I have been paying close attention to the QMX Assembled Kits Status page for weeks now. On July 29th, i was 167th place in line. As of yesterday, i am in 33rd place in line. They've really been pumping assembled units out, and I'm anticipating getting an e-mail notice about mine any day now.
I've also been paying close attention to the QRP Labs iO group e-mail reflector and have been noticing that it's critical that the input voltage to the QMX does not exceed 12 Volts in order to not fry the finals. The problem is, of course, that any fully charged battery is going to have a voltage of 13.8 or 13.4 Volts on it. I know, that voltage is not under load, and will drop some as soon as you do put a load on it - but still, after waiting since April, I don't want to take any chances of frying this guy the first time I power it up. That would be just my luck!
So I ordered a 12V Voltage Regulator from DigiKey. This one is manufactured by SparkFun Electronics - I have a few of their kits and come to think of it, I didn't check to see if they have these in kit form - (I have since checked, they don't)
The cost was nominal - only $15.00 and since I don't have any LM7812's laying around, by the time I ordered the individual components and parts I would need to cobble something together of my own manufacture, with shipping costs it would probably exceed this. This little guy will bring any DC source as high as 36 Volts, down to a regulated 12 Volts.
Easy peasy, the input leads will get connected to alligator clips and the output leads will go to the required 2.1mm power plug needed by the QMX. I already ordered and received a few of these in the meantime. So I will be ready for some QMX fun if this arrives at my QTH in the next 2- 3 - 4 weeks. And conceivably, this will accompany me up to Alexandria Bay when Marianne and I head up there in late September, early October for our Anniversary. There are two state parks close by that can be POTA activations.
Fingers crossed!
Fingers crossed for Sunday, too. Both WeatherBug and WeatherUnderground are calling for cloudy skies with a 50% to 70% chance of showers and thunderstorms. Best case scenario might end up with me setting up in the backyard with the EFRW to the Jackite. Worst case scenario might mean operating from the shack. Well, heck ........ I never come close to the top, anyway, so I really shouldn't care as long as I get o participate.
Boo! Hiss!
To end this post, some photos from last night's NorthStar training:
One of my goals for 2024 was an electronics “Wildcard” where I would finish my QDX transceiver kit or some other ham related project. Today I will mark this one complete, as I finally got my QRPLabs QMX Multimode Transceiver on the air and completed a couple of FT8 contacts.
I did have a few glitches trying to get the rig on the air using WSJT-X (version 2.70 rc6). The first had to do with the short USB-C cable that came with the kit. When I tried using that, I received a pop-up message saying the USB device was unrecognized and had failed. Several folks said they had issues until they changed the USB cable, which I did, and that appeared to work just fine – COM 6 came alive.
The next issue had to do with setting the rig in WSJT-X. The manual suggested “TS-440”, which was a choice that appeared as “TS-440S”. However that did not work, and returned a pretty long failure message when I tried to the Test CAT function. The manual also suggested “TS-480”, which did appear as exactly that (no “S” at the end). That fixed the issues and WSJT-X was now in control of the QMX.
A few minutes later at 1842 UTC I responded to CQ POTA N0WHA EM91 who was -04, and received a -15 in return. At 18:48 UTC I responded to CQ POTA N4NR EM64, who was +04. I did receive a -14 report and a 73 in return. Both stations confirmed the contacts in their POTA Activator logs. So the QMX is working.
In the photo below, you can see the QMX attached to an Elecraft T1 QRP Antenna Tuner, and if you look closely you can see a 3dB attenuator installed in line with the QMX. The QMX lacks a tuner, and if it detects a high SWR, will immediately shut down the transmitter. This quick response prevents the T1 from being able to do its job. By inserting a 3dB attenuator, that guarantees no matter what the antenna load, the worst case SWR seen by the QMX is less than 3:1 – a value that no longer cuts out the transmitter. When the T1 is tuned correctly, the 3dB attenuator can be removed. If you leave it in, the 5 watt output of the QMX is reduced to 2.5 watts. 3dB of RX attenuation really doesn’t matter on the receive side.
