in the June 2021 issue.

We also had a number of family projects to sort out. So a week at home perfectly timed with the fuel shortage.

The new radio

I collect reader and viewer suggestions and when I see that there’s a radio or product, in particular, folks would like to see tested, I try to obtain one.

One of the most requested radios lately has been the Xiegu X5105.

A number of readers have asked me to obtain an X5105 and take it to the field. Many are considering purchasing this (incredibly) affordable full-featured QRP transceiver, others own it, love it, and want to see how I like it compared with my other radios.

Last year, I came very close to purchasing the X5105 for review, but opted for the Xiegu G90 instead (here’s my review of the G90).

Even though the X5105 is only $550 US, I really didn’t want to make a purchase at this point because I’m budgeting for a new MacBook, new video camera, and I just purchased the TX-500.

So I reached out to Radioddity who is a sponsor over at the SWLing Post. I’d been in touch with Radioddity a lot as of late because I’ve been evaluating and testing the Xiegu GSOC for the past few months. They lent me the GSOC (and a G90 because I sold after my review) and I was in the process of packing up both units to send back to them.

I asked if they could lend me an X5105 for a few weeks. They were quite happy to do so and dispatched one in short order.

A clear relationship

Side story…

Back when I decided to place ads on the SWLing Post and QRPer.com, I worried about any inherent conflicts of interest. I read magazines that review products and can tell that they’re being gentle in their criticism because there’s a two page ad of the product immediately following the review. I don’t like that.

This conflict is something that’s almost inevitable with any radio publication that grows to the point of needing monetization to support it.

I made a few Golden Rules up front:

1.) I would only place radio-relevant ads on my sites. Period.

2.) My ads and sponsorships would be hand-picked and by invite only. I choose who can be a sponsor.

3.) I’m up-front with sponsors that my reviews call it like it is. If they send me product to review, I will give it an honest evaluation based on real-life use. If I don’t like it or can’t recommend one of their products, I’ll let my community know.

I’ve lost a couple of sponsors over Golden Rule #3 over the years. I’m okay with that because I’d rather not allow an advertiser on my site that can’t take customer criticism.

I invited Radioddity to be a sponsor of the SWLing Post last year after I had some positive interactions with them.

The Xiegu GSOC

Radioddity sent me the new GSOC to review in November 2020. I discovered in short order that the GSOC had some major issues and, frankly, I didn’t like it and certainly couldn’t recommend it. I communicated my concerns about this product with detailed notes and suggestions for improvement. I was open and honest about the GSOC on the SWLing Post (read the thread here).

Radioddity not only embraced my criticisms but sent them to the manufacturer and thanked me.

Impressive.

Blue Ridge Parkway (K-3378)

But back to the activation!

So on Monday, May 17, I had an errand in town that took me right past the Blue Ridge Parkway Folk Arts Center. The detour to do an activation was maybe two minutes, so there was no “fuel-shortage” guilt! 🙂

Also, I had a good hour to burn before I needed to go home and pack for a quick trip to visit my folks.

Equipment list:

I deployed the PackTenna 9:1 random wire antenna specifically because I wanted to see how easily the X5105’s internal ATU could match it.

I hopped on 40 meters first, hit the ATU button and it quickly found a 1:1 match–good sign!

This turned out to be a pretty easy and simple activation.

I started calling CQ and within 12 minutes I logged 11 stations.

I moved up to 20 meters knowing it would be a tougher band, but worked one more station–KG5OWB at K-0756–pretty quickly.

I was quite happy with  logging 12 stations in short order. A nice contrast to recent activations where conditions were so poor it’s been a struggle to get even 10 contacts within an hour.

I would have stayed on the air longer but (as I mention in the video) I wasted a good 20-25 minutes waiting on the landscape crew to finish mowing on/around the site before I set up my station. I didn’t want to be in their way.

Here’s my log sheet from the POTA website:

Video

Of course, I made one of my real-time, real-life videos of the entire activation. I’ve quite a long preamble in this one, so if you’re interested in skipping straight to the on-the-air time, go to 16:24.

X5105 initial thoughts?

So far, I like the X5105. It certainly accomplishes its goal of being an all-in-one “shack in a box.”

I performed this activation only using the X5105 internal battery. In addition, the ATU worked perfectly with the random wire antenna.

I like the size–it’s much smaller than I imagined. It’s also fairly lightweight.

It feels rugged, too–I wouldn’t be concerned about it getting easily damaged in the field.

