ELECRAFT KX3 & EMTECH ZM-2
- KX3 Transceiver HF/4M
- HandHeld 2M Transceiver
- SotaBeams 20/40 Linked Dipole
- Sotabeams BandSpringer Multiband
- Hawkins Vipers 2/4/6M
- Emtech ZM-2 Tuner
- 13.2V LifePO Battery
- Headphones
- Bits & Bats!
The ZM-2 is a Z-Match type tuning unit and is known by virtually every ham on the planet - whether they've seen one in person or in a magazine or on the internet. It's an American based company and the product is available in kit form or prebuilt. You can also opt for BNC or SO-239 connectors.
The only issue with buying a new ZM-2 (if you live in the UK) is the shipping costs - they're astronomical at the time of writing. That's the same for anything that you buy from the US unfortunately, so what starts out at £75 might end up costing you £125 😲 Makes you wonder how China can do it all for pennies! Someone's taking the pi$$. If you do order one, email them immediately after and ask them to give you some options - I'm sure they will!
If you ever see a used one for sale in the UK, grab it with both hands!!
So, onto the device. It weighs about 8oz and is about 130mm wide, 67mm deep, 40mm high. The outer case is made from a tough plastic and there are two large rotary dials for tuning around. You can connect an antenna using the BNC/UHF connectors or the binding posts. If you were using a ladder-line, it would plug directly into the red and black posts. If you were using say an EFHW, then you'd plug that directly into the red post. All very simple.
To improve the unit's ability to tune virtually anything, you can add further capacitance by using the toggle switch, providing an extra 250pF or 500pF (or leave it with zero additional capacitance).
The tuner will work from 80M thru to 10M and it will handle a maximum of 15W. That's fine by me, but I can already hear the 20W radio owners crying 😂 I must admit that I'm more than curious to know what you would need to do to improve the ZM-2's power handling. Could you replace the 2W resistors with 5W and use thicker gauge wire to wind the toroid? I strongly suspect that the actual tuning capacitors are the limiting factor. I dunno - maybe you do? Anyway, I would rarely use it at its 15W limit on SSB - if I was using DATA modes I'd definitely drop to 5W or less.
If you've never used a manual tuner before, don't worry - it's all very simple and easy to do. And the best thing about manual tuners is that you never have to remember to charge them or put fresh batteries in them - they don't need power other than the RF power of your transmitter.
The ZM-2 has a built-in SWR Bridge, controlled by a toggle-switch marked TUNE/OPERATE.
Broadly speaking, to operate the ZM-2 and get a good match, you simply follow these steps....
They cost a measly £20 and not only is it great value, but it also includes a handy little carry case (pouch). The TRRS to TRRS lead can be detached, which I really like.
I also like the fact that the tiny mic has two extra buttons for changing the radio's frequency, That's handy! Finally, it comes with a stick-on belt-clip which I personally won't be bothering with because it makes this little gem a bit bigger.
I ordered the mic and it was delivered very quickly and well packed. Inside was a note explaining how the microphone's performance can be tweaked to suit an individual's voice by altering the radio's setting - and Dave provides a link to a PDF file is included to show you exactly how to do this.
After plugging the mic into my KX3, I spun the dial and found EG7SDC on 15M. I only had some Duracell AA batteries inside the radio, so I tried making contact on SSB down at 4W through an EFHW. I was rewarded with a 59 and compliment on the audio. This was very encouraging considering that I had just plugged it in and played without any setup other than to turn MIC BIAS on.
After making a few more contacts on other bands, I decided to read the PDF that Dave had written and made some adjustments to the Compression and Mic Gain levels. This made the mic produce a more ‘punchy’ sound which is great for DX, but can be switched back when you want to transmit something easier on the ear.
I’m extremely pleased with this tiny mic. IMHO Elecraft should have produced something like this themselves instead of offering the MH3 (which I never liked). I look forward to using this mic much more in the future and it would be handy if Dave gave it a proper designation so people could find it easier, such as DP27G or DPKX3 or whatever.