In the photo below, you will see the exchanges with N4NR as well as the waterfall.
Many thanks to Karl (K5KHK) for sharing this guest post, which originally appeared on his blog, Karl Heinz Kremer’s Ramblings: A Digital Station in Your Pocket by Karl Heinz (K5KHK) How small can a complete station to work FT4/8 be? With the QRP-Labs QMX, we have a transceiver that certainly fits the bill for a … Continue reading Karl Heinz’s Pocket-Sized Digital HF Station→
This is a KM4CFT EFHW UNUN kit that I purchased via eBay. The circuit board is actually done, and I built mine as a EFRW UNUN, so that I can use the same wire for multiple bands. The only difference between the two versions is that the EFHW UNUN builds the toroid as a 49:1 transformer and uses a 100pF capacitor in the circuit. The EFRW UNUN builds the toroid as a 9:1 transformer and the capacitor is not used. I still have to measure out some wire - two lengths - one 41 Foot length (one of the non-resonant lengths recommended for 40 - 10 Meters ) for the radiator and one 17 foot length for the counterpoise.
When finished, it will be only a foot longer than my PAR ENDFEDZ, but will give me all bands, 40 - 10 Meters. The PAR will load up on 15 Meters with the KX3's auto-tuner, but 17 and 12 Meters are pretty much no-go.
This will be my antenna for Flight of the Bumblebees on Sunday, 7/28. If the weather is decent, I'll probably go to Cotton Street Park here in town and will shoot a line up into one of the really tall trees there and will use this as a hanging vertical or sloper. If the weather is crappy, I'll set up the Jackite in the backyard and will use this as a sloper while operating at our patio table under the cover of the big umbrella.
If it performs decently well for me, then I am counting on it and my ZM-2 tuner to pair up with the QMX when it finally gets here for a truly small portable operating package. I also ordered a 3.5 mm to 2.1 mm power cable adapter so I can use my little blue lithium battery with the QMX. Hopefully the QMX will be here in another month or two and I can take it with me when Marianne and I head up to Alexandria Bay for our anniversary in October. There are two state parks relatively close to where we will be staying that can be activated for POTA. Last year Marianne actually told me she wouldn't mind going with me if and when I activate them, when I brought up the possibility.
I'm quickly becoming enamored with operating portable with the smallest station that I can carry. It's truly amazing what you can accomplish with 5 Watts, if you know what you're doing and don't get into that nasty ol' mindset of "That will never work!".
On a side note ...... last year when we headed up to Alexandria Bay, we left on a Saturday after Marianne got home from work. Because we started out late, we spent Saturday night in Binghamton, NY. Recently, I looked up the hotel that we stayed at on Google maps and discovered that we were actually only a few blocks away from the street on which the original W2LJ lived! How cool is that? This year we plan to make the trip in one day, with no stop over. It's about a 6 hour ride up to Alex Bay from South Plainfield.
72 de Larry W2LJ
QRP - When you care to send the very least!
PS; Just checked the QRP Labs "Assembled Kits Order Status" page, which was updated today. I am 293rd on the list. If they build approximately 200 per month, then I'm looking at an arrival time of maybe late September. That would still be in time for me to take it along to Alex Bay. Fingers crossed!
