Thank you. This answered a question I had. I am in the process of building a version 1.01 board and will complete it. I was going to buy one these Chinese ones to do this exact comparison. You saved me some money.
Great video! Will wait for your own rig to become available through your site. Give yourself and your loved ones around you a worthy price-point deserving of your hard and sleepless efforts! Honestly, anyone who has ever worked on the bench for hundreds/thousands of hours know you should be justly rewarded! 73 WA4ITD
Excellent video. And excellent design of yours. Been waiting for a radio exact like yours for years for survival purposes. bought the chinese smaller black version with controls on the end before I found your channel. Now I want to change out that FET and anything else that isn't spec, like the caps they got wrong. I would have gotten the sandwich but I don't have enough time to build it
Well that just shows the difference between taking a look at the schematics and sending a BOM to a factory and saying make me 10k of these and then there is you Manuel who looks at the schematics and immediately spots the mistake .... and knows without even testing that it will not be effiecent... I also think you are maybe being a little hard on yourself, as by now amny people in the hobby know that the chinese gear is not up to scratch compared with say the big three, or in this case a guy looking to make a small, cheap, effiecent, in spec transciever, but fair play to you for going down the route and good on David for helping you to explain .... top draw video... thank you... Yoki..
Thank you for your review. I was trying to figure out the shipping/customs/etc fees from the vendor. Now, I don't need to continue. And, a pocket heater might be helpful during the winter.
Hey, I am very sorry that Your work was treated like that. Please, do Your own version, put it on sale on Your page. I bet You will receive plenty of orders because Your rig is awesome.
Hello it’s nice to see the real transceiver and also the bad version from china!! They have made money that does not belong to them and made many errors In the build of the transceiver they have. Kind regards Peter G0LVG
All well and good but some of us older hams are not able to build your radio with age related tremors. We have no other option but to purchase an assembled radio. All the things you said are true, and your evidence is indisputable, but again we few non kit builders are left out in the cold. A confusing mess about where to turn. Tommy N4KBM.
I suppose most qrp radios from china are deficient in harmonic and spur suppression. As not too many people have a sa the bad tx qualities go unnoticed. Thanks for the video!
Hello, first of all, congratulations on your work. As in my case, I think there are a lot more people, that with computers we handle ourselves well but we have problems when it comes to building them, we do not have the necessary tools or knowledge and especially when it comes to smd technology. I think it would be a very good idea if you could sell the assembled equipment, I would be one of the first to buy it without hesitation I also think that it would be the best form of financing without having to ask for donations, I have already made one of € 10
I'm not sure how subtracting the receive current is valid in the transmitter efficiency test. The current drawn by the VFO, display, etc. is still part of the transmitter's current. If the point is to find efficiency of the final power amp stage, it's interesting, but the overall current is more important for portable QRP operation.
Wow! Well, there's a lesson learned in this video for sure, Manuel. Too bad. It's a nice ergonomic design and it's a pretty little box. If only the exterior nice was duplicated by an inner nice. (I thought David's videos were interesting; when you got this one and went through it like an engineer, well, that told the true story.) Stay safe & healthy! 73 de W8IJN
@@dl2man Yes, I did. Going by looks alone from a distance, it looks ok to me. Hands-on it might make a difference. . . . Researching the output tranny I can see where it is less than optimal. All in all, yes, it's a ruination of what is/was a good idea.
Ok, but what do you recommend ? If this radio gets too hot in the pocket, transmits on multiple frequencies, heavy as a brick and limited usage. What do you recommend instead? you forgot that part. Something that does all the HF bands including 2m / 70cm as well. in QRP for emergency SHTF.