Anyway, no matter what it’s called, it’s a little cracker and I highly recommend it!
73, Tom, M7MCQ
I love the idea of this minimalist CW paddle - it’s so tiny you can always find room for it no matter how small your field bag is! And it’s super cheap too. So I ordered the kit and it has sat on the shelf for months!! Why??? Here’s why…..
CW Paddle from VK3IL |
Yes, those SMD components are incredibly tiny 😳 😳😳 Boy, I knew before I ordered the kit that they were small, but it was only when I came to pick them up that I realised I just how awkward SMD work is for a novice. Even with a pair of tiny tweezers I struggled to pick them up and keep hold of them! They kept pinging out of the tweezer’s grip and very nearly got lost on more than one occasion.
Somehow, I managed to get them soldered onto the pads and although it’s not pretty 😂, it worked!
I plugged the paddle into a transceiver set to 20wpm and was delighted to discover that I didn’t miss a beat on my usual CQ CQ TEST DE M7MCQ string.
Very pleased with this little kit. Recommended for SOTA!
73, Tom, M7MCQ.
Okay, so after successfully building my QMX+ 😵 I connected it to a PC and ran the terminal-emulator PUTTY to run some tests. I haven't evaluated the outcome - for now it's just a case of running the tests and grabbing screenshots. They may be of use to other kit-builders.
AUDIO TESTS
ADC I/Q TEST (all bands similar)
The main area for concern is in the AUDIO TESTS where the separation between the two traces is not particularly good - especially on 20, 30 and 40M. Well, that's how I'm reading it anyway! Your comments are very welcome and so too are your recommendations for how to improve the readings.
The DIAGNOSTICS readouts don't ring any alarm bells with me and I'm quite pleased with the power-output on most bands. As for the rest of the figures, I'm not really sure what I'm looking for. Again, any helpful comments would be greatly appreciated.
The RF TESTS indicate (to me) that 20, 40 and 80M need some work. How to improve those readings - I have no idea.
I'm guessing that the first approach should maybe be to REFLOW all the solder joints on the toroids, followed by a redistribution of the windings and see what changes. Other than that, I'm at the mercy of you, the readers 😊🙏
UPDATE <<<<<
28 AUG 2024
For the tests above, I had used a cheap Dummy Load that I'd bought from a rally, and tonight I decided to try the tests again with a good quality Dummy Load. There was quite a big difference in the readings! So before you run your tests, make sure you are using a good DL with sound connections.
Having seen the new readouts, I feel quite happy with the results 😍
PLEASE LEAVE A COMMENT BELOW!
(Either anonymously or with your callsign)
Thanks!
73, Tom, M7MCQ.
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The first build of the QMX+ (HERE) ended up being a fail due to a short inside the CPU. Needless to say I didn’t make this diagnosis - it was a guy called Ian (G4GIR) who very kindly offered to examine the kit for me and he in turn received technical guidance from Jeff (W1NC) - I thank them both for their extremely helpful assistance.
As a result of Ian and Jeff’s help, I was able to convince Hans that the fault was not of my own making and so he sent over a replacement PCB and other components (but not the toroids). This meant that I had to reuse the old toroids, but rather than trying to desolder them all and then struggle to get them to fit with extremely short ‘legs’ (which would be nigh on impossible - it was tough enough originally), I decided to rewind them. Thankfully, I had two bobbins of the correct thickness enamelled wire.
The first problem though, was removing the hot-glue that I’d applied to the toroids on the original pcb! 🙄
Before I installed a single component onto the new pcb, I hooked it up to a PC with a USC-C lead and fed the pcb's Vdd with 3.3V (current-limited at 200mA) to make sure that the board showed up as an external drive - it did!
I wish I'd done this on my original kit because it would have showed that there was something wrong with the pcb because I wouldn't have wasted all that time and experienced all that frustration. It should be the first instruction in the build-manual.
