Using and setting up the Alinco DX-R8T/E receiver as an SDR (software defined radio)

The Alinco DX-R8T (DX-R8E in Europe) can be used as a traditional tabletop or as a software defined receiver

Some time ago, I posted a review of the Alinco DX-R8T–a surprisingly capable, flexible and affordable dedicated tabletop receiver.  In that review, I explored its capabilities as a tabletop unit, and was favorably impressed.

But I knew then that one of the virtues of the DX-R8T is that it’s more than a typical tabletop:  the control head (or, front panel) can literally be detached, and with an extension cable, can be moved as far away as 16 feet from the rest of the receiver. Also, with the optional ERW-7 cable and a shielded audio patch cord, you can connect the Alinco to your PC, converting it to a software-defined radio (SDR).  Just to be fair, I wanted to further check out this alternative operation mode, and review it independently.

I’ve recently had an opportunity to explore the Alinco DX-R8T/E as an SDR, and here’s what I’ve discovered.

As it took some time to figure out how to get KGSDR, the Alinco control software, communicating with my DX-R8T, it’s fair to state that the Alinco’s SDR functionality is not exactly “plug-and-play.”  Nor does Windows seem to find the USB driver automatically.  You must download a USB driver for your computer, as well as download KGSDR from external sites.  It’s also important to note that the Alinco website is not easy to navigate–at least, the relevant links are somewhat buried in large portions of site content.

When I first attempted to set up my receiver as an SDR, I had to use a combination of the printed owner’s manual, the Alinco website, external sites, and simple determination.

Before reviewing the actual performance of the Alinco DX-R8T/E as an SDR, I’ll simplify setting it up as an SDR with a step-by-step process, below. (I wish this was clearly outlined in the owner’s manual, however.)

How to convert your Alinco DX-R8T/E into a Software Defined Receiver

The ERW-7 is the cable that connects your Alinco DX-R8(T) to your computer.

1.) Connect the ERW-7 cable and download the  driver

The ERW-7 is the USB cable that connects your Alinco DX-R8T with your computer. Specifically, it allows your computer to tune and control the DX-R8T; it does not carry audio. If you wish to have full control of your receiver via your PC, you will need to purchase the ERW-7.

You simply plug one end of the cable (the one that looks like an 1/8″ audio connector) in the “clone” port on the back of your Alinco, the other end into an available USB port on your computer.

The download page–at FTDI Chip, the manufacturer of the Alinco cable–has versions of the USB driver for most OS platforms. If you have Windows, you can save a little time by downloading the USB setup tool that will attempt to automatically load the USB driver. Otherwise, you can download and manually install the drivers for the Windows 32 bit version or Windows 64 bit version.

You will need a shielded audio patch cord with 1/8″ stereo plugs on both ends

2.) Connect an audio patch cord

The Alinco DX-R8T/E sends the received IQ signal to your PC via a shielded audio patch cord. This is a standard audio cable that you can purchase at most electronics retailers. It needs to have 1/8″ stereo connectors on both ends, and it must be shielded.

One end of the patch cord is plugged into the IQ port on the back of the receiver, the other is plugged into the microphone input on your computer.

3.) Tell your DX-R8T/E to send the IQ audio to your computer

Your computer will need to “hear” the IQ (spectrum) audio produced by the Alinco DX-R8T/E. The receiver will only send the IQ audio to your computer if you tell it to do so. Fortunately, this is easily done:  simply press the MODE button on the front panel of your receiver until FM appears. Then, simply press the FUNCTION button, then the MODE button.  Your Alinco should now display “IQ” on the main display. You can feel confident the audio is now being sent to your PC.

4.) Install KGSDR

The KGSDR controls are very similar to those of the Ten-Tec RX-320D

KGSDR is a software-defined radio application built specifically for the Alinco DX-R8T/E receivers. A third-party software developer maintains the download page for the KGSDR. Click here to download the setup software for Windows. (If this link doesn’t work, you can also download a zipped copy by clicking here.) To my knowledge, there are no updates to the software–as of time of this post, the current version is 1.0.0.

Installation is simple and only requires that you extract the contents of the zipped folder, then run the KGSDR executable file.

If all has been installed correctly, and the IQ signal is being sent to KGSDR, then you should be able to hear the received audio via your computer.

I have actually installed KGSDR on three different computers. On my laptop, I had to troubleshoot and tweak the settings to get KGSDR to work. On the other two computers, it worked the first time.  All of them were running a 64 bit version of Windows 7.

Troubleshooting tips

If you change the tuned frequency on KGSDR from, say 5,000 kHz to 10,000 kHz, but your Alinco receiver does not change frequencies (it still displays the centered frequency on the front panel), then the USB driver has not been installed or configured properly.