The speaker works pretty well, but if the volume level is pushed too hard, it starts to splatter. I wish it could handle a little more volume before the splattering kicks in.

The ergonomics are pretty good. It didn’t take long to sort out how to use most of the functions.

One area for improvement? The owner’s manual. It’s poorly written and (frankly) reads as if it was rushed to print.

For example, I wanted to set up CW memory keying prior to hitting the field. Unfortunately, the owner’s manual was no help.

There’s actually a dedicated page regarding CW memory keying, but the first thing it does is reference a different section of the manual (without giving a page number). I followed the procedure, but it didn’t work. In fact, it didn’t make sense as it seemed lead me down the path of digital mode macros. I think the manual may be referencing a procedure before the last firmware update (which, it appears, changed the menu structure significantly).

If you can help guide me through setting up CW memory keying, please comment! I’m sure it’s a simple process, but I haven’t sorted it out yet.

Overall, though? I see why the X5105 is so popular. It appears to compete with a loaded Elecraft KX2. It’s a bit larger, heavier, and less “refined” but it’s also half the price of a loaded KX2.

I also think it’s a great radio for CW operators. The keying feels natural and responsive. It uses relays instead of pin diode switching, so QSK includes a little relay clicking. I don’t find it to be too loud, though.

I’ll be taking the X5105 out again very soon.  I’ve got it for 6 weeks, so it will get plenty of park and summit time. If you own the X5105, I’d love to hear your comments on this portable rig.

Thanks for reading!

Comparing the lab599 Discovery TX-500 with the Elecraft KX2

Since I took delivery of my lab599 Discovery TX-500, one of the most asked questions I’ve received from readers of QRPer.com and my YouTube channel is:

Which should I buy, Thomas? The KX2 or TX-500–?

I’ve also been asked which radio is “better” and which one I’d purchase if I could only buy one.

To address these questions, I decided to make a YouTube video where I outline some of the pros and cons of both radios, and compare them in terms of features especially with regard to field use.

Video

Click here to watch my video on YouTube, or use the embedded player below:

In this video, I mention a number of external sites. I’ve included them in the video description, but I’ll also link to them below:

Feel free to comment if you have any specific questions and I’ll do my best to address them!

Return of the lab599 Discovery TX-500!

Last year, I was lucky enough to obtain a lab599 Discovery TX-500 QRP transceiver for review on the SWLing Post.

It was a bittersweet experience because 1.) I really liked this transceiver, and 2.) I could only keep it for one week!

One week?!? (Now I can’t get this BNL song out of my head.)

Typically when I receive a loaner transceiver for review, I like to keep it a minimum of 4 weeks, but actually ask for up to 6 or 8 weeks. I like spending quite a lot of time with a new transceiver so I have an opportunity, for example, to take it on multiple field trips, pair it with a wide variety of antennas, and also using it in the shack.

My time was limited with the TX-500 last year because I had one of only a handful of pre-production units in the US (one was being used for FCC testing). Josh, from Ham Radio Crash Course, sent me the TX-500 after he spent a week with it, and I sent it Ham Radio Outlet where it would be eventually used as a demo unit.

When I took delivery of that TX-500 in late August 2020, I immediately hit the field. In one week, I performed seven park activations and also spent a great deal of time with the TX-500 in the shack.

For more details, click here to read my full review of the TX-500 on the SWLing Post.

In short, I really like the TX-500 as a field radio. Sadly, however, I didn’t have an option to purchase one anytime soon. There was already a massive backlog or orders at Ham Radio Outlet and lab599, like other manufacturers last year, experienced production delays due to Covid-19.

Last autumn, I asked lab599 if they would consider sending me another TX-500 on extended loan when they had a unit available.

Yesterday, I took delivery of a new TX-500!

Of course, I’ll be taking this unit to the field ASAP and plan to make a number of videos readers have requested comparing the TX-500 to the KX2, KX3, FT-818, and IC-705.

Although I’m not a fan of “unboxing videos,” I did make one of the TX-500 yesterday only moments after I took delivery. Why? Frankly, because I believe the box design itself speaks to lab599’s attention to detail.

I’ll admit right up-front that this video is a bit of an unrehearsed stream of consciousness ramble as I tried to share some of my thoughts about the TX-500. You’ve been warned:

Again, I’m looking forward to taking this weatherproof rig to summits and parks soon, so expect some field reports and videos featuring the TX-500.

In the meantime, please let me know if you have a TX-500 and consider sharing your thoughts and comments!

