Ham Radio (tr)uSDX vs QCX-mini. 3 Easy Tests to learn the truth about your radio.

Which Ham Radio QRP transceiver is better: (tr)uSDX or QCX-mini ? Both are popular choice among the QRP enthusiasts, so I decided to conduct 3 easy tests without a need of a stack of the lab equipment. The Silence, Pain and Purity Tests will tell you more about your radio than long reviews with unboxing and scrolling through the menus.
If you were about to buy one of these rigs, this video might be right for you! Please consider subscribing if you’d like to see more right-to-the-point ham radio videos!
Merry X’mas and the HNY! (even if you watch this in the summer!)
73! @Linas_LY2H
RF attenuators links (affiliate links, I earn small commissions at no cost for you if you buy through these links)
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[@hcy0]

Would be nice to see a comparision between (tr)uSDX and QMX since they use similar technology.

[@K6ARK]

Thank you Linas, I appreciate your creativity in coming up with simple and effective tests to compare the capabilities of each rig. I don't think the truSDX was ever intended to be a top performing transceiver, but more an experiment in what is possible with minimal hardware. Hardware. The capabilities that have been achieved in such a small package with such a simple architecture are pretty amazing. It is certainly usable, but not a top performer compared to bigger, more expensive, or in the case of the QCX mini, less capable in that it is mono banded and CW only. So, in that respect, I agree with Manuel that the comparison is a bit unfair, but still important to understand. If an operator wants a 5 band SSB and CW rig that fits in a pocket and costs under $100 US, there will be compromises. For many, they're worth accepting.

[@Linas_LY2H]

Thank you Adam, for your comment and opinion. Also thanks for an interesting YT channel which I enjoy to subscribe to! I really agree with your arguments concerning the hardware and capabilities of this radio. This actually were my motives to buy one ( actually, two :), and I never said this radio is good or bad because of my test findings, for “good” or “bad” is subjective , what is good for one , could be bad for someone else. I just did the tests and said this is noisy, this is quiet. You may choose either depending on your approach. If you like 5 bands for 100USD and don’t mind the hum and noise, I don’t care. I don’t work in the marketing department and has no intentions to sell either :). But I care about the informed choice. For me, Ham Radio is all about experimenting, not marketing. So I don’t buy the argument that it is unfair to compare radios because one is cheaper or more expensive than the other. It just does not matter. If I compare two radios on one band, in the same mode with all conditions equal and I get results for this one band, it’s irrelevant then, how many more bands, modes has the radio got, or what was the price of it, or what were the intentions of the constructor of the radio. I think it would be nothing unfair if I compared my K3 with the truSDX, on the contrary, it sounds interesting and tempting and educational! For this reason, I’m not interested in the “marketing department” arguments and debate as it leads to nowhere. I’m more in to the technical and experimental debate as it leads to discovering something interesting for me and, I hope, useful for those who watch my videos. Thanks again for your comment, Merry Christmas and the HNY! 73! Linas LY2H

[@K6ARK]

@@Linas_LY2H yes, agreed. I think many users do not understand the compromises of the truSDX. Your testing is very helpful for people to understand how the limitations of the radio might impact their operating. In many cases, the truSDX will be just fine, and is even capable of good DX contacts. But for those difficult contacts, it will suffer and might make the difference in a completed vs busted contact. I have three truSDX rigs and use them regularly. They are a blast, and a wonderful design. But when my goal is to work those most difficult contacts, I pick another rig.

