Category Archives: Shortwave Radio Reviews

A review of the Icom IC-7300 direct RF sampling transceiver

Icom-IC-7300-Front

In August 2015 at the Tokyo Hamfair, Icom debuted a new type of transceiver in their product line––one featuring a direct RF sampling receiver. Essentially, it was an SDR tabletop transceiver.

At about the same time that the IC-7300 started shipping around the world, Icom pulled their venerable IC-7200 off the market. Yet the IC-7200 was established as a well-loved product, due to its highly sensitive receiver, its relatively robust front end, and its quality audio. Moreover, it was simple to operate, which made superb as a Field Day or radio club rig.

Therefore, even though the IC-7300 promised much more versatility than the IC-7200, for its price point it had a tough act to follow.

So, of course––even more so than with any other radio Icom has introduced in the past few years––I was eager to get my hands on a IC-7300.  I’m very fortunate that my good friend, Dave Anderson (K4SV) was one of the first purchasers of the IC-7300, and that he didn’t mind (after only having the rig perhaps one week!) allowing me to borrow it for a several weeks for evaluation.

Note:  I should state here that since this rig was loaned to me, I evaluated it based on the firmware version it shipped with, and made no modifications to it.

Icom-IC-7300-FrontThis review primarily focuses on the receiver’s performance, functionality and usability.

Introducing the Icom IC-7300

In recent years, the “big three” ham radio manufacturers have been using color displays, and––Icom most especially––touch screens. While I’m no fan of backlit touch screens in mobile applications, I  think touch screen displays make a lot of sense in a base radio. If carefully designed, a touch screen can save an operator from heavily-buried menus and decrease the number of multi-function buttons on the front panel.

The challenge, of course, is making a display with intuitive controls, and one that is large enough, and with sufficient resolution, to be useful to the operator. In the past, I’ve been disappointed by many displays; the most successful have been incorporated in DX/Contest-class (i.e., pricier) transceivers, meanwhile, entry-level and mid-priced transceiver displays often seem half-baked. While the graphics may be crisp, spectrum displays at this price point are often too compressed to be useful, and if not a touch display, force the user to pause operation in order to find the correct knob or button to change settings. In such cases, I find myself wondering why the manufacturer went to the expense of a color display at all––?

Icom-IC-7300-Display

But what about the C-7300 display?  I’m thoroughly pleased to report that Icom did a fantastic job of balancing utility and function in design of the IC-7300’s color touch display and front panel. There are  number of ways you can chose to display and arrange elements on the screen–since I’m an SDR fan, I typically chose a display setting which gave the waterfall the most real estate. Of course, one can chose to give the frequency display priority or a number of other arrangements.

User interface

I can tell that Icom built upon their experience with the IC-7100––their first entry-level touch screen display transceiver.

I was able to get the IC-7300 on the air in very little time. Within five minutes of turning on the IC-7300, I was able to:

  • change the display to feature a spectrum waterfall;
  • change the span of the waterfall display;
  • adjust the TX power output;
  • change the filters selection and the transmit mode;
  • change bands and make direct-frequency entries;
  • adjust notch, passband, and filter width;
  • adjust AF and RF gain;
  • set A/B VFOs and operate split;
  • change AGC settings;
  • turn on Noise Reduction/Noise Blanker, and
  • adjust compression.

Basically, I found that all the essential functions are clearly laid out, accessible, and highly functional.  Impressive.

The IC-7300 ships with a manual–– aptly titled, the “Basic” manual––and a CD with the full and unabridged operations manual.  The Basic Manual covers a great deal more than the manual which accompanied the Icom ID-51a, for example. If you read through the manual, you’ll readily familiarize yourself with most of the IC-7300’s higher function operations, and especially, you’ll be able to adjust the settings to your operation style. The Manual is written in simple language, and includes a lot of diagrams and graphics.

If you’re like me, you will find you’ll also need to reference that unabridged manual, so hang on to the CD, too.

