Putting the DX-SR9 in SDR Mode

The DX-SR9 is placed into SDR mode by pressing the Mode button until the display shows FM mode. To complete the process you must then press the FUNC key and then the Mode key to put the DX-SR9 into SDR mode. The front panel display will indicate SDR displayed in large letters. At this point, the DX-SR9 effectively becomes a black box SDR radio. All front panel controls are disabled including the front panel mic jack. The DX-SR9 can now be controlled only by commands sent to the ERW-7 cable and the software. This is good in a way since you can’t accidentally make changes to the radio by bumping a knob. However, it would have been kind of nice to leave the VFO knob active so you could use the VFO knob to tune the SDR software if you wanted to. It would also been nice to not disconnect the mic jack. However, it’s not really that much of a problem.


KGTRX Notice the lower gain on the right side and the ghost signals showing on the right side of the display represented by twp vertical bars.
Notice the lower gain on the right side and the ghost signals showing on the right side of the display represented by two vertical bars. As discussed in the IQ section of this article.

KGTRX is included on a CD that ships with the DX-SR9. You might want to check Alinco’s Website to see if a newer version is available. The good news for you that may have used KG-SDR with your Alinco DX-R8 or DX-X11 receivers, is that KGTRX is a much improved application for SDR use with the DX-SR9. While the KG-SDR was extremely basic and offered very few features, you will find that KGTRX offers more features and customization and supports the DX-SR9 very well. It’s still a bit on the plain side and doesn’t offer all the bells and whistles of some 3rd party offerings, but it gets the job done. Plus, for those new to SDR radio, it’s very easy to setup and use. Even though the specifications call for a minimum of a Core I5 processor, it was tested on a Windows 8.1 Core I3 machine and a dual core Atom based laptop with no issues. The Core I5 recommendation is primarily based on helping to reduce transmit audio latency.

Setting up KGTRX is very simple. Under the Settings / Device menu you will need to set the RX IQ Signal input and the Speaker Out to match your soundcard settings. If you are going to transmit you will need to set the TX microphone input and the IQ signal output to match the appropriate soundcard settings.  Finally you will need to set the RS232 Port setting to match you the serial port setting of the ERW-7. If you don’t know, you can always check under the Device manager for reported serial ports. If your PC is pretty simple as far as sound cards and serial ports are concerned, it may auto detect these settings. Once these are all set, you are good to go.

One big advantage of KGTRX over 3rd party programs, is that it can support features that are unique to the DX-SR9. For example it supports switching between transmit and receive, AGC settings, Power Level settings, RF Gain settings, and External tuner. Even though you can use 3rd party SDR programs they probably won’t support these features on the DX-SR9.

The KGTRX displays both a spectrum display and a waterfall display while using the the DX-SR9. Tuning can be accomplished by several ways. You can directly input the frequency and the use the mouse scroll wheel for fine tuning. You can also click on the spectrum display or waterfall display to set the receive frequency. A nice feature is that by right clicking on the mouse, you can move very quickly through the spectrum display tuning. This allows you to quickly sample each signal. The fine tuning step size is adjustable from 1Hz to 20Hz. The listening frequency , s-meter, and filter settings are shown at the top of the screen.  Of course there are buttons and sliders for volume, squelch, and transmit. KGTRX offsets the receive signal away from the center spike to help eliminate any interference that may be generated from the spike. Turning on transmit, KGTRX sends the matching the transmit frequency and mode to the DX-SR9 and audio is sent from the PC to the MOD jack.

KGTRX offers several DSP functions. The  IF and RF filters can be set to several presets by the software or you can customize your own. There is a non-adjustable noise reduction filter, which does a reasonable job of reducing background noise. There is also an automatic notch filter which is pretty effective at removing an unwanted tone in the signal. The 3D button provides a pseudo stereo effect which will push the received audio a little more forward. This actually very useful for making weaker signals more present.

Some additional features available in KGTRX is an IQ and Wav recorder. This can always come in handy in various ways. The IQ recorder will allow you to record the entire 48KHz spectrum for playback later in KGTRX. The Wav recorder will let you record the current receive frequency for general playback with most media players. There is a spreadsheet style frequency memory feature to allow you to create and save frequency presets. A nice touch is that you can move to the frequency you want to save and activate the memory feature and simply click add frequency and the frequency and all of it’s setting are stored. You can also give it an alphanumeric tag. At this writing, the frequencies can’t be sent directly to the radio for storage. There is a Tune button to activate the Alinco external antenna tuner if you have it. The CW key, basically lets you use the mouse button as a cw key if you want. Under the settings menu, KGTRX will allow you to do a few customizations to the display like changing colors of some components and positions of some of the display elements. The gain settings let you tweak the waterfall gain, input gain, mic gain, and output gain. The misc settings allow the user to change the behavior of the mouse wheel, beep volume, filter shape, CW tone, recorder playback behavior, and the IQ tuning area.

Overall, KGTRX ticks most of the boxes and makes SDR easy to operate for beginners or just as an everyday SDR program for casual use for more experienced users. More than likely this will be the program that most of you will use with DX-SDR9.