No I did not forget that part. I just did not want to give any advise in that direction. As Originator of the Schematics they used, I can only tell you that they did a bad job. That´s the message of this Video. I´m not trying to sell you SHTF Radios ;)
OK Manuel. Thanks for information but, We can find Chinese model mounted on many websites. The best answer it's the possibility to find the yours for people without knowedge of electronics. I have it and for me will be a pleasure buy yours, and help your work and compare it. All we know that yours is better, Of course! but nobody in your proyect now, think on operators without free time y without electronics knowedge and the chinese shops yes. This is the difference. My best 73s
The whole point about uSDX was to learn electronics and built confidence to use a soldering iron. A rig with that performance with such a low parts count ? I mean come on... When there's a will there's a way. Might sound harsh, but if people insist not to have time for a 2-3 hour built of a pre assembled kit, they maybe deserve to pay 200$ for the Chinese rigs and get this performance.... They do not hurt me with that 😂
@@dl2man Agree. As you can see today, the success of the Chinese copy is overwhelming. That means that not everyone is willing to spend their time building a transceiver. It is very good (I UNDERSTAND IT) to encourage the introduction to electronics with your team but the Chinese success is there. But you can keep thinking what you want but it is another way to have a cheap and very useful transceiver as an emergency or for SOTA / POTA activations for example for people without electronic knowledge. If you make it easier, surely your project will be more successful despite having some higher costs. But that only depends on you and your policy on the project.
The FET of my Design was IRLML2060. Tiny and pretty sensitive little FET, easily blown by bad SWR. They replaced it with IRF510 in some cases, and 3xBS170 in other cases. Both can be used to some degree, if the Filters are beeing matched to the FET / Re-Designed around the FET.
@Joe Yes. I'm not a great at soldering but If I can get someone to do it for me I'll give them 100 bucks to buy everything and make it for me. If anyone wants to just let me know!
There will NOT be a completed rig from me/us. In order to offer/provide a completed rig within Germany/EU we´d need al kinds of certificates and paperwork. I know it´s legal to buy and use a device as licensed radio amatuer, but it´s illegal to produce and sell. If you sell those commerically, legal requirements need to be fulfilled. Won´t go through that painful buerocratic process for my hobby. In the end, for me it´s just a hobby to enjoy and relax. Not a buisness.
Spielzeug zum basteln. Ob man etwas verbessern kann .... oder es kaputtlötet "be or not be" ist hier die Frage. Sicher ist der orginal deutesche Prortype (auch gemessen) besser. So etwas sollte dann auch zu einem erträglichen Preis vom Homemadehersteller angeboten werden. 33% materialkosten, 33% Arbeitsaufwandt und 33% Gewinn = Angebots/VK-Preis. Wie sähe sowas aus?
After what happened to the MCHF (it was also copied and marketed illegally as the RS918) I guess it is no surprise that your design was also copied for profit. We are constantly told how clever the engineers are from that country so why do we not see their clever original designs on the market? The amateur radio market is very small compared with consumer devices, so it must be copy shops who just do this as it is cheap and easy to copy a design and see how many willing hams buy them. Oh, I forgot. there is an audio amplifier, speaker and a battery in this device, not a lot of engineering excellence required for that. So sad to see. Thanks for this review and I appreciate your restraint in describing this device as a weapon or pocket warmer! 73 vk1da
It is a shame that the device has such bad transmission values. I mean, efficiency says it all. But the weight is not that bad because at least a large battery is built in. And I think that's great, but it's a little harder. The orange device can also be used for self-defense by killing the enemy with the additional battery or strangling with the cable. Hi
There will NOT be a completed rig from me/us. In order to offer/provide a completed rig within Germany/EU we´d need al kinds of certificates and paperwork. I know it´s legal to buy and use a device as licensed radio amatuer, but it´s illegal to produce and sell. If you sell those commerically, legal requirements need to be fulfilled. Won´t go through that painful buerocratic process for my hobby. In the end, for me it´s just a hobby to enjoy and relax. Not a buisness.
Why subtract the receive current? The rig in TX mode draws a value of current ….and in receive mode draws much less …. But subtracting this value to derive efficiency…. When the rig is still drawing that current seems counter intuitive?? If the power is being consumed we need to consider it? Or am I missing something?