Still, I imagine there’s a large percentage of future IC-7300 owners that will never need to reference the manual––especially if they don’t care about tweaking band edges or similar settings. Yes, believe it or not, it’s that easy to use.

Operation

Icom-IC-7300-Function-Buttons

While I spent a great deal of time listening to CW and SSB in various band conditions and at various times of day, I spent less time on the air transmitting.

With that said, all of my transmitting time was in CW since the IC-7300 mic was accidentally left out when my friend loaned me the rig.

I’m please to report that CW operation is quite pleasant. All of the adjustments––RF Power, Key Speed, and CW Pitch––can be quickly modified using the multi-function knob. While in CW mode, you can also toggle full break-in mode, which is quite smooth, via the function button and touch screen.

SSB functions are similar. While in  SSB mode, the multi-function knob allows you to change the tx power, mic gain, and monitor level. The function button opens an on-screen menu with VOX, compression, TBW, and the monitor toggle.

Here’s a short video I made with my phone while I made a few adjustments to the IC-7300:

Of course, my smartphones’s microphone can’t accurately reproduce the audio from the IC-7300, but you probably get the idea.

The only annoyance I noted––and perhaps I’m more sensitive to this, being primarily a QRPer––is that the 7300’s cooling fan starts up each time you key up. It even comes on when transmit power is at its lowest setting. I find this a little distracting in CW.  Fortunately, however, the 7300’s fan is fairly quiet and operates smoothly.

Receiver performance and reader survey results

Since our radio comparison shoot-outs have been particularly popular (and useful; check out our shoot-out between top portables, and ultra-compact radios, and others), I decided it would make sense to invite our informed readership to evaluate the Icom IC-7300’s performance in a series of blind, informal tests. (For information about these surveys, please read the first survey.)

Below, I’ve matched the labels (Radio A/Radio B) with the radio models.  I’ve also included pie charts which show the results from the survey.

Icom IC-7300 vs. WinRadio Excalibur

Weak Signal CW (40 meter band)

Icom IC-7300: Radio A

Audio Player

WinRadio Excalibur: Radio B

Audio Player

CW

Based on listener comments, those of you who preferred the ‘7300 did so because the CW was more interpretable and stable.

Some of you noted that I didn’t quite have CW at the same pitch on both rigs. I believe this is because the IC-7300’s calibration was ever so slightly off. This has since been addressed.

Weak/Strong SSB QSO (40 meter band)

Icom IC-7300: Radio A

Audio Player

WinRadio Excalibur – Radio B

Audio Player

SSB

This result was almost tied. The Excalibur’s audio––without any adjustments––has a fuller and “bassier” sound. The ‘7300 can be adjusted to have similar characteristics, but the default EQ settings produce very flat audio. Many of you commented that the IC-7300 more faithfully produced audio optimized for SSB.


Shortwave Broadcast recordings

The following recordings were made on the 31 meter broadcast band in the evening. Both radios had the same filter width: 9 kHz and 8.2 kHz.

Weak Shortwave AM (Radio Bandeirantes 31 meter band)

Icom IC-7300: Radio A

Audio Player

WinRadio Excalibur – Radio B

Audio Player

Weak-SW-AM

There was a noticeable preference for the WinRadio Excalibur in this particular audio set. Even though the Excalibur’s audio splattered a bit, the content was more interpretable. The IC-7300’s audio sounded flat in comparison––again, something that can be adjusted quite easily in the ‘7300’s audio settings.

Strong Shortwave AM (Radio Romania International, French 31 Meter Band)

Icom IC-7300: Radio A 

Audio Player

WinRadio Excalibur: Radio B

Audio Player

Strong-SW-AM

Once again, the Excalibur won favor, but I imagine results would have been closer had I adjusted the ‘7300’s audio EQ.


Mediumwave Broadcast recordings

Note that the following mediumwave recordings were made during the morning hours (grayline). The strong station is the closest AM broadcaster to my home; it’s not a blow-torch “Class A” type station, merely the closest local broadcaster.

In the “weak” sample, I tuned to 630 kHz where multiple broadcasters could be heard on frequency, but one was dominant.