[@-Todays-Tom-Sawyer-]

Howdy I was hoping for this exact comparison. I am just getting into qrp cw after years of boat-anchor AM & SSB rigs. I will buy both radios. KF6HF

[@dl2man]

Of course the QCX has the better receiver.... While the basic receiver concept is the same on both, QCX is monoband (more narrow), and single mode with a fixed narrow analog CW FIlter and there´s way more analog parts for the filtering in QCX, including infamous T1... I´m a fan of Hans work, and I also do love QCX receiver. We never said (tr)uSDX has a better receiver than the QCX. But (tr)uSDX is more versatile. And don´t forget: (tr)uSDX is doing EVERYTHING digitally. Try comparing performance on 80m. Go ! You can´t ? That´s right, because you´re limited to your 20m Setup on QCX. Background Noise can be controlled, when using the Digital (bandwidth) Filters and using AGC. By the way: If you disable AGC on (tr)uSDX, Volume also double acts as RX Gain. In order to do a fair comparison, you´d need to set the right RF/AF Gain Level. If you crank it all the way up, it will surely show more white noise. On SSB, we have even Noise Reduction algorithm. And of course it will act strange, when you´re putting in a 0,1mW Signal a few Khz next to the frequency you´re listening to. And that with RF/AF Gain cranked all the way up. Both signals are within the receivers Bandwith, and a 9+60dB Signal is not very realistic. That´s a big gun right next to your door. The scenario is absurd and not related to QRP/p practice. Reduce that to more realistic 9+20dB and the picture would be a different one. Especially with appropriate RF Gain Setting. On top of that, we have built in Attenuators up to -73dB to compensate in such a situation. The birdies are there. We don´t deny that. We´re trying to reduce them, but I´m not sure, if we´ll get rid of them. But in practice they are below the level of your athmospheric noise on the lower bands up to 20m. Try to do fair and realistic comparisons. If you select your test categories to match the border conditions of QCX, (tr)uSDX will always lose..... In practice you can do CW QSO´s with both, which was proven thousands of times. And on top: With (tr)uSDX you have 5 Bands, you can also do SSB QSO´s and Digimodes (including multitone modes, that not even QDX can do), which also has been proven thousands of times..... So what´s the point of your Video, I need to ask ? Compare it to an IC7300 or KX2 next time if you want to continue your methology. (tr)uSDX will look even worse in that case..... In a realistic scenario, it will work decent enough. 73 Manuel; DL2MAN

[@MrCudgel]

the point is that as a receiver (and transceiver) uSDX is complete shit!

[@Linas_LY2H]

Thanks for your long reply, Manuel! Opinion from the author himself is always very valuable for me. I don’t know if you watched the video till the place where I do “the Pain” test to your radio , but I have to stress that the offending signal was injected not a “few kHz to the frequency you are listening to” as you write, but ONE HUNDRED kHz away. I have not even come to injecting the offending signal FEW kHz away because I have stopped at 50 kHz away as the radio started going crazy. The QCX-mini at the same 100kHz was feeling absolutely nothing. Nothing much to add. Very nice that there is an attenuator built -in etc., but the purpose of the test was to compare the bare essence. And yes, S9+60 is not hat reare on the air, especially if in the field during the field day , also, the broadcasting stations can give that effect too , on 40m especially. I think, if you could improve the front end of the receiver, get away with this terrible hum and birdies, do something with this in-built speaker, the (tr)uSDX could become even more popular than it is now. I would probably buy my third one :), because I really like the multi-functionality, multi-bandedness and , most of all, the brilliant idea in itself of creating a really full SDR radio with so minimalistic and simple approach. And sure, I need more little rigs to apply my painful tests on! Zum Wohl! 73! Linas LY2H

[@dl2man]

@@Linas_LY2H The main thing to check would be the fact, that with deactivated AGC and fully cranked up Volume, the RF Gain was also fully up and beyond the point of what the ADCs can handle. If you really want to do a fair comparison, you´d need to calibrate the (tr)uSDX RF Gain Level so it matches the QCX. Then compare S/N Ratio. Set the IC7300 for example on 80m and activate Preamp Level 1 and 2, and you´ll see the same effect. Too much gain ! The QCX is fixed gain. 73 Manuel; DL2MAN

[@dewil23]

@@MrCudgel and how is that?