If the receiver tunes, but the audio is garbled or non-existent, you will need to check the audio cord connections. First of all, make sure it’s plugged into the microphone input on your computer (not the speaker/headphone port!) and the IQ port on the back of the Alinco. You cannot plug the patch cord into any other port port on the DX-R8T/E. The plug will fit in the headphone jack, for example, but the IQ port is the only one that sends interpretable analog information to your PC.

Review:  the Alinco DX-R8T/E as an SDR

KGSDR comes with a spectrum and waterfall display (Click to enlarge)

I have read reports of people achieving remarkable results with their Alinco functioning as an SDR…I wish I could report the same.

While the Alinco DX-R8T/E is a very capable tabletop receiver, I find that the SDR functionality adds very little, performance-wise. In fact, in many respects this function seems to compromise the performance of the DX-R8T/E. Still, there are some positives:

Pros

  • Affordable – the EWR-7 USB cable is about $45 US, and you can easily buy a shielded audio patch cable for under $10. For about $55 US, you can unlock the SDR functionality of your receiver.
  • With KGSDR, you can see a bit of the surrounding spectrum on a waterfall display
  • KGSDR is a very lightweight program, not likely to tax even older PCs.
  • KGSDR allows for variable filter control–a true compensating factor since the DX-R8T/E only has a wide/narrow filter on AM (see review)
  • You get the basic benefits of typical SDR receivers:
    • Spectrum/Waterfall display
    • Recording at the push of a button (.wav only)
    • Practically unlimited memory slots
    • With practice, you can import frequency databases
    • A basic DSP filter
  • Simple “lightweight” application that should work on any Windows-based PC (see con)
  • With a DRM decoder, you will be able to receive and decode DRM transmissions (see con)

Cons

  • Performance is underwhelming–not as good as the DX-R8T as a stand-alone tabletop receiver
    • Images of strong stations several kilohertz above the source
    • DX-R8T/E sensitivity is somewhat compromised in SDR mode
    • Selectivity is mediocre
  • Audio patch cord transfers computer/shack RF noise more easily than SDRs which use a digital IQ output via USB
  • Audio fidelity, in general, is not as good as the stand-alone receiver will provide
  • KGSDR has only the most basic of SDR features
  • KGSDR does not allow the spectrum display to be expanded vertically
  • Requires tweaking and repeated efforts in order to function properly
  • Owner’s manual and website are confusing and lack vital information about the installation and trouble-shooting process (hopefully our guide above can help the average user)
  • DRM mode is not native; you will have to use a program like DREAM (see pro)

 Summary

So, is it worth it?  Well, yes––and no.

Yes

If you have $55-60 US dollars to spare, it’s a real bargain. I believe the extra SDR features  and functionality are worth the price. I have not yet tested this in a DXpedition setting, where there are a limited number of RF noise-producing devices around. If you have an RF-“quiet” location in which to use the Alinco as an SDR, you may find you have better results than I describe above.  I imagine you will still suffer from some imaging of stronger signals, however.

Plus, KGSDR is so lightweight, I believe you could use it on a netbook. Moreover, I have heard of owners who’ve actually used other open source SDR applications to drive the Alinco DX-R8T/E.  Additionally, though I have not yet tested it, N4PY makes a software controller that would be far superior to the KGSDR–I base this on the fact that N4PY’s RX-320D software was such an improvement over the standard OEM package.

No

If you wish to enhance the performance (not features) of your Alinco DX-R8T/E, I do not think it’s worth it to put your Alinco into service as an SDR.  Again, I find that it somewhat compromises the performance of what is otherwise an excellent tabletop radio.

If, like me, you have other SDRs in the shack, you’ll find that you’ll seldom use the Alinco as an SDR. Your other digital IQ-based receivers or IF receivers will most likely run circles around it.

Thanks, Alinco

I think it’s pretty cool that for under $500, you can purchase an excellent tabletop receiver like the Alinco DX-R8T/E. Its price tag is significantly lower than its top two competitors (the Icom R75 and Palstar R30A). Still, even with this price edge, Alinco added bonuses like a detachable face plate and SDR functionality, making this a “Swiss Army Knife” of a receiver. So, again,I’ll say…thanks, Alinco!

What do you think?

If you are using the Alinco DX-R8T or E as an SDR and feel you are achieving better performance than I’ve described, or would like to share any other thoughts/suggestions, please comment below. Note that my Alinco is a very early-release–perhaps from the first production run. It is possible that some of the issues I mention above have been resolved  in later production, or that I simply have not finished properly tweaking settings.  I await your responses!

 

Review of the Alinco DX-R8T tabletop shortwave receiver

Last year, when I saw the announcement that a new tabletop radio–the Alinco DX-R8T–was about to hit the market, I almost fell out of my chair.

