3. Alinco DX-SR9 Hybrid HF Transciever

dxsr9topThe Alinco DX-SR9 is a 100 Watt Hybrid SDR Transceiver. This Hybrid transceiver gives you the familiarity of a convention transceiver with the ability to couple it with SDR software to take advantage of such features as a waterfall display, additional filtering, etc. The Alinco DX-SR9 is basically an entry level HF transceiver aimed at the new ham who would like to experiment with SDR or someone who wants to upgrade from a non SDR transceiver. As a traditional entry level HF Transciever, the DX-SR9 works pretty well. As an SDR radio it does have a couple of limitations that comes from using an IQ interface that needs to be plugged into your sound card rather than Direct Sampling. The IQ interface limits the SDR bandwidth to around 48 kHz, which is perfectly adequate for monitoring 24 kHz of signals on either side of the frequency you are tuned. However, some users may find this restricting. The other slight problem is that Alinco could have done a little better job of balancing the IQ input. This imbalance shows up as a slightly lighter area on the right side of the waterfall display in most SDR programs. These two small quirks though don’t diminish the fact that the DX-SR9 is still an excellent bargain in a SDR Hybrid Transceiver packing 100 Watts. Software support comes in the form of KGTRX which is actually a competent SDR program and supports most all the features of the DX-SR9, most importantly transmit. As a SDR receiver only the DX-SR9 can be used with HDSDR or Studio1 by downloading the DX-SR8 ExtIO. At a price of under $800 street, the Alinco DX-SR9 has no real competition in the 100 watt SDR transceiver class.

Low Cost
Easy to use
Relatively east to setup
100 Watt Transceiver
Good software support with receive only with HDSDR and Studio. Receive and Transmit with KGTRX
FM Repeater Mode

No 6 meter coverage
Bandwidth limited to 48 kHz
Slight imbalance in IQ output
Requires additional Alinco ERW-7 cable for computer control approx $60

Price – $720 to $779 Street

One to Watch!

Hack RF One
Hack RF One

The Hack RF One is now available for preorder through NooElec for $299. The Hack RF One has just recently began shipping to its Kickstarter supporters. The Hack RF could possibly turn out to be the best new SDR product of 2014 with it’s wide receive range and very large sample rate plus the ability to transmit at low power. A large number of these units were sold to its Kickstarter supporters which is a good thing because that means possibly some interesting applications may begin to appear much like with RTL2832U. Like most new products, the HackRF may take awhile for the software to mature so even if your not ready to jump in just yet, it’s worth keeping and eye on. HRS has been experimenting with the Hack RF for several months and it does indeed look promising. At this time the only software support is available from SDR Sharp and GNU Radio. Depending how it goes, the Hack RF One could be the next big thing in SDR radio.

Here are the general specs:

  • 10 MHz to 6 GHz operating frequency
  • half-duplex transceiver
  • up to 20 million samples per second
  • 8-bit quadrature samples (8-bit I and 8-bit Q)
  • compatible with GNU Radio, SDR#, and more
  • software-configurable RX and TX gain and baseband filter
  • software-controlled antenna port power (50 mA at 3.3 V)
  • SMA female antenna connector
  • SMA female clock input and output for synchronization
  • convenient buttons for programming
  • internal pin headers for expansion
  • Hi-Speed USB 2.0
  • USB-powered
  • open source hardware
19 thoughts on “The Three Best Low Cost SDR Radios You Can Buy Today”
  1. Don’t forget the Funcube Pro Plus !
    A very capable receiver from HF to UHF.


    1. The FCD range is excellent. Howard himself is a rather agreeable chap also. He’s done a lot for our group at AMSAT-UK

  2. Purchased an AFEDRI after reading your review. It was well written and informative. Would like to see articles more often.

      1. Late to the post party, seeing how this article is from June of 2014, but SDRPlay is now selling for $150. I picked one up at the local HRO store. I’m very impressed with it. Unfortunately, SDR# isn’t playing well with some SDR radios, but I use SDR Console and HDSDR mostly these days.

  3. yes Excellent article, i think i’ll go for the afedri too for simplicitys sake- i never managed to get my RTL2832 dongle working as an SDR- don’t mind though- it was very cheap and i can still watch TV and listen to DAB on it.

    is FCD any easier to set up than the RTL2832 dongle?

    the Alinco SDR handheld which i had working initially (i even posted some Wav files) now doesn’t work due to some stupid software update from microsoft affecting my system.
    i had the same problem with spectrum lab,
    when funds allow i’m going to go back to having 2 laptops -one for dxing which i never connect to the web and one for work stuff

    will be following ‘Radio Spectrum Processor’ from SDRplay with great interest- seems perfect for FM broadcast dxing

      1. Hi Bill, for DAB I just used the supplied software.
        I don’t have the skills for anything beyond that 🙁

        like sandro i’m now using an (expensive) sdr with the if output of my Icom RX

    1. Haven’t had the opportunity to test the Airspy yet to see how it compares to the SDRs listed in this article.

  4. We are pleased to announce release 1.8.0 of the API for the SDRplay RSP. This is a major upgrade to the API with new features and an improved gain map which should result in improved performance over a key portion of the gain control range. Currently this API is available for Windows only, but versions for Linux and Mac OS and Android will follow shortly.

    The API now incorporates automatic post tuner DC offset correction and I/Q compensation. This will almost completely eliminate the DC centre spike that was previously present in zero IF mode and also correct for amplitude and phase errors in the I/Q signal paths that can lead to in-band images when strong signals are present.

    There is a new gain map for the RSP which should help improve the receiver noise floor for gain reduction settings in the range of 59-78 dB. To achieve this, the IF gain control range has been increased from 59 to 78 dB. In addition, the user can now turn the LNA on or off at any point within the IF gain control range. This means that the LNA can remain on for gain reduction settings of up to 78 dB, whereas previously the maximum gain reduction that could be attained whilst the LNA was on was only 59 dB. Being able to leave the LNA on will result in improvements in the receiver noise performance for gain reductions in the range of 59 to 78 dB. The upper 19 dB of the IF gain control range have now been disabled. In practice this part of the gain control range was useless as trying to operate within this region always lead to receiver overload even when signals were very weak.

    To fully exploit the features of this new API release, we have also issued release 3.5 of the ExtIO plugin. This plugin will work with HDSDR, SDR sharp (releases 1361 or earlier) and Studio 1. Automatic I/Q compensation and DC offset correction will work with later versions of SDR sharp, but we will need to update the native plugin for users of these later versions to be access the new gain map.

    Similarly, users of SDR Console will gain the benefit of automatic DC offset compensation and I/Q correction, but will not yet be able to access the new gain map. We hope that a version of SDR console that unlocks this feature will become available in the near future.

    Until a new release of SDR-Console is available, you can copy the API into the SDR-Console installation directory…

    from C:\Program Files\MiricsSDR\API\x64\mir_sdr_api.dll to C:\Program Files\SDR-RADIO-PRO.com\mir_sdr_api.dll

    The API installer has also contains an extra certificate to be more user friendly for Windows XP, Vista and Windows 7 users.

    The new API and ExtIO plugin can be downloaded from our website at: http://www.sdrplay.com/windows.html

  5. Hi
    I have got both , RSP and AFREDI.
    From side dirver ,RSP is more complete and have the best compatiblity with all software.
    Afredi have less bandwidth but a signal more strong and clear.
    Extio.dll of AFREDI aren’t so complete like RSP.

    Now i use AfREDI with first IF of my icom 7410 and i can say that i prefer to listen signal by HDSDR

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