Which should you buy? The Icom IC-705 or the Elecraft KX2?

Without a doubt, the most popular type of question I receive from readers here on QPRer.com and over at the SWLing Post has to do with making equipment purchase decisions.

In the past two months, I’ve had numerous questions from QRPer readers asking my opinion about choosing between the new Icom IC-705, or the Elecraft KX2. In fact, as I started putting this post together this morning, I received yet another email from a reader asking my opinion about these two iconic QRP transceivers!

I love both of these radios for different reasons, so the answer is not an easy one.

Let’s discuss this in some detail…

I decided to make a video talking about the pros and cons of each transceiver and note the reasons why one might pick one over the other. My hope is that this will help inform a purchase decision:

Click here to view on YouTube.

Do you own both of these radios? Or did you recently decide to purchase one instead of the other? Please comment with your thoughts and opinions!

SOTA Field Report from Rocky Face (W4C/WP-006)

One of the things I love about POTA and now SOTA is that it gives me a reason to venture out and explore parks and other public lands that might have otherwise never shown up on my RADAR.

Rocky Face is a prime example.

On the morning of Wednesday, March 10, 2021, I would have never guessed that by noon I would be standing on the summit of Rocky Face. That morning, I had planned to activate the summit of Baker’s Mountain–a park and summit I know very well as I’ve hike the trails there almost monthly and the mountain is a stone’s throw from my parents’ home.

That morning, when I arrived at Baker’s Mountain Park and the gates were shut, I remembered that they are closed on Wednesdays.

Oops.

I was determined to hike to a summit, though, so I grabbed my iPhone and launched the SOTA Goat app, then searched for nearby summits.  That’s when I noticed Rocky Face which was *only* a 40 minute drive from Baker’s Mountain. I had heard of this 1 point summit and park, but had never been there, so why not take a little road trip and explore?

Rock Face (W4C/WP-006)

View of Rocky Face from the road.

It was a very pleasant drive which was made all the better by gorgeous sunny weather.

When I arrived on site, I was surprised to see just how well developed this park was. There were two different parking areas, a visitor’s center, picnic area, rock climbing face, playground, and numerous trails. There’s even a large area for outdoor events.

I took the “Vertical Mile Challenge” to the summit (which I would recommend) and was more of a workout that one might imagine for a 1 point 576 meter summit.

The trail was very well maintained. The ascent up the granite slope offered some welcome views of the surrounding area.

I was a little surprised to find some Nodding Trilliums blooming on the side of, and even on the path. A sure sign spring is on the way!

March 10th was also one of the warmest days of the year so far.

On the summit, there were actually a couple of picnic tables–a total surprise which made this SOTA operation feel somewhat luxurious!

On The Air

I set up the Elecraft KX2 and Chameleon MPAS 2.0 which were still packed from a SOTA activation two days earlier at Elk Knob (I’ll post a report of that activation in the near future).

I had not charged the Lithium Ion pack in the KX2 after the Elk Knob activation, but I assumed I’d still have enough “juice” to get me through the Rocky Face activation at 5 watts.

I started by calling CQ SOTA on 20 meters. A friend told me that propagation was very unstable, so I feared the worst. Fortunately, 20 meters was kicking (40 meters much less so).

Right off the bat, I worked stations in France, Germany, Slovenia, Quebec, Spain, and all of the west coast states of the US. It was so much fun and exactly why I love QRP and playing radio in the field.

As I switched from 20 meters to 40 meters, some hikers passed by. Turns out it was my cousin and her husband–what a surprise! Of course, they had no idea what I was up to, so I ended up explaining not only SOTA, but amateur radio and why I was using CW (yeah, I cut that bit from the activation video below).

They moved on and I hit 40 meters which was hit harder by the poor propagation. Many stations I regularly work were a good 2-3 S units lower in signal strength.

I am certainly looking forward to some stable propagation eventually! Still…very, very pleased with the 24 stations I worked and the QRP DX as well.

Here’s a QSOmap of my contacts–all from 5 watts and a vertical:

Video

Here’s a video of the entire activation:

Click here to view on YouTube.

Rocky Face turned out to be a fun little hike, productive activation, and a great opportunity to explore a new summit and park. I’ll certainly return!


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POTA Field Report: Pairing the Icom IC-705 with the CHA MPAS Lite at Tuttle

Last week, we had a glorious break in the weather–it felt almost spring-like.