Both radios are set to a filter width of 9.0 kHz.

Strong Mediumwave AM (1010 kHz)

Icom IC-7300: Radio A

Audio Player

WinRadio Excalibur: Radio B

Audio Player

Strong-MW-AM

Two out of three listeners preferred the Excalibur in this example.

Weak Mediumwave AM (630 kHz)

Icom IC-7300: Radio A

Audio Player

WinRadio Excalibur – Radio B

Audio Player

Weak-MW-AM

In this particular example, the IC-7300 could not pull the strongest broadcaster out of the pile as well as the WinRadio Excalibur. In fairness, the Excalibur was using AM sync detection, something the IC-7300 lacks.

Icom IC-7300 vs. Elecraft KX3

IMG_20160424_105444629

I also decided to pit the IC-7300 against my well-loved Elecraft KX3.


Audio Clip 1: CW (20 meter band)

Elecraft KX3: Radio A

Audio Player

Icom IC-7300: Radio B

Audio Player

Elecraft - CW

Based on comments, readers who preferred the IC-7300 felt the CW sounded more pleasant and stable.


Audio Clip 2: Weak Signal CW (20 meter band)

Elecraft KX3: Radio A

Audio Player

Icom IC-7300: Rado B

Audio Player

Elecraft - WeakCW

Your comments indicated that the CW seemed to “pop out” of the noise slightly better with the IC-7300.


Audio Clip 3: Weak/Strong SSB
(Sable Island working Asia/Pacific on 20 meter band)

Icom IC-7300: Radio A

Audio Player

Elecraft KX3: Radio B

Audio Player

Elecraft SSB

These results were spilt in the middle. Again, I believe this comes down to personal preference in the audio. And again––in both radios––the audio EQ can be adjusted to suit the operator.


Receiver performance summary

I enjoy producing audio clips for readers to compare and comment upon. Each time I’ve done so in the past, I’ve had listeners argue the virtues of a particular audio clip while others have the complete opposite reaction to that same clip. Not all of us prefer our audio served up in the same way. No doubt, there’s a great deal of subjectivity in this sort of test.

I’ve had the IC-7300 on the air every day since I took possession of it. I’ve listened to SSB, CW, and lots of AM/SW broadcasters.

And here’s my summary: the IC-7300 is an excellent receiver. It has a low noise floor, superb sensitivity and excellent selectivity. I even slightly prefer its audio to that of my Elecraft KX3, and I’m a huge fan of the little KX3.

I’ve written before about how difficult it is to compare SDRs; the problem is that there are so many ways to tweak your audio, filters, AGC, noise reduction, etc. that it’s hard to compare apples with apples.

In the audio samples above, the IC-7300 and WinRadio Excalibur were both set to their default audio settings. In SSB and CW, the IC-7300 excels, in my opinion. CW seems to pop out of the noise better and SSB is more pleasant and interpretable. The Excalibur has a better audio profile for AM broadcasters, though. Its default audio simply sounds fuller–more robust.

The audio from the IC-7300 on AM sounded absolutely flat. However, if I tweak the audio of the ‘7300, adding more bass, it instantly sounds more like a dedicated tabletop receiver.

Here’s a recent example of Radio Romania International:

Audio Player

I should also mention that while the IC-7300’s built-in digital recording is a fantastic and effective feature, it doesn’t produce audio true to what’s heard through headphones live. This is especially the case when you add more bass and treble response as in the RRI example above. When the audio EQ is set to a default flat, it’s quite accurate.

To be clear:  for broadcast listening, I’ll still reach for my SDRs (the Excalibur, FDM-S2, TitanSDR and CR-1a).

If, however, I have limited space and/or budget for multiple receivers, I’d be quite happy using the IC-7300 as a broadcast receiver on the HF bands.

Speaking from the Shortwave Radio Listener (SWL) perspective, meanwhile, am I pleased with how the ‘7300 handles the broadcast bands?  Most definitely.

And as a ham radio operator, am I pleased with the IC-7300’s receiver––?  Absolutely.