Once I started the new build, it went together pretty quickly, although I will say again, it was a bitch to solder! I’ve never come across a pcb that’s given me as much trouble. It seems like the ground plane is huge and the solder pads are tiny.
Throughout the build I checked for a short between Vdd and Gnd. There were no issues this time and before I knew it, I was ready for the first power-up (again with a current-limited power supply set at 7V/200mA). The QMX showed up as a flash drive again on my PC so I dragged the firmware across to it and rebooted the radio. Bingo!….
With everything seeming to be working fine, I raised the voltage to 12V and tuned around for signals. I’m pleased to say that it seemed to be working okay, so then I tried some transmissions through my EFHW and searched the RBN to see how far I’d reached.
Once I could see that I was getting out well, I put the case together and tuned around the bands to test the CW Decoder - it was working really well!
So for now, I’m very happy! I’ve not done any proper testing of each band because I’ve had enough for now 😂 😂 I’ll do more tests next weekend and update this page.
When you make a warranty claim against a small company like this, you feel kinda bad about it and some people try to make you feel even worse, but when the claim is totally valid, I feel no guilt whatsoever and expect a very positive reaction from the supplier.
In the case of this build, the claim was appropriate and it was handled superbly by Hans Summers, without any delay or hesitation and I absolutely appreciate that. So much so that I went onto his donation page and made a voluntary contribution as a thank-you for making it easy.
UPDATE - TEST RESULTS<<<
Okay, so after successfully building my QMX+ 😵 I connected it to a PC and ran the terminal-emulator PUTTY to run some tests. I haven't evaluated the outcome - for now it's just a case of running the tests and grabbing screenshots. They may be of use to other kit-builders.
AUDIO TESTS
ADC I/Q TEST (all bands similar)
The main area for concern is in the AUDIO TESTS where the separation between the two traces is not particularly good - especially on 20, 30 and 40M. Well, that's how I'm reading it anyway! Your comments are very welcome and so too are your recommendations for how to improve the readings.
The DIAGNOSTICS readouts don't ring any alarm bells with me and I'm quite pleased with the power-output on most bands. As for the rest of the figures, I'm not really sure what I'm looking for. Again, any helpful comments would be greatly appreciated.
The RF TESTS indicate (to me) that 20, 40 and 80M need some work. How to improve those readings - I have no idea.
I'm guessing that the first approach should maybe be to REFLOW all the solder joints on the toroids, followed by a redistribution of the windings and see what changes. Other than that, I'm at the mercy of you, the readers 😊🙏
UPDATE <<<<<
28 AUG 2024
For the tests above, I had used a cheap Dummy Load that I'd bought from a rally, and tonight I decided to try the tests again with a good quality Dummy Load. There was quite a big difference in the readings! So before you run your tests, make sure you are using a good DL with sound connections.
Having seen the new readouts, I feel quite happy with the results 😍
The only thing remaining to do with this kit is to install the GPS unit, which I’ll do shortly.
PLEASE LEAVE A COMMENT BELOW!
(Either anonymously or with your callsign)
Thanks!
73, Tom, M7MCQ.
.
.
Last Easter I built a 5-band QMX and although I found it quite a challenge, it worked from the get-go and I was really pleased with myself! I get a lot of pleasure from building electronic kits and this will be the sixth one from QRP-Labs.
My only gripe about the QMX build was that the design left the components incredibly tightly crammed in, and I wondered why they hadn't made the PCB just 10mm wider. But since then, I have read Hans Summers' document explaining that, for him, it was a design-challenge to come up with such a compact design. Well, he did an amazing job!!
Anyway, here we are a year later and I see that Hans has released the QMX+ transceiver kit. This time, the design has much more space between components and I'm anticipating that the build will be far easier than the original design.
So what is a QMX+?? Well it's a high quality 12-band MultiMode (CW/DIGI) Transceiver which can be purchased as a self-build kit or as a pre-assembled unit - it's worth noting however that there is a very long waiting list for pre-assembled units - maybe up to 6 months 😮
In terms of functionality, the "PLUS" version is little different to the standard QMX but it has the advantages of being able to house a GPS unit, an SWR Bridge, a Real Time Clock (battery backed), a Developer's Kit and maybe even an ATU in the future. Hans also has other "secret" plans for the ongoing development of the QMX+ including SSB Mode which will be awesome!