[@ryanv7075]

I think you miss one of the points of his video: for people who don't know as much about all of this and are trying to choose between the two. I'll use myself as an example. My first kit was the 4SQRP Cricket 40m. With my EFHW antenna, it is super sensitive to touch, and seems to need a ground. But also, when I got it to settle down on the crackle, it was so wide that it was hard for me to hone in on one station. It also picked up an AM station so loud that I couldn't hear the CW. It put me off of the radio and CW for almost a year. In contrast, my second kit was the Penntek TR-35. With that radio, there's no static/grounding issue on the EFHW, the filtering lets me hear just one station calling, and I have yet to hear an AM station. I have enjoyed using it to make my first HF contacts, which was what I was after from the start. For me, the fun minimalist design of the Cricket didn't carry a lot of weight, since I only had the one antenna at the time and very poor CW receive. Thus, videos like these can help newer operators with limited budgets know what they are stepping into. I look forward to revisiting the Cricket one day, and maybe playing around with adding filters, using a different antenna, etc. But for now, I'd rather spend my limited time improving my CW and making contacts. Hope this helps with perspective :)

[@randalltom9750]

Linas, you are my Elmer! I have watched your videos for some time now. Your advice & insights are invaluable, and I learn something new each time I view your videos. Thank you again my friend for this side-by-side comparison. I own both radios, and I love the QCX Mini. I now own the 20, 30 & 40 meter bands, and two QDX radios. They are brilliant, and Hans is a gift to our hobby. Thank you Linas, and thank you Hans!

[@Linas_LY2H]

And thank you Randal for your nice words and dedication for the hobby! 73! Linas LY2H

[@sanjithnair3266]

Great video. TNX 73

[@fotografm]

Excellent real world comparison of two rigs. Thank you for publishing this and saving me the time and effort !

[@jcalbano]

I enjoyed this video very much! A very nice, fair and accurate comparison..you did a great job...thanks for sharing this! 73 John N6TRC

[@ThomasK4SWL]

Thank you for sharing this, Linas. I think both of these radios are technological marvels. The (tr)uSDX accomplishes so much on such modest hardware. Ten years ago, even, I couldn't have imagined a radio that could do so much for such an affordable price and in such a compact form-factor. The QCX-Mini blows my mind, too. It's so compact and insanely affordable as a kit. True, it's monoband and CW only--so a more surgical market approach--but the performance rivals much pricier radios. It does one thing and does it well. At the end of the day, for me, I find the (tr)uSDX a lot of fun and fascinating, but I don't take it to the field for SOTA and POTA because it's not well suited to handle pileups when they happen. The receiver falls apart. It's noisy, too, and that interferes with any weak signal work like Summit-To-Summit contacts. The QCX-Mini can handle pile-ups much better and, in fact, has handled some of the biggest pileups I've experienced in the field. It's a joy to use. We're so lucky to live in a world with developers who can make these wee radios! My hat's off to them and I look forward to their future innovations! Have a Happy Christmas and Peaceful 2023, Linas! Keep up the great work! -Thomas (K4SWL)

[@Linas_LY2H]

Thanks Thomas! Merry Christmas and Happy New Year to you and your family! I agree with everything you said about these two radios! The SDR technology is just so fascinating by its simplicity and yet by the power of software. I'm following the microSDX project since the very beginning and I'm amazed by how creatively it's been developing during a year or two. For me, the uSDX and (tr)uSDX is the best educational project ever allowing to compare the technological development during years. The practical application, though, is a bit different thing, the radio performance is heavily dependant on many very specific engineering decisions. Anyway, I have two truSDX's, one QCX and 3 QDX - all because it's so much fun to study these little radios and play with them. And, surely, share the fun with others! 73! Have a nice weather for your activations! 73! Linas LY2H

[@WECB640]

This is one of the top 10 BEST ham related videos I've seen in 2022. Just magnificent! It shows that you don't need to quibble about all the intricate measurments one would do in a proper lab (ie Sherwood Engineering). Some basic tools and a few simple tests will unveil the weakness or strengths of any two receivers. Merry Christmas Linas. Bravo! Take a bow my friend.