In short:  the IC-7300 seems to have some of the best all-around receiver qualities of any transceiver I know under $2,000.

Summary

Every radio has its pros and cons. When I begin a review of a radio, I take notes of my initial impressions. Here’s my list for the IC-7300:

Pros

  • Excellent sensitivity and selectivity
  • Excellent, highly-customizable RX and TX audio
  • Color touch screen interface
    • Spectrum display is large enough to be useful
    • Intuitive functions
  • Twin PBT is both intuitive to operate and effective
  • Effective RF gain to compensate for noisy band conditions
  • Built-in RX and TX recording, file transfers via common SD card
  • Front panel knobs and buttons are spaced appropriately and easy to use
  • Quiet cooling fan (see con)
  • Decodes RTTY on screen
  • Built-in ATU
  • Antenna analyzer function (not tested)

Cons

  • Lacks secondary receive antenna jack on rear panel
  • Cooling fan immediately starts up on CW/SSB transmit at any power setting (see pro regarding fan noise)
  • Occasionally you may get lost in deeper customized functions
  • Supplied printed basic owner’s manual, while well-written, doesn’t fully cover the IC-7300s functions and options; you must explore the digital owner’s manual in supplied CD.

Conclusion

In a nutshell: Icom has hit a home run with the IC-7300.  If I didn’t already have an Elecraft KX3 and K2, I would buy the IC-7300 without hesitation.

Though the price point is a little high for an “entry level transceiver,” it’s worth every penny, in my opinion. For $1500 US, you get a fantastic general-coverage transceiver with an intuitive interface, nearly every function you can imagine, and performance that would please even a seasoned DXer.

Though I haven’t done and A/B comparison with the IC-7200, I imagine the IC-7300 would prevail in a test. The IC-7300 would certainly wipe the floor with it’s more economical brother, the IC-718.

Radio clubs, take note:

In my view, the IC-7300 has the makings of an excellent radio club rig in which performance, functionality, as well as ease of use are important. I expect that the IC-7300 will not only cope very well with crowded and crazy Field Day conditions, but it will also give any newcomers to the hobby a little experience with a proper modern transceiver. The fact that you can view signals so easily on the spectrum display means that it will be easier to chase contacts and monitor bands as they open and close. Indeed, what better way to mentor a newly-minted ham in modes, contacts, carriers, QRN, QRM, and so forth, than to simply point these out on the IC-7300’s bright, clear display––?

If your club is considering a transceiver upgrade or purchase, do seriously consider the IC-7300. I think you’ll find this rig is up to the task.

And for home? The Icom IC-7300 may be all of the rig you’ll ever need.

Luke considers the Panasonic RF-9000 an investment and solid performer

Panasonic-RF-9000

In response to our post about a Panasonic RF-9000 being offered on eBay for $20,000(!), SWLing Post reader, Luke, comments:

I actually just bought a RF-9000 from a Spanish Ebay seller. It might show up in the ‘completed auctions’, not sure. I made an offer of 2,000 Euros and he accepted. Of course I am like most of you who might have seen one in a magazine or book for over 20 years, but never dreamed of actually owning one.

My unit had a few imperfections like a couple of dings and the grille was not 100% with some slight discoloration but I cleaned it up nicely and got some Testors paint to fill in the dings. It came with the cover but with no documentation. Everything works perfectly and there are no dirty or inoperable switches or buttons. Even the lights all work which is a relief.

I can only really compare it to the Sony ICF-2010 and the Satellit 700, both of which I have owned at one time. I still have the Sony. The Panasonic is on a much different level as far as ease of use. And the tuning is super fast with absolutely no audio lag between channels if that is the right description. It is really smooth sailing all the way across the dial and you can go straight from FM into the LW band which is pretty cool.

Another nice feature is the band selection buttons actually have the corresponding frequencies also so there is no guesswork. The odd thing about the unit is that all of those cool buttons that you see pertain mainly to the clock and timer functions.