AlincoDX-R8T

The Alinco DX-R8T tabletop shortwave receiver

A new tabletop on the market? Could it be true? Over the past few years, many long-time manufacturers have dropped out of the shortwave tabletop market, while newer, smaller manufacturers have been popping up in the SDR (Software Defined Radio) market. SDRs are great–a lot of performance for the price–but to listen to the radio, you have to turn on your computer, launch a program, and typically, do things to isolate any noise your computer may generate.

A tabletop, on the other hand, simply requires that you turn it on:  instantly, it’s there, awaiting tuning.

Obviously, I was eager to try out the DX-R8T. Fortunately, the good folks at GRE America (the US distributor for Alinco) kindly loaned me one of their receivers to review for SWLing.com.

First Impressions

The face plate on the Alinco DX-R8T is detachable (with optional extension cable). This view, from underneath, shows where it plugs into the receiver body.

I really appreciate the size and feel of the Alinco DX-R8T.  It’s heavy, with a metal case and a very durable plastic face plate.  It has a bail under the front panel which allows it to be lifted and carried for easy tabletop operation.

Please note: If you’re new to tabletop shortwave receivers or ham radio transceivers, be aware that the Alinco DX-R8T is based on the Alinco DX-SR8T ham radio transceiver–and as such, it operates on 12VDC. Meaning, you will need a 12 volt power supply like the Pyramid PS-3 or similar. If you already have a power supply, make sure it can at least deliver 1.5 amps at 13.8V. You do not want to purchase a “wall wart” type power supply, as many of these are noisy and will effect your ability to hear stations. For the purpose of review, I have actually been running the DX-R8T off of a 40AH, 12 V battery to eliminate all such noise.

The tuning knob on the DX-R8T is solid, smooth and certainly pleased this reviewer.

The tuning knob, which I personally find to be a particularly important feature, is substantial, solid, and moves fluidly–a plus.  I have not found a way to adjust the tension/resistance on the tuning knob, but haven’t felt the need to do so, either. The radio is heavy enough that it stays put while tuning and pressing keys, which is also important.

The ergonomics are good. I like how the volume, squelch, IF shift and RIT are all easily accessible single-function knobs.

If I have any criticism of this radio’s ergonomics, it would simply be that several of the buttons are a bit close to the tuning knob.  I have larger fingers, so while pushing the Function switch, RIT switch, keylock or turning the RIT knob, I often inadvertently move the tuning knob. But in truth, this is a fairly persnickity observation; in general I’m pleased with the panel layout and ergonomics.

AlincoSpeakerLike the IC-R75, the DX-R8T has a front-facing speaker–always a good thing when listening via a built-in speaker. Admittedly, the overall fidelity of the built-in speaker is mediocre at best–it lacks any bass response and sounds shallow, and unfortunately, there’s no way to change the tone from high to low. While the built-in speaker is fine for listening to the ham radio bands (in SSB or a CW mode), I would like better fidelity for the broadcast bands. This is no doubt a vestige of this radio’s ham transceiver heritage.

The front display is large, with an adjustable dimmer. It is crisp and very easy to read, which I like very well.

The competition

The only current shortwave tabletop competitors with the Alinco DX-R8T ($500), are the Icom IC-R75 ($600-700) and the Palstar R30A ($740 US). The Icom IC-R75 is a fine receiver and one I have recommended to many web readers in search of a multi-function tabletop. It has been on the market for years in many versions (some more successful than others), and is generally a solid performer.  The Palstar R30A is also an excellent receiver, though it lacks the bells and whistles of its Japanese counterparts. People who buy a Palstar want bare-bones simplicity and performance.

Since I own a Palstar R30C (the predecessor to the R30A), I used it as a point of comparison in my review of the DX-R8T.

Operation

The DX-R8T is a pleasure to operate. I was able to intuit nearly all but the memory functions without looking at the owner’s manual even once. A major plus, in my opinion!

Tuning is the function you use the most on any radio; with the DX-R8T you have three ways to tune:

  • the tuning knob
  • the up/down arrows and M/kHz button to toggle steps
  • the direct keypad entry
The keypad is configured like that on a phone, which I like. Again, because I have large fingers, I do wish the keypad buttons were slightly bigger. Frequencies are entered in MHz, so to go to 6,925 kHz, for example, you enter “6” “.” “9” “2” “5” “ENT.” To move to 6,000 kHz, you can shortcut by entering “6” “.” “ENT.”  Simple enough.

I did find it helpful to use the up/down arrows to move between meter bands, otherwise I never tune with the up/down arrows.

The tuning knob gets my seal of approval and scanning with it is a pleasure. Admittedly, I wish it were a little more adaptive to tuning speed (i.e., turning quickly speeds up the frequency steps) or that it could be adjusted somewhat. You can tell that the Alinco DX-R8T derives from amateur radio, as its tuning knob speed is perfect for finding ham radio stations.

Switching between modes is simple–pressing the “Mode” button moves you between, AM, FM, CWL, CWU, LSB and USB.

