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Comment by znpy | Hacker News Reader

Question: can I use LimeSDR and some SDR software to save on hardware and not get a Yaesu or Icom ham radio?

I wanted to play with ham radio for a while but I am not sure I want to spend 750+ Euros for a Yaesu station.

It would be a good proxy for those radios, but if you're licensed and are simply looking for an inexpensive transceiver, Baofeng UV-5R radios can be found on Amazon for ~$20 and will get you working right out of the box.

If you try to mock up a station using a TX/RX SDR system, it would probably much more expensive and require significantly more hardware.

He's probably looking for an HF rig -- baofengs definitely don't do HF. As someone else said, the LimeSDR would work well, just need an amplifier because the power out is on the order of milliwatts.

> He's probably looking for an HF rig

Indeed.

Absolutely, but you'll probably need an amplifier as these things tend to be ~1mW-10mW output power.

LimeSDR is not that great for HF work - the chip is really designed for cellular frequencies. Although you can technically tune it to lower HF freqs, it really struggles at that range - there is lots of evidence on the forums that demonstrate this.

Yeah, something like uBitx[1] + amp may be a better combo.

If you're interested in digital modes than 10w is usually enough for PSK, JT* and FT8.

[1] http://www.hfsignals.com/index.php/ubitx/

Check out the SDRPlay RSP2[1]. It is less expensive and covers 1khz to 2Ghz. It comes with nice radio package (SDRuno) as well.

[1] https://www.sdrplay.com/rsp2/

I've been dreaming about a project where a full-duplex amateur satellite LEO ground station could be based around a limesdr with a daughterboard, but that'd be for 1.2G / UHF / VHF and I lack the time, energy, money, and expertise to bring it to reality. Depending on what the IC-9700 price ends up being, I think it could actually be cheaper to roll-your-own radio for this purpose than to buy something off the shelf.

However, for HF (and at this point in the solar cycle, where anything less than 50W is wasting time), it's almost certainly going to be a cheaper and better experience to pair a used 100W transceiver with something like a RSP1A [1] instead of trying to roll your own. This is what I do; I've tapped the IF on my FT-950 and pair it with a rtlsdr for the purpose of having a waterfall. Being able to "see" the bands makes a huge difference.

---

[1]: https://www.sdrplay.com/rsp1a/

> However, for HF (and at this point in the solar cycle, where anything less than 50W is wasting time)

QRP is still very much possible, I don't have any problems with CW, FT8 or PSK31 on my KX3(10W) with a simple end-fed halfwave antenna. It's all about using the right mode for the band conditions.

For voice 100W is still nice to hav but I wouldn't call not having 50W wasting your time.

Of course! I should choose my words more carefully. My point wasn't to say that QRP is pointless, most of the time I spend on radio nowadays is <25W. It's just a struggle, but the reason that you and I seek out that struggle is because we've probably both made plenty of contacts, and we're in it for the sake of being the best operator possible and seeing what we're capable of with limited resources, not for chasing DX with big beams and legal-limit power. For us, a 5W contact with less distance is worth more than a 100W contact that goes halfway around the globe.

That's not how I felt when I first got into radio, though, and I wouldn't recommend that new hams go straight for QRP operation. You're just going to get frustrated.

(PS: How do you like your EFHW? My father has one and we have been really underwhelmed, noise is just unbearable compared to his vertical. For portable operation it might be okay, but I think he's going to replace it with an off-center fed dipole. I'm jealous of your KX3, I've been eying that new Xiegu X5105 and the KX2. Something portable opens up a lot of fun operating scenarios.)

-- 73 DE W9NLS

That's the thing is that everyone has a different idea for ham radio. I went straight to QRP and the digital modes and rarely touch voice(except to chase some SOTA activations).

The EFHW does well enough for me but I'm out in the country so I'm probably fighting a lot less noise. 20m is usually S3 and 40m S1-S2. Love the kx3, if I didn't want to do SDR stuff with the IQ output I could have probably done fine with a kx2.

You'd also probably need an upconverter like the HamItUp (which works for the HackRF).

If you're just using a standard RTL-SDR, then yes, an upconverter like HamItUp or SpyVerter would work.

However, the LimeSDR Mini supports down to 10MHz out of the box, which is "good enough".

If you really need to get the 160, 80, 60, and 40 Meter bands then the converter would be needed, or you can just use the previous-generation the (full size) LimeSDR, which can receive down to 100KHz.

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