24 thoughts on “Alinco DX-SR9 Hybrid SDR Transceiver Review”
  1. Excellent review! Nice to see a semi-major manufacturer embracing the improvements SDR offers and including it in their rigs.

  2. Thanks a lot for the review and the Omnirig.ini. It works well with SDR-Radio.
    Is there any (more or less official) list of the Alinco commands?

    73, Uwe

    1. Check the Alinco Forum on this site. There is a list of DX-SR8 commands that seem to be pretty much compatible with the DX-SR9

  3. If only it included 6 meters this would be a slam dunk. I think the KX3 still has the edge, even at 90 watts less power.

  4. Just curious which brands of usb adapters worked and which didn’t. I just ordered a sabrent 7.1 usb card with line in, stereo mic input, etc..

    1. Actually one of the problem devices was the Sabrient SND8. The inputs were reversed. Even though they could be switched in the software for it, the setting wouldn’t always work correctly. The easy work around was to just swap the input cables around. The best performer by far was the Soundblaster SBX external box.

      1. Thanks for the heads up, I will keep that in mind when it comes in. I just got it because it was economical and I am impatient, lol. I will also check on the soundblaster box, I noticed in the videos of the Tokyo Ham Fair that they were running the soundblaster unit.

  5. When you say swap the cables around, do you mean use a stereo to mono splitter and use the stereo mic input?

    1. It would just me a matter of connecting the Left output to the Right input and the Right output to the Left input by using an adapter or by rewiring a 3.55 stereo cable so the inputs would be reversed.

  6. Sorry to keep making requests, but could you possibly post a youtube video of the SDR in action in a real receive/transmit environment? Counting down the days until my soundcard gets here lol

  7. I replaced my first faulty ERW-7 cable and now I have everything working in SDR mode thanks to the information here on this review and in the comments. I run SDR exclusively with this rig, and it works ok. Interesting note is that the I/Q imbalance is symmetrical in my unit, gain dropoff is severe and noticeable at both ends of the panadapter/waterfall. Annoying, yes but much easier to live with when symmetrical. Here is a YT video of the SDR in action:


    73 de AE5YJ

  8. Hi there just set my dx-dr9e radio up with the erw-7 cable along with two 3.5mm audio cable one into line in and one into speaker output.Is there a certain mic I require for use on my pc ? 3.5mm into mic juck or would a usb version work I have tried a basic electric mic but when I key I get a high pitched squeal I then get a notification up on screen saying out of range using a cheap electret mic pluged into my mic jack on pc.Also is there another similar software which will work with the alnico? apart from kgtrx ? thx

  9. Quick update radio with kgtx working well apart from the tx side when I click on tx I get a nasty squeal and a message saying out of range

    1. From what I understand the mic jack requires a mono plug and a dynamic mic. An electret mic cannot be used as a direct substitute for a dynamic mic without making some wiring or circuitry changes. The electret mic uses phantom power like a condenser mic and if you plug it into a jack that’s intended for a dynamic mic you’ll have a squealing problem or worse.
      Just plug in a simple, unbalanced dynamic mic and you should be good to go. That is, unless the voltage from the electret mic has caused some damage…but I think damage is unlikely with a low voltage electret. Good luck!
      Dub, k4dub

  10. How on earth you program memory channels? If you do what manual says it seems that frequency doesn’t save. Really seem to be overly complicated.

    Mainly now we talk cb-frequencies(receive/transmit same frequency)Mars-mod done to unit.

  11. Mentioned soon after introduction of the DX-SR9T Transceiver was the availability of an optional plug-in “filter board” (Part# EJ-59U) that is still available from ALINCO/REMTRONIX–but has not been mentioned in “factory literature” for well over the last year (2015 & 16). This “filter board” allows the substitution of up to three Eight-Pole COLLINS Mechanical Filters in place of the “stock” Four-Pole MURATA Ceramic Filters. Though not bad to begin with–the improvement in Selectivity is remarkable!! Refer to KZ4B’s comments regarding the DX-SR9T under EHAM.net for much more detail regarding this valuable option.

  12. What a great review, actually it made me purchasing the transceiver. And what can I say? I’m very impressed, what Alinco offers with the DX-SR9, especially considering the relatively low price compared to other TRXs that dont’t offer as many functions, for example FM and the SDR option.

    What I like about the Alinco is the clear and simple design.
    I even don’t mind the three solid power output levels. Where’s the problem? You get a high, low and super-low setting with the possibility to fine-adjust everything on the circuit-board or to limit the high setting to 50 W by soldering a jumper. Working digital modes I set to the “high” level and adjust the output power with the sound level of the PC.

    Ok, what annoys me a bit are the many multifunction buttons at the front, but tell me a similar device that doesn’t have them.

    The KG-TRX software works relatively well but I had to update the TRX to a newer or special firmware to make it work correctly. Otherwise there always was a offset in the waterfall when I changed between LSB/USB/CW mode. I reported to the Alinco online customer service which could help me immediately.

    The Software itself is very basic and clear, what I like very much, because with more options it would tend to be overloaded I guess. Everything works including TX and CW TX.
    The 48 khz is wide enough for me. Ok, there is this signal ghosting but it can be reduced by a high quality soundcard.

    Would I recommend the Alinco? Yes!

    vy 73 DF1FN

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