After getting my feet wet with the UBITX I ran across this interesting sounding project:



I sent off the Gerber files and I'm waiting for the boards to arrive by slow-boat as I am in no hurry.? If anybody else might want to play around with this I will have extra boards.? Minimum order was 10 PCB and with shipping was a whole $24!

Hope I'm not breaking any rules.

73,

Justin B.
KI5GKD

Justin,

FYI, There is a Groups.io for that work.? It is here:
/g/ucx

The original project was called ?CX, which the group felt was too close to the QCX/QSX names that are used by QRP-Labs.? The official name is now ?SDX or uSDX though the Groups.io page (like this page) has a different net ID.

Have fun!
73
Evan
AC9TU

Hi Justin,

That article looks interesting. I wouldn’t mind buying one of the PCB’s off of you. How does $5.00 sound, is that fair? I usually look at this group each day so let me know what you think.

73,
Robert, AG6LK?

Robert - That's about what I was figuring, definitely no more than that and maybe less.? I already have a few Nanos since I couldn't use them on the Raduino with the header soldered on opposite and also have a couple of the clock boards so just need to put in an order to mouser or DIgiKey for the pieces-parts I don't have.? That will probably have to wait until fall as I am heading to the OK mountains next Saturday and won't be back to the home QTH until fall.? If the boards don't get here before I leave I'll have the XYL carry them up with her in May and I can mail them from the cabin.

73,

Justin B.
KI5GKD

uSDX enclosure :?
73 - Pierre - FK8IH

I like building and have built a BITX 40, uBITX, QCX, QCX mini and a Barb WB2CBA v1.02 uSDX. The first thing to know is that unlike the uBITX or QCX, there are several hardware variants with different capabilities and technology (SMD vs through hole). If you are interested, spend a little time thinking about what development track you want to build.

I posted a few articles on the uSDX here

and here

and the groups.io WIKI is useful.

BTW - if you are interested in SDR check this out:

note this talk "Ashhar Farhan VU2ESE - sBITX - An Open Source SDR that YOU can hack!"

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? 73
??? Bob? KD8CGH

Bob - I have ordered the "through-hole" version since I am a lot more comfortable with that type of construction.? I will read more when I get time.

Pierre - That's not a bad price especially with all the "stuff" that comes with it but I'm not really sold on the color!

Justin
? I made the same choice for through hole. I built the earlier Barb variant with plug in band boards using a Si5351 module board.
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? 73
??? Bob? KD8CGH

Justin,

Do you know what version of the board you ordered? I see there is a version 1.02 that seems to be the newest. I guess they had some problems with the v1.01 but they’re fixed in version 1.02. I also have seen a complete Digikey parts list on on one site. It looks like the parts only came to between $35 and $40, depending on the different choices yo bought.

73,
Robert, AG6LK?

Robert,

I ordered boards using the V1.01 files which were the latest on the antrek site, it appears there some mods that need to be made to the board - boards are done and shipped.? As far as the parts list goes, I found one but need to look up every part and order.? Would be nice if there was a DigiKey BOM...

73,

Justin B.

I have the V1.02 boards with the plug in band modules.

Later versions had 3 switched bands and he also released serial resonance band boards and a 10 watt amp.
Best start for Barb track is
from there you can go to different versions and add ons like 10 watt amp.

I have a few extra V1.02 boards and band boards if anyone is interested.

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? 73
??? Bob? KD8CGH

Bob,
I'm interested in building the uSDX. What is the cost for the boards & shipping?
I'm interested in the 10 watt build as well.
I'm in zip code 44124.
Dave KE8PXV


Sent from ProtonMail mobile

Justin,

I found the website where I saw the uSDX BOM for Digikey. Here’s the URL:?

/g/ucx/files/WB2CBA%20uSDX%20PCB%20V1.02%20Digi-Key%20BOM

Just click on the URL when you get to the website you’ll see an odd file extension but you’ll be able to view it and download it. I hope this helps you.

73,
Robert, AG6LK?

The smart, handsome, modest author of that BOM would like to point out that it is for V1.02, not V1.01, so not ideal for Justin.
There is a V1.01 BOM here /g/ucx/files/uSDX.xlsx

And, although the BOM Robert mentioned is a true work of literary art and useful for DigiKey ordering, there is actually a much nicer interactive one for doing a V1.02 build here
/g/ucx/files/Bare%20Essentials%20for%20version%201.02%20Build

Firmware, 3D printed case designs and other useful things are in the ucx groups.io files section.
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? 73
??? Bob? KD8CGH

Robert,

I have the boards and have completed one and it works nicely!? If you still want one, or two let me know.? I have not hooked up a mic and transmitted yet but the receiver works great.? Maybe I'll try to fry the finals tomorrow! ;-)

It will be fun to play with but I don't think my V6 should worry about being replaced as it just works so good!

If anybody else would like a board I'll have 8 to turn loose.

73,

Justin B.
KI5GKD

On Mon, May 31, 2021, at 09:33 PM, Ashhar Farhan wrote:

When someone finishes the usdx build, I would like them to measure the opposite sideband and the audio distortion. I am curious how well it works.

I too would be interested in actual performance data, most importantly the efficiency data.? Efficient portable SSB operation was the original goal of the ?SDX, gaining the Class E power efficiency for SSB use.? I have not seen this data for any of the kits offered, nor is the ongoing effort to constantly improve on the efficiency while maintaining reasonable signal quality.? Since it is the efficiency of power use as the goal, as long as the signal is intelligible and within legal requirements, then the goal is met if it has better power efficiency than similar SSB transceivers.? That would be total power for operation, not just the finals.

I do not mean to criticize the effort.? It is amazing what has been done.? I am just not sure that the original goals are still the focus of the group.

At the same time, while interesting, I can say that I will not be building one.? If there were a Teensy or another better-specified microcontroller I might be.? One reason for my interest in the sBITX that Ashhar Farhan is working on now.? Based on data from him so far, portable operation would not be one of the major goals.? The Raspberry Pi is a real power hog, up to 10 watts just to run it, and that does not include the display.?

So far the superheterodyne seems to be the most efficient for SSB use.? That is NOT the case for CW as Hans Summers has proven with the QCX Mini.? I could be wrong about this, as it is not based on any real data that I have analyzed.? SDR is the trend as Icom and Elecraft are showing with their QRP portable rigs.? They still have a standard PA and are being driven by features more than power efficiency.

The above are my thoughts, others will be different, and that is OK.? I am always open to new data to change my view.
73
Evan
AC9TU

开云体育

Raspberry Pi power consumption figures:

There is an effort to port the code to a Pico Pi which has dual cores and much better capabilities, but is still a controller and much less power hungry than other Pi models.
/g/ucx/message/6950
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? 73
??? Bob? KD8CGH

开云体育

The capabilities and included functions of an RPi PICO are so drastically reduced compared to an RPi 3 or 4 that there is almost no comparison. That said, for its original design, an RPi at the heart of a transceiver like the uSDX is, to use a phrase "over-kill" but, just imagine what can be done with the Bluetooth, WiFi, and Ethernet connectivity by an enterprising experimenter, not to mention the HDMI display and USB ports that can have mice and keyboards attached. How long before an enterprising amateur adds the missing software bits to build a single-box, all-in-one digital mode transceiver with built-in logging?