On my way back home after visiting my parents, I decided I would take in a quick afternoon hike. I originally planned to go to one of my favorite county parks, but I also had a hankering to get on the air and that park wasn’t a part of the POTA network.

Tuttle Educational State Forest (K-4861)

I decided to stop by Tuttle Educational State Forest (K-4861) instead and make February 19, 2021 not only a hiking day, but a Parks On The Air day. Tuttle sports both excellent sites for POTA and a nice little trail system.

Gear:

I decided to play radio first then go on a hike, so I pulled out an antenna that I thought would give me quick deployment and pack-up: the CHA MPAS Lite.

I also remembered that a reader recently asked if I would include the deployment of the CHA MPAS Lite in one of my real-time, real-life activation videos. So I did just that!

Deployment was quick and the mAT-705 Plus ATU did a fine job finding matches on the CHA MPAS Lite.

I started calling CQ on 40 meters and worked quite a few stations in short order. When the first batch of eight chasers was worked, I moved up to the 20 meter band and started calling CQ. My hope was that I could work at least a couple of stations on 20 meters then pack up and go for a hike.

I started calling CQ on 20 meters and was quickly rewarded six additional contacts.

Without a doubt–if this wasn’t completely obvious in my video–the highlight was working my friend John Harper (AE5X) in Texas. I’ve known John for years now and have followed his excellent blog but we’ve never managed to catch each other on the air!

Turns out, John was using his recently unboxed Icom IC-705 as well. Click here to check out his post which includes a mention of this very activation. In addition, check out his thoughts after taking the IC-705 (all amped-up with the KPA-500) on the ARRL CW contest that weekend.

Another highlight was logging CU3BL in the Azores again. To me, it’s still mind blowing that 5 watts can reach out that far.  Here’s a QSOmap of the activation (click to enlarge):

In total, I logged 14 stations with 5 watts and a vertical in very short order, leaving me a full hour of hiking time! Mission accomplished!

Video

Here’s a real-time, real-life video of the entire activation:

The hike afterwards was just what the doctor ordered, too. I’ve mentioned before that my ankle has been healing nicely after twisting it badly in December. This hike was an easy one and gave me a chance to properly test my ankle before the (epic-to-me) SOTA activation I planned with my daughter, K4TLI the following week. (More on that in a future post!)

Here are a few photos from the Tuttle hike:

If you ever find yourself at Tuttle Educational State Forest doing a POTA activation, make time to take in a hike as well. It’s a gentle hike and even the long loop can be completed within an hour at a very leisurely pace.

Thanks for reading this field report and please comment with your experiences on the air and in the great outdoors!

Tom’s “Salt Water Amplifier” approach to portable & pedestrian QRP DX

Many thanks to Tom (G0SBW) who writes:

Hi Thomas

I thought I would drop you a line to say how much I am enjoying your posts – so much so I have subscribed.

I came across your posts while researching POTA (it is now available to hams in the UK and I have signed up for it). […]Most of my QRP sessions are pedestrian mobile but as I get older (I’m 82) I think they will become more /P.

What is quite different for me is that almost all of my operating is done from salt water marsh areas – so no trees at all for antenna supports. Of course, there are ways of getting around this problem by using masts with verticals, and mag loops. Using the readily available salt water amplifier, I’ve had quite a bit of DX success with SSB QRP. I’m now busy getting my CW up to scratch to get along better with POTA.

Here is a link to a YouTube video I made last year which shows a couple of my type of activity. It was made for a presentation so it is a bit long at 30 minutes:

73. ( or maybe that should be 72?). and Keep safe

Tom G0SBW

Thank you, Tom! Brilliant presentation! Thank you so much for sharing (although you’re making me homesick for the UK). I love the idea of the sea water amplifier effect and have employed that in the past to my advantage.  I wish the coast were a little closer to my QTH, but sadly it’s a good 4.5 hour drive at minimum.

Thank you and please let us know if you post new videos.

Click here to view Tom’s video on YouTube.

Testing the updated and upgraded Mat-Tuner mAT-705Plus portable IC-705 antenna tuner

On Wednesday (December 16, 2020) I took delivery of the new Mat-Tuner mAT-705Plus ATU.

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.

I received the original mAT-705 ATU via Mat-Tuner US distributor, Vibroplex, around the same time I received my Icom IC-705 in early October. I took the original mAT-705 to the field and made a quick video demonstrating its ability to find matches from 160 to 6 meters. In short, it did a brilliant job.

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.

Size comparison: mST-705Plus (left) Elecraft T1 (right)

 

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–?] 🙂


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