Yearly Archives: 2011

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.

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.

Like 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

The Alinco DX-R8T entry in our Shortwave Radio Index which contains more reviews, options for purchasing and technical specifications.
GRE America – US distributor of the Alinco DX-R8T
Universal Radio

DXing with Cumbre show 702

Using exalted carrier reception to tune in pirate radio

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I’ve found that one side benefit of installing a 40 meter delta loop this past weekend is that I now have an antenna which is practically ideal for listening to pirate radio stations in and around the 6925 kHz “watering hole.” So, I’ve been spent a lot of evenings recently listening for pirates with the new antenna.

Shortwave Pirate MAC Shortwave featured DJ Ultraman

But Sunday night was a noisy night on the 40 meter band–I was hearing active static crashes probably associated with hurricane Irene. I did pick up a relatively strong signal from pirate station MAC Shortwave with DJ Ultraman at around 20:40 EST (00:40 UTC)–listen to the end of the broadcast here:

Note that I start the recording using the Alinco DX-R8T, but find the bandwidth too wide (hence the adjacent broadcaster you hear), so I switch to my Palstar R30C. One bonus in this recording: Commander Bunny’s parody of “I Shot the Monkey” originally recorded from WBNY studios.

At the top of the hour I heard Renegade Radio start a broadcast, but the signal was very weak here in the southeastern US. In fact, I couldn’t even ID the station. So, I turned to a trick I’ve used on tabletop and portable shortwave radios alike–namely, Exalted Carrier Reception (ECR) also known as Exalted Carrier Single Sideband (ECSS) reception.

What is ECR or ECSS?

Simply put, it’s when you tune in an AM broadcast using the SSB mode on your radio. In my case, I turned on the USB (upper side band) mode on my Palstar and zero-beat the frequency–meaning, I tuned out the hetrodyne whine until the audio sounded as natural as possible.

This is sort of a “poor man’s version” of synchronous detection (and, frankly, a little inferior to sync detection on most radios). Still, in this case, it made a huge difference in the intelligibility of the broadcast.

Why does it work? Well, as my ham buddy Mike recently explained it:”You are removing any selective fading problems by filtering away one of the sidebands and injecting a carrier of steady amplitude which eliminates the ‘tearing’ heard when a broadcast carrier is varying in amplitude.” Got that?

The Palstar R30 in USB mode tuned to Renegade Radio

At any rate, one of the reasons it works so well on my Palstar is because I can keep the bandwidth set rather wide while listening in SSB, thus helping a bit with the loss of fidelity that happens when moving off of the AM mode. If your radio automatically switches to a narrow filter in SSB mode, the audio fidelity may take a bigger hit, and degrade further.

Though I don’t have a comparison without using the ECR/ECSS method, I can tell you that the AM signal was barely audible. After tuning in using ECR, it became armchair listening.

Listen to almost one hour of Renegade Radio for yourself:

Those of you who have old radios with a very stable variable BFO (beat frequency oscillator) instead of a product detector might try using your BFO tuning to inject the BFO directly over the fading broadcast carrier to accomplish same kind of reception as ECR.

So, next time you have difficulty hearing a weak shortwave station, consider turning on the SSB mode and using the ECR/ECSS method. You may like what you hear! Ahoy, there…

A West Dorset view on the Rampisham Radio Transmitting Station closure

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Photographer: Nigel Mykura. (Creative Commons)

(Source: Real West Dorset)

RAMPISHAM’S radio transmission station may close before Christmas with the loss of more than 20 jobs, even though it’s currently broadcasting into Libya.

The proposed shutdown of the Dorset site follows the BBC’s decision earlier this year to cut back on World Service shortwave broadcasting and stop it altogether by 2014, even though nearly half of the World Service’s audience (184 million in 2010-11) listens via shortwave.

The BBC says it’s phasing out shortwave because the Foreign Office cut the World Service grant by 16% (£46 million).

The author, Jonathan Hudston points out:

Britain has three major sites broadcasting internationally on shortwave. The others are Woofferton in Shropshire and Skelton in Cumbria. Rampisham broadcasts more hours than they do, is more reliable, and has a wider reach across Europe, Africa and the Middle East. (It’s a little-known fact that the National Grid runs right through the Rampisham site, supplying 60,00 volts. I think it has only ever lost power twice in 70 years. Once was during the Great Storm of 1987, which shows it takes something pretty extreme).

He goes on to ask:

Is it really in the UK’s national interests to dismantle Rampisham and sell its equipment for scrap?

The modern preference is said to be for internet-based services, but Jo Glanville, in a good piece about the World Service in the current edition of the London Review of Books, makes the point that shortwave radio can reach many millions of people in ways that internet-based services cannot.

He has a very good point. As we’ve mentioned numerous times before, shortwave radio crosses borders better than any other medium. It’s hard to block and untraceable.

(Read the Full Article Here)

Pirate Radio and Hurricane Irene

Listen to hurricane watch nets on your shortwave radio

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As of time of this posting, Hurricane Irene is on a path that could threaten a large swath of the east coast of the United States. If you have a shortwave radio, even a portable, that can tune in SSB (or Single-Side Band) you can listen to or participate in the Hurricane Watch Net courtesy of your radio.

How to find the Hurricane Watch Net on your portable shortwave radio

Simply tune your radio to 14,325 kHz (or 14.325 MHz). Since these signals are often weaker than AM broadcast signals, you should fully extend your antenna.

Next, turn on the SSB or BFO switch on your radio. These are labeled in various ways, but when you activate the SSB mode, the audio characteristics of your radio will change rather dramatically.

If there is activity on the frequency (i.e., the Watch Net is busy), you should hear voices. More than likely, you will need to tune the SSB to make the voices intelligible. Typically, there will be a dedicated fine tuning knob/wheel to allow you to do this.

Keep in mind that if you hear nothing but static, that may only be because there is no current traffic on the net. Patience will pay off.

Participation

Can you participate in the Hurricane Watch Net and make reports on your weather observations if you’re not a licensed amateur radio operator? Of course! In fact, the Hurricane Watch Net states:

The National Hurricane Center collects observations from people in coastal areas who have home weather stations. Send an e-mail to [email protected] and request information about this program or use their on-line submission form by clicking here.

I will attempt to record some sample audio from the Hurricane Watch Net and post it here (on this page) in the near future.

Also, please note that there are many other frequencies to monitor in the resources section below. Many frequencies are specific to a region, like North Carolina (tune to 3923Khz or 7232Khz SSB), so be sure to try several, not just the HWN.