The shortwave side is fairly stripped down with just a 3-way bandwidth selector, a switch for a noise blanker, a RF gain knob, and a 4 position switch for USB, LSB, etc. That is pretty much it for tuning and knob twiddling and I would had preferred to have a few more knobs for antenna trim and other features to eek out faint signals. I guess I was expecting more I don’t know?

I personally find it to be the best radio I have ever used as far as audio and ease of use. I did some side by side tests against the ICF-2010 for sensitivity and it is about a wash. But for 1/10 the price the Sony wins all day long and you cant beat the sync detector! I find myself amazed that I would ever own a RF-9000 and consider it a great investment. I think this seller is dreaming if he thinks he can get that price for it though.

Thanks for sharing your review of the RF-9000! You certainly have a rare and classy receiver that actually performs–a keeper for sure. If I recall correctly, even the tuning knob feels perfectly weighted on the ‘9000.

Based on what these sell for, I don’t think you overpaid for your ‘9000–indeed, you got it at a bit of a discount.

Click here to search eBay for the Panasonic RF-9000.

Click here to view the RF-9000 at Universal Radio.

Steven is impressed with the CountyComm GP5/SSB and high-gain bar antenna

GP5SSB-Front

Many thanks to SWLing Post contributor, Steven Crawford, who sent the following message to me (several weeks ago) and has kindly allowed me to share it here. Steven writes:

I hope this finds you and yours well. I just wanted to take a few moments and express my sincere thanks to you for your posts of 12/20/2014 and 1/6/2016, and for sharing Larry Thompson’s post of 2/28/2016, and Ron’s post of 1/16/2016. If you are in regular contact with the other individuals please feel free to pass along my thanks as each of you and the respective post convinced me to purchase a CountyComm GP5/SSB and Ebay seller playloudfm’s high-gain ferrite bar antenna. I am so glad I did, so a hearty Thank You to each of you.

The afternoon of March 19th local was the first chance I had to use my GP-5/SSB. After popping in three fresh AA’s on AM using the internal ferrite bar antenna Beaumont, Texas’ own powerhouse 5,000 watt KLVI 560 was there as was 1,000 watt Orange’s KOGT 1600, 23 miles away and my AM daytime benchmark 50 kW KTRH 740 Houston 70 or so miles away on the back side of their pattern. KTRH surprisingly can be a little difficult during the day due to noise. The surprise was 50 kW WWL New Orleans 240 miles away was intelligible above the background noise. Extending the whip a quickie SW test showed WWV Fort Collins time signal was present at 15 MHz.

On the AM side the real money lay after dark once the sun had set in Beaumont and San Antonio. Using only the internal ferrite bar antenna all of the aforementioned AM stations were present. Continuing the internal antenna’s test 50 kW WBAP 820 Dallas 244 miles away and 50kW WOAI 1200 San Antonio 266 miles away were present. I started grinning when 50 kW WLAC 1510 Nashville 598 miles away and 50kW KMOX 1120 St. Louis 632 miles away were just intelligible above the background noise. Keep in mind these stations were received using only the internal antenna.

GP5SSB-MW-Antenna-1

I popped the CountyComm included factory external ferrite bar on and used it 9 -10 PM Saturday local, 0200 – 0300 March 20 UTC. Using the external antenna rotated for best reception WLAC and KMOX improved to the point they were easily listenable. 50 kW WSB 750 Atlanta 625 miles away was listenable above the noise and most surprising 50kW WBBM 780 Chicago 892 miles away(!!!) was just intelligible above the background noise. Another quickie SW test was performed at 10 PM local, 0300 March 20 Sunday UTC by extending the built in whip and the WWV Fort Collins time signals were present at 5 and 10 MHz with 10MHz being particularly well received.

Ferrite-Bar-Antenna-PL-365-GP5SSB

Photo source: eBay

A real treat lay in store after receiving Ebay seller playloudfm’s aftermarket high-gain ferrite bar antenna, the subject of your 1/6/2016 and Ron’s 1/16/2016 post, yesterday. I am not experienced enough to judge what the space weather or propagation conditions were like from 0300 to 0400 March 27th UTC but I was extremely surprised and pleased with the reception results the new antenna afforded.