[@Linas_LY2H]

Thank you very much OM! Merry Christmas and the HNY! 73! Linas LY2H

[@cyclicalobsessive]

Wow, Really perfect testing apropos to my dilemma. Got my ticket 50 years ago this year, and would like to brush up my fist, and return to the air without investing heavily to build a shack. I have been waffling between the (tr)uSDX and a QCX-mini almost hourly for weeks now (and even briefly considered a Pixie on 7.050). I know myself, if I have SSB available, the CW will suffer or never happen. SSB is just such a easy/fun mode to listen to and actually communicate with. Your video convinced me to keep listening using WebSDR, but get a QCX-mini to have the better receiver and keep my CW motivation alive. Additionally, your video answered my fears about buying an inexpensive toy that might put out illegal spurious signals - that was very comforting. Wishing you peace, soon.

[@Linas_LY2H]

Thanks for watching, I’m glad you found it useful! BTW, since this video, the QRP-Labs has got something more which might fit your needs, like QMX (5 band merger of QCX-mini and QDX in one package) and QMX+ (bigger size , 10-band merger of QCX and QDX), both doing CW and digital modes with SSB in the future software updates. I have no affilliation with the QRP-Labs, I just like buying things from them because of their low price and high quality. Good luck! Let us know what was your choice! 73! Linas LY2H

[@cyclicalobsessive]

@@Linas_LY2H 7 hours into building the QMX now. Phenomenal build manual and superb design with support and updates!

[@Linas_LY2H]

@@cyclicalobsessive Fantastic! I have the QMX up running since few months now. My biggest building lesson learned- get a powerfull soldering iron enough ( 60W or more) while soldering grounded contacts, especially the both encoders. QMX is doing great on FT8 and RTTY , and is getting better in CW with each firmware upgrade. Good luck in building! 73! Linas LY2H

[@samhoover5482]

Good video, my (tr)uSDX does the same thing. From what I've seen in your video, I'm glad I ordered the QCX-mini's. Thank you.

[@toybuns775]

Love my truSDX, never even heard of the QCX-mini.

[@Johnstage]

Wonderful review. Very useful. Thx!

[@ardilla8651]

Tnx Fer video, sir. I owned two QCX and built another two more and It IS a great value ratio between price and performance. The usdr is a simply proyect but nothing more.

[@clintonthomas6031]

Excellent video. Thank you for your time. I have a tr usdx which works well, and considering it cost 120 and to buy 5 mini's would be almost 400 with enclosures. I may look at the mini's again as my cw skill improves. Can't wait to try out some of the things you did, with my nanovna.

[@vk2ihl]

Dear LY2H, your video has proven it all, you must be very proud of your demonstration which may help potential buyers to make their decision. IMO, there is no point to buy a multipurpose knife when the blade is failed at the cheese test! (QSD is for quadrature sampling detector) TruSDX uses NM0S/WA0ITP LPF for front end receiver, with a cutoff frequency at 28MHz, on 20m band, which presents an amount of -99dBm of thermal noise and an insertion loss of 6dB due a to mismatch of 12/50Ω LPF to the 200Ω QSD input. The 28MHz bandwidth for a single ended QSD is prone to reciprocal mixing as you experienced with 100kHz test away from your reception frequency. The QXC has a narrow 1.5MHz bandwidth BPF with insertion loss of -1.75dB and -144dBm thermal noise and a double balanced sampler. Based on YoungBlood AC5OG SDR for the mass (QEX Mar/Apr 2003) the doubly balanced has a differential voltage gain of 6dB. Clearly the the receiver of QCX is far superior to the TruSDX… Wonder why DL2MAN does not have his capability to modify his stolen circuit from NM0S for a perfect impedance matching with his QSD.