The volume, squelch, IF shift and RIT knobs are all well-spaced and easily accessible.

Broadcast listening

The Alinco DX-R8T is a capable broadcast receiver. In my tests, it was as sensitive as my Palstar.

The generous, wide 9kHz AM bandwidth means that broadcast stations come in with a great deal of fidelity. The flip side of the 9kHz bandwidth, though, is that it is less effective if there is an adjacent station–say, 5kHz away. Luckily, the DX-R8T has an IF shift knob handy so that a modest adjustment can usually eliminate adjacent interference.

I found the narrow AM bandwidth a little too narrow for broadcast listening.  It’s a mere 2 kHz wide and is simply too restrictive if listening to music. For voice intelligibility, the narrow filter works fairly well, using the IF shift to open it a bit. This narrow filter could be useful if trying to snag a weak DX signal, as it’s sufficiently narrow to cut out a lot of noise.

Speaking of noise, the Alinco has a respectfully low noise floor.

Amateur radio bands

The DX-R8T has modes for upper sideband, lower sideband and even upper and lower CW (morse code/digital) sidebands.

It performs rather well on the ham bands, pulling out weak SSB stations from the static.

In fact, its 500 Hz CW audio filter is quite good if you like listening to CW under normal conditions. I did try out the DX-R8T on Field Day 2011 and found that it had a hard time dealing with the intensely crowded band conditions.  Adjacent signals cause “thumping” while listening in pile-ups. This was no surprise; even pricey ham radio transceivers are subject to this type of problem under crowded CW conditions. [I usually turn to my Elecraft K2 or Ten-Tec OMNI VI+ (ham band-only transceivers) when participating in a Field Day or contest event.]

Th DX-R8T should do a formidable job listening to SSB ham radio, utility and pirate radio stations and the digital modes (like PSK31, RTTY, etc.).

Summary

Pros:

  • Excellent sensitivity in the shortwave (HF) bands
  • Simple design requires very little reference to owner’s manual
  • Extra wide 9kHz filter lends to high-fidelity broadcast listening (see con)
  • Filters are effective and well selected for SSB and CW modes
  • Large dimmable back-lit display with all pertinent information
  • Versatile: use the DX-R8T as a tabletop, detach the remote head to save footprint in your shack, mount in your car or connect to your PC and use the DX-R8T as an SDR
  • Front-facing speaker (see con)
  • DRM ready
  • Full control of all receiver functions when used as an SDR
  • Excellent value

Cons:

  • AM narrow filter is a little too narrow for most broadcasts
  • Some front-panel buttons are a little too close to the tuning knob
  • Mediocre built-in speaker, but good fidelity through external speaker or headphones
  • External speaker hook-up only on front panel
  • Does not come with a 12 volt power supply (sold separately)

In the spirit of full disclosure, I have to admit that I was very skeptical of the Alinco DX-R8T before reviewing it. The price point was almost too attractive for a tabletop radio, and to offer the versatility of a detachable faceplate and control as an SDR receiver seemed too good to be true. I thought there must be a compromise somewhere.  Fortunately, it seems I was wrong.

Rear panel view of the Alinco DX-R8T

The Alinco DX-R8T is, in fact, a fine receiver. I especially love the fact that it’s simple to operate. While there are relatively few new tabletops introduced to the market, there are a number of Software Defined Radios available–their performance is excellent, but the learning curve (especially for a newcomer to the hobby) can be intimidating. Plus they require a computer.

With the Alinco DX-R8T, you get the best of both worlds, a simple “turn on and tune in” tabletop, plus a fully DRM ready SDR.

When people write in and ask for advice on buying their first tabletop receiver, I can recommend this DX-R8T without hesitation. Though it lacks the DSP that can be purchased separately with an Icom R75, it’s as sensitive as my Palstar R30C and the 9kHz AM bandwidth lends some excellent fidelity into headphones or an external speaker.

I must admit, I’m impressed with the Alinco DX-R8T.  It has all of the major features I like in a tabletop radio: it’s well-built, easy to use, sensitive, versatile, and it has sufficient control options to help adjust adjacent interference and improve intelligibility. It also has a very attractive price at $499 US.  It’s next-best competitor is probably the Icom R75–but neither the Icom, nor the Palstar R30A, can be used as an SDR and neither have the appropriate IF output for DRM as does the Alinco DX-R8T.  In short, it’s a lot of radio for the money, excellent for those starting in the hobby.

Paired with a good antenna, the Alinco DX-R8T is a bargain performer. If you’ve thought about moving from portable radios to the world of a more serious receiver, you can’t go wrong with the Alinco DX-R8T.

––

Want to hear what audio from the Alinco DX-R8T sounds like? Here is a 2+ hour sampling of Radio New Zealand International recorded 02 Sep 2011:

Resources