Many thanks to Curt (WU3U) who recently contacted me and mentioned he had built an IC-705 control interface for his Elecraft T1 ATU. This is a homebrew project based on others’ work and uses the FT-817 control port on the side of the T1 tuner.
I asked Curt if he could share a little more about his tuner to post here on QRPer:
Hi Thomas, I can’t take credit for the interface, as a guy in Japan designed it. When I built mine the entire instructions and notes for code for the PIC controller were in Japanese. I used Google translate to translate all of the information and I was able to successfully program the PIC chip and build the circuit. He has since released the details and code in English.
There are two designs: one with an on/off switch, and a newer version without an on/off switch that has auto power save. Both circuits are the same but the software for the PIC chip is different. If you build the one without the on/off switch there is a very specific sequence of connecting and disconnecting the device and it’s my opinion that the one with the on/off switch is the version that makes more sense to build. It shouldn’t matter which order you connect everything up and you simply throw the on/off switch to turn the device on and off.
Building the interface takes an understanding of a fairly simple electronic schematic and acquiring the parts. You also have to have a PIC programmer and the software to write his .hex file into the PIC controller chip.
The parts for the interface are all very common parts. The resistors are standard values. My build cost me about $30 in parts but I had to buy many of them in bulk from Amazon like the enclosures, switches and 3.5mm jacks and circuit boards to name a few. Individually the parts were $30 but my bulk order cost me much more. I also had to buy a PIC programmer for $25 and figure out what software I needed to download to program the PIC chip with the author’s code. It takes an experienced builder about two hours to build the device but it’s not out of the realm of a semi-novice as long as they can get the PIC chip programmed.
Here is his newer version with the same circuit design eliminating the on/off switch by using a different PIC program allowing the interface to have auto power shutdown (low power standby) but there is a specific order for connecting and disconnecting the interface. With this version there is still drain on the battery but the designer thinks that drain is less than the normal self discharge of the battery. I feel that any discharge combined with the self discharge of the battery will be more discharge than using the design with the on/off switch. https://amateur-radio.cocolog-nifty.com/blog/2020/11/post-591d17.html
I think this is a brilliant project and certainly one worth considering for those of us who already own an Elecraft T1 ATU and would like full control from the IC-705.
It was blustery and cold Monday morning due to a front that moved through during the night, so it was no surprise that the picnic area was completely void of (sane) people.
I found a picnic table on the bank that was relatively sheltered from some of the stronger gusts moving across the river. It was still quite windy, though, so I propped the MPAS Lite field pack on the table to provide a bit of a wind break for my log book.
Setup was quick. I don’t think I needed more than 4-5 minutes to have the CHA MPAS Lite deployed. This is one of the advantages of field portable verticals. The disadvantage? Verticals aren’t the most effective antennas in this part of North Carolina where ground conductivity is so poor. Still…I knew I could at least grab my ten needed contacts to have a valid POTA activation.
On the air
I won’t lie: it was slow-going.
For one thing, it was 11:00 local on a Monday morning–not exactly a prime time for a park activation.
I first tried making some SSB contacts on 40 meters and spotted myself on the POTA network. I managed to log 5 hunters in 30 minutes. With patience and time, no doubt, I could log ten SSB contacts, but I didn’t have time to wait, so I moved over to CW.
Oddly, the higher HF bands were in better shape than 40 meters that morning. One of my first contacts was NL7V in Alaska on 20 meters. A most impressive contact with 10 watts into a vertical.
I was on the air a full hour and did manage to log a total of 10 contacts. I’m certain if I would have deployed a wire antenna I would have had even better luck. Indeed, had I thought about it in advance, I could have actually deployed the MPAS Lite as a random wire antenna. (Doh!) That’s one of the great things about this antenna system is that it can be configured so many different ways. Next time…
Still…I thoroughly enjoyed my time at Lake James State Park. I’ll make this detour again in the near future.
The Icom IC-705 continues to prove its worth as a superb little POTA transceiver!
Since I had already set up my phone to record the video above, I decided to make a couple more.