[@Linas_LY2H]

Dear Pascal, thanks for this comment! It's just a brilliant and most professional explanation on how the front ends are arranged on both radios! Your comment is worth reading some more times with the schematic diagrams in front of me! I'm gonna have some more nice time! Merry Christmas and the HNY! 73! Linas LY2H

[@vk2ihl]

Related to v1 for “Classic” and “Hi Band” RF board, DL2MAN opted for 8Ω load. This matter will make a direct match to the QSD becomes worse, meaning more loss inducing to RX path. The option for 8Ω load demands better transistor than the BS170, which can provide 7W RF output, according to WA0ITP spreadsheet. I wish him luck to his stunning achievement, unfortunately low cost 28MHz Mosfets are in short supply with 70 weeks lead time!

[@rst5nn]

Linas, thank you for video. No doubt that QCX has lowest noise level comparing event with productions trancievers. Just add interesting point. You can install to your mobile phone application like Spectroid which perform FFT for sound from microphone. This also shows real picture of filters in RIGs. The biggest disadvantage of (tr)usdx personally for me, that during receiving CW it produces a lot of mirrors and phantoms station on the band with strong level. And in some cases during receiving QRP signal it is hard to understand is it real station or mirror of strong station 3kHz aside.

[@EA3QC]

Without going into judgements between both radios, I think that the backgroung purpose of this video for all of us, should be the simplicity of the equipment for make our own measurements in the Shack. It's very easy (and cheap) to get as we have seen. Thanks Linas for caring that we continue to be curious.

[@Linas_LY2H]

Straight to the point, thanks! 73! Linas LY2H

[@bryantwalley]

Hey man. Just found your channel. This is a great comparison. Can you share the link to the power supply you are using in this video? Or, I’d you have a video about it, a link to that would be great. Thanks .

[@Linas_LY2H]

Hey man. Thanks for watching, I'm very glad you find it useful! The power supply in this video is just a DIY Li-ion 12V 5Ah battery pack providing power for both radios in order to have equal conditions in power supply. The video on how I made it is here: kzbin.info/www/bejne/nJjOeGh7j9CffKMsi=jT3TFbWT_8moUsuD HTH, 73! Linas LY2H

[@alexanderkrau1440]

That is a really great video! I am amazed how you measure the most of all important receiver and transmitter HF parameters with low cost measurement equipment. But of course this is the right way for amateur radio and the comparison is more than just a subjective view. Due to the direct comparison it becomes objective. Of course the true sdx is able to operate multi band and multi mode. That can be a big advantage in the field. But my experience with the qcx mini is the same - it is a very fine CW TRX. I learned much due to your video, e.g. I didn't know that my nano VNA can be used as a CW freq. signal generator. Great 😁 By the way: I think the Venus SW-3B 3 band CW TRX is very good, too. I love to use it for SOTA activations and it has a very quite RX, too, but three bands. That's why I prefer it instead of the qcx mini. Maybe the SW-3B should be also compared in an HF test measurement. ;) Thank u vy much es 73 DL5AZZ

[@Linas_LY2H]

Thanks Alexander! I’m glad you found it useful! I don’t have the SW-3B, but I have the LNR precision MTR-3B - a bit different design but still quite similar to the SW-3B. I used to operate it a lot on trips around Europe - it’s a nice classical crystal filter design. TruSDX is a totally SDR schematics and is interesting because of that attempt to make digital processing of the signal on such a minimalistic processor as Atmega328P. Knowing this, some quality issues which I revieled in my video could be understood and forgiven :! QCX-mini is not fully SDR and it uses the same processor for different tasks not overloading it with the full scale signal processing. Have fun! 73! Linas LY2H

[@chrisherd991]

Hi Linus, thank you again for showing us all how to test radios in a simple way. The results point to two different radio configurations ie mono band (front end RF filtering and back end narrow audio filtering). The other unit demonstrating what is expected for a wide band RF and voice bandwidth audio. Are the “birdies” a problem or do they need some kind of fix?

