Was the problem resolved? 4S7EF

Several emails asking about the antenna mount. Here it is: amzn.to/3BufAjk

The voltage issue might be solved with a 12-volt buck-boost converter. Supplied with more than 12 volts it reduces it to 12. Supplied with less than 12 it boosts it to 12. The one I have maintained 12.5 volts as I adjusted the supply from 6 to 16 volts. They sell for about $25 on Amazon. One caveat. The switching of the supply is around 10KHz. I've only tested it with a voltmeter not my QCX+. I don't know if it generates RF noise or not.

Thanks for the measurements! I just finished building a qrp-labs QMX+. The first component level kit i have built in over 20 Years. Seems to work well. Thanks again!

I’m a KX2 fan. Enjoyed your video!

I like the motorcycle mount. 73

When you did this POTA activity did your FX-4CR have the internal Fan mod ?

Hello, on HF, at least up to 40 or up to 20 meters, it makes no sense to talk about receiver sensitivity: they all have more than enough sensitivity to receive natural noise and therefore useful signals, which must be higher in level than natural noise. Anyone can do a simple test by disconnecting the antenna from the receiver (it should be connected to a non-inductive resistor with a value equal to the input impedance of the receiver, but here it makes little difference). By turning up the volume, you hear a slight hiss; connecting the antenna, you receive signals but the noise increases a lot: with a more sensitive receiver, both noise and signals would only be stronger, but their ratio (signal-to-noise, which is what is needed for intelligibility) would remain the same. From about VHF and upwards, the discussion is reversed and the sensitivity of the receiver (with the same noise produced) becomes decisive for the reception of the lowest signals. 73s

FT-891 is with preamp on I guess.

I assume the FT-891 has a RF preamp running. Great performance from a kit, that's a fraction of the price of those others'. I wonder what the off frequency performance is like.

Thanks for the comparison. The availability of the narrow filters on the QMX really makes a difference in picking out really weak signals. Sometimes I go down to 150 Hz or below, play with the center frequency and the RIT and can pull something out that is not copyable on an of my small QRP rigs (KX1, MTR series, HB1B, etc.) That capability sets this rig apart from the others.

Super work, John!

Thanks for posting the test, John. I compared the FT-891 with the Penntek TR-35 using received signals from the antenna and they were quite similar in performance.

Meh, sensitivity is overrated (for HF). Dynamic range and receiver noise are so much more important for real-world operating, in my opinion. 🙂Thanks for the test though! 73s

Did you use any of the adjustment options available to you that could correct these issues? Your video does not show how you set the audio levels from the two tone generators, and a time domain view of the two tone signal would have been useful. We can't tell for certain from the video if the DUT is faulty or if the setup was faulty. The test itself as correct so long as all the variables are in spec. My concern is the ADC input is referenced to 1.1vdc and biased at half that, and that describes the audio signal input that can be processed. Each tone would have to not exceed half that when used together. The Class E amplifier does make it difficult to test the pre-amplified signal owing to the final stage flyback inductor's role in filling in the missing parts of the drive signal.

Great video! A+ . What paddle is that? And where did you get the flip feet? I got a handful of uses for those.

Tnx fr QSO John! 5:17 Worked you also on 12m that day (I use an inverted vee with a tuner on all the bands)

Nice DX! Thanks for taking us along. 73 de K4FR

How does your QMX+ compare to your QMX? I have QMX high and low band, and wondering whether the QMX+ is basically the two in one, plus 160 and 6. The 17' vertical worked great. I always wonder, what are hunters using on 12M. Tuning their 15M or 10M antenna on 12M, or really a resonant antenna on 12M? I often skip 12M because I assume not too many hunters have an antenna there, but after seeing your activation, I think I'll activate on 12M more often.

Impressive, John! Tell a little more about the antenna. I'm guessing a 17' whip. What counterpoise are you using with it? ... and how close are you to saltwater? FWIW, the little brother hi-band QMX is doing fine work for me. Satisfying tiny radios!