I thought there might be some value in making real-time videos showing what it’s like operating CW and SSB during a POTA activation. The videos have no edits and haven’t been trimmed. It’s as if the viewer were there at the activation sitting next to me at the picnic table.
Operating CW with the IC-705
After setting up my station, I first started on the 40M band in CW. I meant to start the camera rolling during tune-up, but forgot to hit record. The video begins after I’d made a few CW contacts, but shows what it’s like changing bands and relying on the Reverse Beacon Network (RBN) to pick me up then the POTA website to auto spot me.
My video cut off abruptly due to a low battery message. I had to give my iPhone a quick power charge to make the next video.
Operating SSB with the IC-705
After operating CW for a while, I plugged in the hand mic that ships with the IC-705 for a little SSB action. My main goal with this video was to show how I call CQ and use the voice keyer memories in order to manage the field “work flow” process. I also speak to how important it is to either self-spot or have a friend spot you to the POTA network while operating phone.
I spent so much time setting up and running the camera, I wasn’t actually on the air for very long, but I easily managed to achieve a valid activation and had a lot of fun in the process.
I’m not a pro “YouTuber” as I say in one of my videos. I much prefer blogging my experiences rather than “vlogging,” I suppose.
Still, I think I’ll do a few more “real-time” videos of POTA activations and speak to the various techniques I use to activate parks. Since these videos aren’t edited for time, they may not appeal to the seasoned POTA activator or QRPer–that’s okay, though. My goal is primarily to assist first-time POTA activators.
Have you been activating Parks or Summits lately? Do you have any advice or suggestions I failed to mention? Or do you have suggestions for future topics? Please comment!
On Wednesday, October, 14 2020, the weather was gorgeous so I decided to make an impromptu POTA activation of Pisgah National Forest and the Pisgah Game Land (K-4510 and K-6937). These sites are the closest to my QTH and only a 15 minute drive (in fact, I can even hike up to the same trail network from my back yard).
My canine companion, Hazel, jumped into the car before I could even invite her to come along.
We drove to the trailhead, parked, and hiked a short distance into one of my favorite spots where it’s relatively flat, with lots of tall trees and almost no foot traffic from other hikers.
This activation gave me an opportunity to use the Icom IC-705 in more of a “backpack” setting since I hiked in with only my pack, Hazel, and my folding three-leg stool. Up to this point, I’d only used the IC-705 on picnic tables and flat surfaces since it can’t easily fit on my clip board like my MTR-3B, KX2, and KX1 can.
The activation also gave me a chance to evaluate a new product sent to me by the CW Morse company: their “Pocket Paddle” designed specifically for portable operations.
I decided to set up the Icom IC-705 much like I did the lab599 Discover TX-500 when I took it on hikes: mount the radio above the front pocket of my Red Oxx C-Ruck backpack.
The arrangement works quite well–I simply sit on the stool in front of the pack and hold my simple logging notepad and paddles on a clipboard.
While this particular site is great because it’s so accessible to me, the negative is it’s deep down in a valley surrounded by high ridge lines. I feel like this does have some impact on how well my signal travels.
Wednesday, it took nearly 50 minutes to rack up a total of 12 contacts in CW mode. I never bothered with SSB/phone because this site had no cell phone service and, thus, there was no way to spot myself on the POTA network.
That’s okay, I felt pretty chuffed about racking up 12 contacts with 5 watts and a wire! This is what field radio is all about, in my opinion.
After a little falling out with the mAT-705, I decided I wanted to try other ATUs with the IC-705. I used to own an Elecraft T1 ATU and loved it, but I eventually sold it for a song to a friend since all of my field rigs at that point had internal ATUs.
I reached out to Elecraft and they sent me a T1 on loan to give it a go. I’d forgotten how much I love this simple, effective ATU.
Even though the EFT-MTR is resonant on 40, 30, and 20 meters, moving to the 30 meter band requires lowering the antenna, pulling off an SMA cap on the coil, then re-hanging it. Not a big deal at all, really, but it’s so much easier to simply press the tune button on the T1 and have it match 30 meters without going through the normal process.