[@Linas_LY2H]

Hi Chris, thanks for watching! It was not a “how to” video, so I’m not teaching anybody how to test their radios :), it’s just my personal experience and my personal opinion about the results. I’m not sure the results point to two different radio configurations in the sense of filtering. Yes, the truSDX is multiband but they are using filtering on each band as in the front end ( the transmitting LPF (acting also as partialy band -pass filter due to its class E specificity) is also used on receive ), as in the back end (there is a choice of digital narrow band CW filters in the processor). The QCX has the analogue filtering both in the front and in the back end. In no way, IMO, the difference in the filtering methods can be an obstacle to make a comparison between the two. On the contrary , the comparison only helps to see the differences in performance between the two while performing the same task under the same conditions (both rigs on 20m band, 200Hz CW mode, no AGC). As it comes to the birdies, well , probably nothing is a problem in ham radio, it’s more a question of fun. In actual reception the signals of stations on the air probably would overcome the signals of birdies anyway. But may be not. So I feel more fun when I know that my radio is clean and what I hear is really signals of the stations but not their phantoms on mirror channels etc. :). I’m not in the position of making professional comments about the nature of these birdies and the ways to kill them, but I’m sure there are people who could and had written many good articles already. Have fun! 73! Linas LY2H

[@rst5nn]

Linas, Could you do one more PAIN test. You can set elephant (s9 or s9+20) signal e.g. at 14.050 and walk though band from 14.000 to 14.100 kHz and count (notice) how many CW station (phantoms) you can hear.

[@Linas_LY2H]

Thanks for the idea, I’ll put it on my future tests list. Someone has commented here already about phantom CW signals he hears in truSDX. 73! Linas LY2H

[@luizcolossiPY3DU]

Hello DR OM. Congratulations on the tests, I'm already sharing. I bought the QCX mini as a kit in 2020 and now as a kit the DL2, the latter without a printed manual, only videos with a lot of time... little clear information about the construction and a lot of confusing information. I bought it with the Lo and Hi bands pcb The Hi bands pcb, I'm already testing it and I didn't like it. Now I'm finalizing Lo bands. 72 es DX...I'm buying another QCX kit for 20 meters. PY3DU, Colossi.

[@larspregge6420]

The (tr)uSDx is a cruel cheapy TRX. BUT: It show how much you can get from cheap hardware. Lie the 602 (or so). cheap but effective mixer. The (tr)uSDX opened the world for other cheap SDR, as the QMX. I hate my (tr)uSDX, but i love the work from the developer of this little piece of hardware. They made a awesome great work, as taylor did. @7:50 too much connectors.

[@brianfields4479]

Hi, great video and great radio the qcx mini, it is exactly what I am looking for. Is it only one band ?

[@Linas_LY2H]

Thanks for stopping by! Yes, it's a monoband radio by design, but there is more information on this in the qrplabs iogroup. 73! Linas LY2H

[@brianfields4479]

@@Linas_LY2H thanks linus, just ordered a 20m version, see what i can work from zl.

[@ebenfourie9057]

Hi Linus, any chance of you repeating this but with a QMX ? So comparing SDR vs SDR.

[@Linas_LY2H]