I feel (and I may be completely wrong) that the QMX+ is a big step toward the release of the fabled QSX which will be an All Mode transceiver with who knows what features.
I currently own a couple of (tr)uSDX transceivers and these are simply amazing little radios which are multi-band, all-mode SDRs with built-in sound card, speaker, mic, keyer, PTT, etc. But their performance is far from perfect. Don't get me wrong - I love them - and when you're up on a hillside playing POTA or SOTA, their performance will bag you many contacts for little outlay. But they're just not in the same league as a QRP-Labs product.
I'll always remember when I built my first QRP-Labs kit - the QDX. It went together well and it performed superbly!! I was getting better results on my 5W QDX than my Multi-Watt IC-7300. I was (and continue to be) very impressed!
Sorry - I'm rambling. Let's look at the QMX+ Kit. It arrived in a single box which contained all the relevant components, each type being bagged separately. I'd also ordered the optional GPS Module plus (of course) the metal enclosure.
The quality of this kit is extremely high and I've yet to come across a QRP-Labs kit with missing pieces. The aluminium case is strong and well finished, with sharp text on the end plates.
The Assembly Manual for the QMX+ is extremely good (as usual) and I intend to follow the instructions to the letter, just as I've done before.In addition to having access to the manual electronically, I also decided to print a copy so that I could read through it prior to starting the build and highlight bits which I think warrant special attention, making notes in the margins of the page. I also use the printed manual to mark off each completed section.
I had decided to do this build at the weekend while I was at our caravan - nice and peaceful with no distractions. Prior to going there though, I wound all the toroids and then bagged them individually in tiny sealer-bags with ID labels.
All pretty straightforward but the most tedious was L506 |
Before starting the build, I laid out all the components and marked off the capacitor values. Once that was done, I fitted the caps, the diodes and the inductors. Very simple.
After that I installed the BS-170 transistors, clamping them in place before soldering.
You will soon notice that some of the solder-pads are TINY and it can be real difficult to get the tip of your soldering iron onto both the pad and the component at the same time. If you look at the adjacent image, you will see that some solder-pads are way, way smaller than others and some of the pads are barely visible. This is a multi-layer board and the ground really sucks the heat from your soldering iron, so make sure you use a decent one that can cope with it.
Diagram From The Manual |
I checked and double-checked the pcb for any obvious signs of faults such as dry joints, solder shorts, etc, but there was nothing obvious. I could see 9V at the power switch.
I sought help on the Groups.IO forum and got nowhere initially, so I submitted a trouble-ticket at QRP-Labs but six days later there was no response from that either.
It's extremely disappointing when stuff like this happens and I know there's bigger problems in the world, but neverthless I'm feeling quite disappointed considering that I've successfully built 5 other kits from Hans (including the regular QMX which is much tougher build) and a few from other kit manufacturers.
A few days on and members of Groups.IO started to make suggestions and I learned that there should be voltage at Vcc and Vdd but there was none on mine. The thread got busier and someone suggested that I try swapping out the Power Boards from my QMX to my QMX+. To reduce the risk of damaging anything, I was using a variable voltage/current PSU. With it, I could reduce voltage to maybe 7.5V and 200mA.
Before swapping out the boards, I recalled my soldering struggles and decided to reflow virtually all the connections to make sure that I'd not got a bad joint somewhere which was causing these issues. The Ground Plane on this pcb really does suck the life out of your soldering iron!
I decided to remove the power boards and the GPS module. It was then that I discovered I actually had a short on Vdd. No amount of probing with my DMM helped discover the source of the short, so I’ve given up for now.
I’ve approached an electronics professional friend to see if he can afford the time to do some fault-finding for me. If not, I might have to order another and start all over again 😪.