CW Morse Pocket Paddle
I also thoroughly enjoyed using the CW Morse “Pocket Paddles.” I’m not sure when they’ll be available to purchase (perhaps they are already?) but I can highly recommend them.
The paddle action is field-adjustable and even though there’s an Allen wrench built into the paddle base, the machined screws are easy to twist by hand.
They feel very sturdy, too, much like the other CW Morse paddles and keys I’ve used.
I believe the Pocket Paddles are going to permanently pack with my IC-705!
While visiting my parents this week in the Piedmont of North Carolina, I took some time Monday afternoon to take the new Icom IC-705 to field and activate Lake Norman State Park (K-2740) for the Parks On The Air (POTA) program.
So far, most of my time with the IC-705 has been in CW mode but a number of my readers have been asking about SSB operation and performance.
My goal for this park activation was to give the IC-705 a proper shake-out on SSB.
The activation was very much impromptu–I only decided I could fit it into my day an hour before my start time. In addition, while it wasn’t raining per se, there was a very heavy mist/fog that, at times, felt like a light sprinkle/drizzle.
I packed and planned on using my IC-705, mAT-705 external ATU, and Vibroplex End-Fedz EFT-MTR wire antenna.
I had an issue with the mAT-705 ATU (read more here), so opted for my trusty and incredibly capable Emtech ZM-2.
I did begin the activation in CW and quickly racked up a dozen or more contacts in short order after spotting myself. One of the great things about Lake Norman State Park is it’s one of the few locations I activate these days with proper cell phone coverage for mobile internet so that I can update my own activation spots on the POTA site.
I also moved up to 20 meters and switched over to my recently (re)acquired Elecraft KX1 (FYI, I named her “Ruby” so no way will I sell her again).
I quickly snagged two states (Iowa and Kansas) with 1 watt of power from the KX1’s internal AA cells, then 20 meters fell silent, so I moved to 30 meters to work a few more stations.
SSB on 40 meters
I then moved to the 40 meter band and decided to record a quick video after spotting myself on 7197 kHz. I wasn’t expecting such a productive mini pile-up.
As you can tell from the video, I had my hands full trying to hold my phone/camera, log, and manage the hand mic. Note, too, I prefer not hooking up the speaker portion of the microphone because audio from the IC-705 internal speaker is far superior:
I operated SSB for a good 30 or so minutes and was busy with contacts thanks to all of those excellent POTA hunters.
IC-705 Voice Memory Keyer
Before packing up, I remembered that my buddy Dave had asked me to make a video showing how I use the IC-705’s voice memory keyer, so I moved up to 20 meters (which you’ll see was pretty much dead) and recorded this.
Doh! I had the SSB position in LSB instead of USB! Thanks to one of my YouTube viewers who noticed this. I had been tinkering with mode settings earlier while evaluating the rig. No worries, though, this was more a demo of the memory keyer–check out SSB operation in the video above.
I was actually very relieved 20 meters was dead because I’m terrible at managing a camera, a tablet, and a microphone all at once!
The Icom IC-705 is an SSB champ
Despite the fact that I was using the default microphone settings and had not even touched the TX EQ or compression, I received no less than three unsolicited compliments about my audio during this activation. That is probably a personal record.
No doubt, the IC-705 is a very capable rig for QRP SSB where audio quality is essential.
On top of that, the eight voice keyer memories are incredibly useful when activating a park, a summit, or even running a contest where you could truly automate your exchanges.
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.
Icom Inc. will begin to ship the IC-705, a new all mode portable transceiver covering HF, VHF and UHF, for the Japan domestic market from the middle of June 2020. Shipments of the IC-705 for international markets will follow the release of the Japan domestic model. Timing of availability depends on the schedule of type approvals in each region. For the latest information about the availability in your country, please contact to your authorized dealer in your country. Icom Inc. is continuing to effect delivery of the IC-705 in the soonest time possible under the current circumstances caused by COVID-19. We thank you for your patience.