Hi OM, sure, why not :) But not because of "comparing SDR vs SDR". In my experiments, I compare the performance of radios, independently of technology, employing the parameters that are universal for all, thus, comparable, like sensitivity of the receiver, or ability to cope with strong signals nearby etc. BTW , the radios in the Sherwood's list are ranked exactly by their performance, independently of their technology. And it's only natural to do so , IMO, otherwise , what should I compare the hybrid radios with if following the principal of "comparing sdr vs sdr"? Hybrids to hybrids, as they are neither pure analogs, nor pure sdrs? :) Comparing the performance , independently of technology, IMO, is the only way to get more or less objective picture of the radio and it also helps a customer to make a choice between the technologies. Like, I see nothing wrong in comparing , for example, the performance of digital filters in my FT-710 to a crystal filters in my Elecraft K3. They, obviously, are incomparable by their nature , but they both do the same job- digging out for me these weak signals out of the noise, so I can hear the difference, if any , and I can make a comparison. Analogy in the automotive world, for better understanding, would be a perfectly legal comparison between the mileage on one charge of an EV car and the mileage on one petrol tank of an Internal Combustion car. Thanks for watching, stay tuned for more! 73! Linas LY2H

[@Johnyrocket70]

Can you add a filter to that model. I know there's a lot of different mods you can do with the usdx radios. Ssh filter and so on.

[@Linas_LY2H]

I like mods! Please let me know if you come across one on the front-end improvement in the truSDX! 73! Linas LY2H

[@downsouthsafaris6788]

So a few questions:- Who’s tr(u)sdx was it? RoWaves, self built or the only authorised reseller? Was the tr(u)sdx in CW mode? and what bandwidth? There really is no comparison between these two rigs and as you’ve pointed out in CW, a $55 mono band cw only machine is better than an $60 SSB 5 band machine at CW. (In reality if a group buy gets it right it’s much cheaper than $60) As with any kit there is scope for much variation in the build quality and the amateur sourcing of components. A better comparison would be the KX2 FX4CR and tr(u)sdx especially to see the difference in reception $1050 of plane tickets that the built trusdx gets for the price of a kx2 (that said and sone I have a trusdx and will eventually get the kx2)

[@Linas_LY2H]

Hello. As it is said in the video: It was the only authorized dealer’s from China (tr)uSDX. Yes, the (tr)uSDX was in the CW mode, with 200Hz filter on, AGC off, as was the QCX-mini. I have only conducted some tests in my video on both rigs without labeling them “this is good” or “this is bad”. I only said “this is noisy”, “this is quiet” - pure facts one can hardly deny. But if you like noisy rig because it’s cheap and multi-band - nobody can stop you from buying it. I, personally, have two of them, not because I like poor reception quality, but because I like the new and simplistic approach in SDR design and I believe it will get better and because this rig is ideal for experimenting. If I want to take part in the QRP contest or activate a park with more or less decent success, I have few other , much better rigs, KX2 being one of the best among them :). Unfortunately, I don’t have the FX-4CR, thus can’t make the comparison you are talking about. But if you have this chance, I’d like to hear about your findings. Good luck. 73! Linas LY2H

[@NeilHoward]

It is a shame you had the "adapter stack" attached to the tr usdx. So it DID actually have a bit of antenna, so the test was not equal in the "silence test

[@Linas_LY2H]

Mea culpa :(

[@TheArtofEngineering]

The "birdy" in the Tru SDX might be picked up from the QCX mini ? (plastic case). Also do the 2 rigs on CW have same audio BW? Gotta say ....I do love a good subjective analysis as MATHS gives me the heebeejeebees!! Like my children, once I adopt a rig it is loved warts and all. Thanks for this video. 73 de VK2AOE.

[@Linas_LY2H]

Thanks for watching! Yeah, I love (tr)uSDX, I've got two of them! Great material for experimenting! It may be the birdies , or at least some of them, could have been picked up from the mini's VFO circuitry , even if it does not seem the case to me ( the no-bandpass-filters front-end design is the real problem, IMHO), it is still worth of another experiment :). The plastic case, yes, it is obviously a good reason for any anomaly :), that's why very rearly we see HF radios in plastic cases. The most plastic-looking IC-705 has really heavily shielded modules and blocks inside. The truSDX has not... But I really liked 3D printing of this case on my own printer, it's also a part of fun with this project! So, let's have fun and Merry Christmas and the HNY! 73! Linas LY2H

[@TheArtofEngineering]