Part-2 to follow!
73, Tom, M7MCQ.
PART TWO of the build is >>> HERE <<<
This next post shows how I completed the kit and shows the final outcome 😊
There's so much hatred for FT8 and associated digital modes on social media that it becomes utterly boring!! I don't do a great deal digital work, but I'm sick to death of seeing people belittle other people's preferred mode of operation.
By far the biggest victim of this vitriol is FT8 and it pains me to see people tearing apart the enjoyment of fellow hams, claiming that FT8 will be the death of Amateur Radio, when the truth is, it has generated HUGE levels of interest and activity on all the bands, all the time and occupies a tiny amount of bandwidth and never encroaches on others.
Anyway, enough of all that - I am only posting this because I saw a little poem on social media that someone called Gregory Weisheipl posted and I kinda liked it...
FORBIDDEN FRUIT
In the quiet of the night, beneath the starlit sky,
A room is softly glowing where the radio waves fly.
Amateur radio’s magic in the dance of FT-8,
Where signals cross the oceans in a digital state.
No voices in the air, just pulses swift and bright,
As callsigns on the screen bring messages to light.
From distant lands they come, in bursts of code they greet,
In silent conversations, where strangers often meet.
With patience and with skill, they tune the frequency,
Each QSO a bridge, in this vast community.
From mountaintops to valleys, through the atmosphere they soar,
Connecting friends and strangers on a worldwide tour.
FT-8, a wondrous mode, with messages so brief,
Bringing joy and knowledge, in its quiet, coded speech.
Though words are few and fleeting, the bond is ever strong,
In every signal sent, we hear the same old song.
So here’s to every operator, with ears and hearts so keen,
Who find the joy in contact, in signals clear and clean.
Amateur radio’s charm, in FT-8’s embrace,
A timeless way of reaching out, across the human race.
PS : The poem was generated by ChatGPT! 😮
IC-705 THREE YEARS LATER
Three and a half years ownership of the ICOM IC-705 have passed and I thought it might be an idea to take another look at it to see if it still rules the roost for Portable Radios in 2024. In this 'look back', I'm only going to focus on what I've been doing and how well the 705 has worked for me. My original review is >>HERE<<
What should I compare it to? Well the truth is, there's nothing on the market to compare - that's a fact! Yaesu have dropped their old FT817/818 range and it was way out of date anyway. The Elecraft KX3 was a great alternative if you could live without all the features of the 705, but they're next to impossible to get hold of in the UK and the price has just gone plain silly anyway!
If you put the IC-705 and the KX3 side by side in a shack at home, you might be able to detect that the KX3 is slightly better at receiving really weak signals, but for the other 99% of the time, when you've driven, walked, hiked to the perfect take-off spot and set up your antennas, there's little practical difference between a KX3 and the 705. Or between a 705 and an 817. In fact, my $89 (tr)uSDX will probably get you as many QSO's in the log as the others from the top of a hill!
Over the last couple of years I've relied almost exclusively on my IC-705, using it outdoors, on hillsides, in the back garden, in a park, at the caravan, by the seaside and even at home as a base station. It's been utterly reliable and surprisingly tough even though it's not been wrapped in cotton wool. Unlike my Elecraft, I've never really worried about it - I guess I look upon it as a bit of a workhorse. If it gets a little scratch or a ding, it doesn't really matter. I don't believe it would substantially affect its resale price either.
The notable difference between the IC-705 and other radios is flexibility, features and what I call 'friendliness'....
The Icom IC-705 is more feature-rich than any other portable radio. It puts together such an awfully good package that you don't have to buy anything else (assuming that you use resonant antennas). You can operate throughout HF, 6M, 2M and 70cm on LSB, USB, CW, AM, FM, DV and DSTAR.
With the radios built-in server, you can operate remotely. With the built-in WiFi you can tether to your mobile phone and operate Digital Modes out in the field. Thanks to the built-in GPS, you can even ensure accurate timing for FT8, etc.