by Matt (W6CSN) Bletchley Park Most readers of this blog are probably familiar with Bletchley Park and the significance of this place in breaking the codes used by the axis military forces during the second world war. The electromechanical systems developed and used here to aid the codebreakers in their daily work led directly to the electronic digital computers … Continue reading UK POTA Rain and Shine→
We’re excited to welcome Bryce Bookwalter (KD9YEY) as a guest contributor on QRPer.com! I had the pleasure of meeting Bryce at the 2024 Hamvention, where he shared his plans for an ambitious hiking adventure next year. Knowing he wanted to incorporate radio into his journey, I asked if he’d be willing to bring us along … Continue reading Guest Post: Preparing radio and trail gear for a once-in-a-lifetime, epic through-hike→
As I wait for mine, I enjoy the rig vicariously thanks to Hannes and (soon) others:One interesting comment on the QRPLabs group: "Once SSB is implemented in the QMX+, will that make it a QSX?"The QSX description (5 years ago) was for a 10-160m, all-mode rig so it seems like the 6-160m QMX+ may fit the description - if firmware-driven SSB is a possibility with these rigs. Like the QMX, the QMX+
The QMX+ 160 - 6 Meter QRP Transceiver. Even ordered pre-assembled, it comes to around a $200 dollar price point. Wow! A QRP CW rig with all bands for around two hundred bucks. Unbelievable!
On 1 May, Hans G0UPL released new firmware for the QMX.The primary goal of the update was to suppress the thump on CW that many users experienced on several bands.In my case, 80m was the most affected band.I'm happy to report that the new firmware does what it was written to do. Even before enabling the thump suppression feature, the new firmware seems to have fixed 80% of the thump generated
This morning, from Hans G0UPL:I am pleased to announce the availability of the 60-15m QMX version, which has been requested multiple times by POTA and SOTA operators. Note that there will be a few days' delay; the Rev 4 QMX boards will allegedly arrive here today according to the cargo company contracted locally by FedEx. But there will be some work to pack kits and program bootloader etc. I
Abbot and Costello were a favorite of my childhood, right up there with Laurel and Hardy. I always get a chuckle when I hear Lou Costello tell Bud Abbot, "I've been a baaaaaad boy!".
So what did W2LJ do that's so bad? Depends on your point of view. If you're a brother or sister Ham - nothing! To the uninitiated ..... "What do you need another radio for?"
I buckled under last night and ordered a QMX transceiver from QRP Labs. Not the kit, but a fully assembled-in-the-enclosure-80-to-20 Meter version. I've got too many kits in the pipeline that are waiting to be built. I don't need another. For that matter, I don't need another radio, either! But it's so tiny and can do so much and I've been wanting to get one for so long. I just couldn't sit on the fence any longer and last night I took the plunge. I figured I might as well order one while I'm still working full time. With retirement looming in the not too distant future, purchases like these might not be as easy to justify. I have no idea how long it will take to get here, but I'll wait. Oh, I know that it will be worth the wait! (Just looked at the waiting list - if I'm lucky maybe September or October).
So in that way, some would say that "I've been a baaaaaad boy!' To which I might reply, "It's a Ham Radio thing ....... you wouldn't understand!"
By the way ....... Happy Marcon's birthday! The ol' boy would be 150 years old today. Better than lifting a glass - get on the air in his honor today!
And I just stepped out of my office for a second or two to see that today is "Bring Your Kid to Work Day". It was exactly for this "day" back in 2005 that a bunch of us put on a presentation about Amateur Radio at the IEEE in Piscataway, NJ. Talking about "day" was my impetus for starting this blog - going on it's 20th year this year!
A recent get-together of Central Florida POTA ops, led, of course, by Bill N4NYM, allowed me the opportunity of meeting a dozen or so kindred spirits at Lake Louisa State Park where I very much enjoyed seeing their set-ups and eating their food.One of those in attendance was a newbie CW op, Glenn KO4NTA, and somehow Glenn and I got to talking about QRP. He had several rigs with him but the
A thread currently running on the QRP Labs group discusses the "thumping" issue on CW.I received my pre-built QMX yesterday and was able to hear for myself how this it sounds on the 5 bands, 20 to 80 meters. As noted on the group, the issue is more pronounced on 80 meters and is present to a smaller degree on higher bands, although 40m seems the least affected.The sound is the same whether using
Login