@@Linas_LY2H Yes Merry Xmas...snow for u? ....blazing heat for me!!! 73

[@hpbear101]

I really enjoy my (tr)uSDX I've made a lot of CW and SSB qso's with it and I am totally amazed how much capability comes in such a small package. 73 N7BYD

[@willieb6529]

(tr)uSDX users know how to manipulate settings and mode for higher volume without bad audio... this video, while interesting, is not a good comparison... why? multi-band vs monoband... internal architecture differences... different purpose rigs.... hardware differences... also,it would be nice to compare supply chain availability... cost is the same for the rigs... i have both, but only the (tr)uSDX gives me five bands, multi modes, built in key, and ability to listen to AM MW BCB

[@johnwest7993]

So a dedicated single-band CW-only cheap rig does a lot better on CW than a cheap 5 band multi-mode rig does on CW. No surprise. Now compare them both on multiple bands on SSB, then on AM, then on FM. The fact is, you are comparing apples to oranges. Is a sports car better than a truck? It depends on whether you want to haul a load of gravel, or drive a twisty mountain road.

[@Linas_LY2H]

Thanks for your comment. I’m sure I am comparing oranges to oranges as both radios, as it is stated in the video, were on the same band, on the same mode CW, with the same 200 Hz filter engaged, with the AGC off, both connected to the same external speaker and the battery power supply. The key-word here is the “equal conditions”, not the price of the radio, color of the box or number of bands. If I were comparing 2m FM radio with 20m CW QCX, then you’ve been right with your car parallel. But If both rigs can do CW on 20m with the same filter width and AGC status, they can be compared in this field, independently from what else each of them can do (may be having a nice built-in LED torch or something :)). Actually , by applying equal conditions and the same methodology, any two radios can be compared, in the range of their capabilities, of course. An interesting fact, by the way, is that (tr)uSDX is a derivative of the QCX and they have lots of in common in their schematics (there is an interesting article on that on the QRPLabs site),so this makes these two radios even more comparable. Best Regards, 73! Linas LY2H

[@Aimsport-video]

Correct the feature sets are apples/oranges. But not sure people drive a sports car and a truck at the same time unless perhaps if it’s a Tesla or Rivian truck. For those doing CW on a band, this video is extremely relevant. Sometimes more is less and less is more as they say.

[@Sam-sp7li]

@@Linas_LY2H This is great, thank you. Also comparable are the two radio's similar price point. It seems that the (tr)usdx team had to make a bunch of compromises to get the rig's awesome feature set. There's no free lunch, and for lots of people that might be fb! I love my QCX mini, but the ability to do lots of things - albeit just okay - is very tempting.

[@Linas_LY2H]

@@Sam-sp7li I agree, there is no lunch for free :). I, actually, like the truSDX not for its performance, which is poor, but for it’s original SDR design as an example of how simple the digital radio could be. I’m also sure the guys who created it will find the ways to cure the flaws which are now obvious. 73! Linas LY2H

[@lichtbild2740]

Always learning something new and useful. Thanks Linas. Have a nice new 2023

[@barrybogart5436]

Thanks for your test. I have a TruSDX, and my only other reference is a KX3. I would very much like to see a comparison with the FX-4C as I am mainly interested in SSB performance: kzbin.info/www/bejne/qYGvZpiDprppncU 72, VE7VIE

[@Linas_LY2H]

Thanks for watching! I've only seen the FX-4C in some YT reviews, first impression is it's a nice radio. But I know nothing about the schematics etc. Could it be a derivative of the famous M0NKA design? If I ever have my hands on it, I'd love to make some tests! 73! Linas LY2H

[@ai5dd]

Awesome, thank you. I have a QMX in the queue. Subscribed 72 de AI5DD HNY

[@Linas_LY2H]

Thanks and HNY! QMX is good already and will be really cool with final version of the firmware and bugs fixed! 73! Linas LY2H