Great activation video

Amazing how Siglufjörður looks exactly like Grundarfjörður (:

Thanks for the demo! I saw your comment elsewhere about backing off the compression. Yeah, looking at your power meter on the KX2 it was staying almost full scale all the time which, I think, might indicate too much compression. That's consistent with the audio reports you received. Definitely a nice little mic!

A really nicely presented video John! I know you wouldn't discount using the buttons because they can reduce wear on the main encoder. That said I rewired a tiny Standard Communications microphone and getting the tiny buttons to work was just too much bother so I don't. That drone looks awesome! Along with a noticeable amount of other Elecraft peripherals, I just don't understand their pricing structure.

Fine business activation love the bike!

CQ CQ Pu5pqq forte 73 🇧🇷👍

I'm always reminded of just how beautiful my country is when I see stunning shots like this. Growing up here your used to it and tend to forget just how beautiful and stunning this island actually is.

Sweet. I am about to build a receiver & all my testers for L & C had crapped out when fired up. I do have a working Nano Vna & of course it came without any manual but I figured it could do the job but how. Now we know. Another guy read L directly but he did not share where in the vna's menu settings he was. This on the other hand is a simple indirect means to get what is needed. I even sent away for a $20 tester today. Well, it does not hurt having back up....

Very good review, thank you. I watched a different review on this spot welder and this guy didn't know anything about it!! I've had one for a while and like it a lot. Thank you for the video.

Sadly, these haven't been available on their website for some time now.

I don't hear thumps, but I don't hear the difference. I'm a new ham, and I'm new to CW, so I'm sure it's my inexperienced ear. I have one of those paddles - they are sweet.

Impressive scenery extremely well edited and that KX2 was certainly working for you. Just a great video.

What is that small green-faced device on top of your LDG tuner? What is it used for?

Do you have AGC enabled? Also, firmware version 19 came out recently and has an option to turn off thumping.

Great video John with fantastic scenery. Many thanks for the POTA park as well, pleased to have heard you! 73 de Jon G4IVV

Great scenery and fantastic views, and drone shots are spectacular ! I did about the same trip in 2016 following the Ringway 1 around the island....once in a lifetime experience ! Thanks for sharing John.....73 de ON4CDJ Patrick

Can this weld 2mm pure nickel strip..i have the awithz spot welder and it struggles with it

6:20 <-- THIS is gold to refresh our brains after a while

i own one of these, i got mine with software that did not support 11m but now its working, i just needed to find an older software version :) im now teærying to figure it all out for the CW, the beste BW and Filters.. i need the Decoder to work as good as it can. 73 from LA-M160560

Now I am even more excited to receive my QMX in the mail next week! I'm curious though why there's an option to turn off the thump suppression.

Does the input impedance of the meter on the audio leads matter?

Vector Net Work Analyser is the proper tool. Cost from 47€ to 259€ in a span from 100kHz at the low end and 900MHz for the cheap to over 4GHz for the more costly one. The measure bridge is built in and the dynamic range is up to 90dB. You can also do a lot more stuff with a VNWA

This bridge is useful up to 1500MHz, above that it is crap. The alternative is to use a VNWA, that 50€ up to 1000MHz, for 250€ up to 4GHz. With the VNWA you can do a ton more type of measurements and a lot more accurate.this is a toy

Sweet! Now to update mine! Thanks for the video, John. 72, John

I received my FX-4CR last week. I also purchased the cooling system. Prior to installing the cooling system the radio did get hot after about an hour on FT8. After installing the cooling system the radio ran much cooler. Still getting warm. Getting very warm after 4 hours of FT8 10w. I also plan on installing small heat sync on top. My Bluetooth window is installed on the bottom of my radio.

I'm surprised the Icom case "allowed" the Yaesu inside... You had a pileup from the git go, that's an awesome set up.

Neat video.....Nice Beam'er. Barry, KU3X

It's always interesting to hear your side of the QSO. I really dropped out there at the end. Great video, thanks for taking us along and being out there activating!

Great video. What's the link to the antenna? 😉

Looks like that antenna worked very well for you! Thanks for bringing us along! Now I am craving fish! 73, Patrick KF4LMZ