@@dl2man I just thought that once the rig is in transmit then the current due to receiver sections would be negligible as the audio is not “on”….. the RF AMP is earthed etc, so the current would be less? I guess it still gets you closer to the most accurate measurement, doing the math that way. By the way congratulations on the work on this amazing rig! I wanna build one! 73 de VK2AOE
No, you don´t need a reflow oven to build it. The new project will be set up to have it pre-assembled by any Pick and Place Servive (like JLC-PCB). You can source the parts for yourself and either hand solder it, or use a reflow oven. But I have my prototypes pre-assembled.
I designed the Filters for IRLML2060 (a tiny SOT23 FET). I calculated them for 4Watts out, because the difference between 4W and 5W is tiny, but I have a lot more safety margin.
Very good video and I like your sense of humour! The spurious comparison should really show both rigs results under identical test conditions. Do you know what FET the .CN product uses? Can you explain the results further by finding the key significant differences in the respective data sheets? 72, 73!
Hi Paul, I don´t think I will be wasting my time anymore with these chinese rigs, and instead use my free time on my own development. I feel, that´s better used, and I´ve made my points already. Anything more would be just repetition.
@@dl2man Yes sure, I wasn't suggesting you redo anything, time to move on. Yours are the most structured and analytical comparisons I have found, thankyou. So far I have not found anything that represents a test of receiver performance or transmitter quality. There are some videos of receiver audio which are helpful in knowing what to expect. And nothing I've found on transmit SSB signal quality. I have a suspicion transmit audio is marginal and while good enough to make a QSO, not really satisfactory for long term use, or for driving any kind of amplifier. Videos of short QSOs in marginal conditions where much is made about QRP etc do not dispel these thoughts. I do not wish to overbake this, I understand that this is a simple rig made all the more appealing by its minimal implementation of SDR. That it works on a ATMega328 at all is remarkable! I will probably build one and see for myself. Thanks for your excellent design work on this highly intriguing project, the sandwich is great design, I love that ! 72 de VK3HN.
You should contract a decent country's factory and produce your own equipament stating "ORIGINAL" on the front panel. It can be a kit but very easy to assemble, for the ones that don't have the time or the will to build it from scratch. That would divert the money to the right guy...👍
I agree. We could make money from it, but from ther very beginning we never were interested in making money with it. This has not changed since. My problem is not, that chinese entered the market with our idea: I appreciate that ! My Problem is the bad quality of the rigs: They did not match our design goals by changing relevant parts and use their own bad PCB-Layouts. For sake of producability, they "improved it to the worse". If they just would have produced my initial design, with the proper components on it, we would not have that discussion.
@@dl2man Thank you very much for your elegant and nice answer Sir 🙏 I understand that you are not moved by the profit, but by the technical knowledge of your fellowman. I really understand you deeply. And you are right: they should copy your great design (not cut corners). Some competent european factory (Germany is great about quality) would make a "by the book" unit. You could even improve your design, and your radio would be the SOTA/POTA/QRP choice (beautiful design, very light, high efficiency). Thanks again 🙏
You love that's cool, This is the test of your Knowledge. Show the math for the "B" field of a magnet, that's the center of a magnet... you will find anti gravity there FACT!!
its such a shame you could not commercialize on your idea - I would have bought it even for 3x price, but I would be sure of a quality. The built it yourself idea is great, but covers too little audience. 73 de LY1H
Fair point, but chinese can provide good quality if it´s controlled. Even my PCB´s are made and pre-assembled in china. By default not a bad thing. In case of the measured radio just badly executed.
So heavy you can use it as a self defense weapon ... that's a huge benefit for Americans who are constantly expecting to be attacked by everyone and everything.
You check also harmonics on sandwich version? Just ask. No offence. I wait for pcb to come from .cz to made your sandiwich version. i am a big fan of your project ! 73 by yo8xcm!
Of course. Sorry, Was not filming that. For me it´s very clear to have every harmonic better then 43dB down, but I should have proven that in that Video for full transparency. Sorry. Will add that next time.
