DL2MAN's (tr)uSDX MINI-MARVEL
The (tr)uSDX is something of a marvel! Okay, so it's no KX3, but neither is it £1500. It's a supremely affordable QRP transceiver which can be purchased pre-built or (if you're into diy), can be ordered as a simple, easy to build kit. Because I'm tight-fisted 😂 I bought mine second-hand from YouTube's TechMinds.
Everything about the (tr)uSDX looks cheap - it's encased in a 3D printed enclosure with all the associated crude detailing and tacky colours. The VFO encoder knob is also 3D printed. The case is held together with bulky screws and it has those stick-on rubber feet that you can buy from the £Shop.
The sound from the built-in speaker is pretty shocking and the audio is generally poor. The receiver isn't particularly sensitive and when sat next to my beautiful little BELKA DX receiver, you feel like maybe you've made a mistake purchasing the (tr)uSDX.
This is a 5-Band radio (mine is configured for 80-60-40-30-20 (but other configurations are available)) providing around 5W output and CW/LSB/USB/AM/FM modes. There's a convenient built-in microphone and PTT-switch (which can even double up as an emergency CW key), making the radio pretty self-contained. Needless to say, you'd be better using an external mic and speaker, but at least they're there as a backup for those occasional days when you reach your SOTA Summit and realise you've left the mic at home! The radio has a socket for a CW Key (straight or paddles).
The receiver's noise floor is fairly high, but again, you have to remember the price point of this radio and accept the fact that it's not your DX base station - it's your "stick it in your pocket" radio, your "pop it in the glovebox" radio. And when you're sat on the beach or on top of a hillside with a bit of wire, you'll be pulling in plenty of signals strong and loud enough to be able to have some fantastic QSO's in any mode you like!
As soon as my (tr)uSDX dropped through the letterbox, I quickly connected it to a 9V supply and an EFHW and tuned around 40M. On 7.144 I found PA0PIW and although he was in a mini-pileup, I thought I'd shout into the built-in mic and see if he could hear me. He almost instantly read back my callsign and gave me a good signal report! That was very pleasing and I look forward to taking this little beauty up to my local Sota point to see just how far I can get. My second attempt got me a 55 from F4HEC in France (he’s the one featured in the recording above).
Navigating around the (tr)uSDX's operating system is fairly straight-forward. The primary function of the rotary encoder is (as you'd expect) to control the frequency of the VFO, but if you push it down and turn, it controls the volume. Single pushes of the knob alters the tuning rate and a double-push changes bands. Single-clicking the Enter Key changes modes, while double-clicking changes filter width and a long push brings up the RIT function. Nice!
The rest of the radio's functions lay in the Menu and it's all surprisingly intuitive - no doubt thanks to the software skills of DL2MAN's partner - PE1NNZ who's done a fabulous job. When you first get hold of your (tr)uSDX you can put it into 'Practise Mode' so that the PA is shut down while you learn your way around the radio. Speaking of PA, there is a connector on the side of the radio to allow you to connect to an External Amplifier.
DL2MAN's website is a great place to learn more about the (tr)uSDX and its heritage; there's lot's of great tutorial videos there too. Manuel seems like a real nice character and his videos make for easy watching. His command of the English language is pretty good too. There's also a very useful FORUM.
The (tr)uSDX can be run on a wide range of voltages using the small DC connector port and can even be powered from a 5V USB power pack. At 5V the TX power is limited to 500mW but even that is a great feature for those wishing to play at the lower end of QRP levels. This USB port can also be used for CAT Control and Programming.
As I mentioned earlier, the OLED screen provides lots of info and can be tailored to suit your personal preferences. You have the frequency, the VFO indicator, S-Meter, Filter Width, Rx/Tx indicator, Mode, Tuning-Step and even your CallSign. Things like the S-Meter can be altered to show reflected power, forward power, swr, watts, efficiency and more, but the latter can only be done in CW mode.
Another great feature of the (tr)uSDX is the built-in CW Decoder! Again, just think about the price of this tiny transceiver and ask yourself would you really expect a CW Decoder to be included?? I wouldn't!
Note that I fitted an SMA to BNC adapter but it leaves a gap, so I inserted a brass ‘Cup Washer’. Perfect fit! I also use a compact (but very clear) plug-in speaker from Amazon. Highly recommended!
|Super simple to build!|
|Quick PSKR Test - 3500 miles|
|Quick RBN Test - 3400 miles|
Being a lowly M7 licensee, I have no knowledge of electronics but I figured out from the (tr)uSDX details on the net that I could possibly get this TYT Mic working, so I tried to get it right in my head before giving it a go. I sketched this little schematic...
There are lots of videos of the (tr)uSDX on YouTube, so go there to discover answers to any questions you may have about the radio. I hope you enjoyed this little review of the (tr)uSDX and consider ordering one for yourself - I'm sure you'll love it!