As I sat relaxing in my easy chair before bed I decided to try the combo out using the included earphones so as to not wake my wife. With the lights off and my iPad open to www.oldradio.com/archives/stations/ccs.htm to help identify clear channel stations I took the handheld combo for a spin. All of the stations found with the factory supplied external ferrite bar antenna were present. There was just so much more signal present using the aftermarket antenna each became easily listenable. For WOAI, WWL, WLAC and KMOX the effect was as if I was located within their local night coverage area. 50 kW WHAS Louisville Kentucky 740 miles away was newly found present. Chicago’s WBBM was there as before and I was surprised to find 50 kW WGN 720 Chicago as well. The reception quality was such that one could enjoy listening to a Cub’s game or breaking local news story should one be so inclined on WBBM or WGN. The listening experience was similar for newly found 50 kW XEROK 800 Ciudad Juarez 738 miles away.

The most surprising and gratifying, to me anyway, find of the night using playloudfm’s antenna was receiving 5,000 watt (nights!) KCMO 710 Kansas City Missouri 624 miles away. The ability to rotate the antenna to take advantage of it’s directional and nulling ability really aided in this reception. It really is a great benefit to be able to rotate the GP-5/SSB’s external AM antennas for peak signal strength while nulling interfering signals and noise. Indeed KCMO was missing in one antenna orientation but rotating the antenna 90 degrees and the station popped in. I really should have jotted signal strength to noise ratios down but I was just enjoying tuning through the spectrum too much. I have not fully tested SSB Exalted Carrier tuning on the GP5/SSB of difficult stations but have tried it 3 or 4 times and it does appear to work as does tuning 1 kHZ either side of the nominal frequency. The later technique did help clean up some signals by further reducing background noise without greatly affecting listenability.

As best I can tell I ordered and received either the last or next to last of playloudfm’s current batch of high-gain ferrite bar antennas as the Ebay add showed two available when I ordered and the ad was almost immediately replaced with an “accepting pre-orders” ad. Currently there are no ads by seller playloudfm.[Note: it appears more inventory has been added to eBay.] My transaction and shipping was quick and smooth. The bulk of the two week wait occurred after the package was received at the Athens airport where tracking stopped. It should be noted by buyers should more antennas become available the tracking number supplied does not work on the USPS tracking service but it will track the package to Athens through Greece’s Hellenic Post tracking service at http://www.elta.gr/en-us/personal/tracktrace.aspx

Note: all distances listed above are “as the crow flies”, straight line city center to city center and are not necessarily correct for the transmission tower location.

This little radio is fast becoming a hand holdable favorite with easy to learn button placement for use in the dark. I am all ready beginning to prefer it to my Sony SW7600GR / AN200 loop combo for MW broadcast AM reception but I really must do more work with SW before calling the CountyComm my favorite of the two.

Steven followed up a week or so later with this addendum to his review:

I finally got the opportunity to test the FM performance of the radio using only the extended whip on the afternoon of April 1st, April 1st 19:30 – 21:00 UTC. Using www.radio-locator.com and my zip code I found 51 FM stations listed as local, distant and possible fringe reception. I was very surprised and pleased when I was able to log all of the most distant fringe stations, KUHF, KKBQ, KTBZ, KKHH, KHMX, KBXX, KODA, KILT, KLOL, KMJQ, KRBE, KOVE, and KGLK, with ERP’s listed as 90 to 100 kW and distances in the given in the 80 to 90 mile range. In short I was able to log all 51 listed stations. The FM broadcast band is crowded indeed with this little rocket radio. It should be noted my little corner of Southeast Texas is dead flat with nothing between me and these stations broadcast towers but Houston skyscrapers, the typical urban / suburban sprawl, timber and marsh. Ground elevations range from 16 ft to 80 ft above sea level between me and many of the broadcast towers.

[…]My Sony SW7600GR / AN200 loop / Sony AN-LP1 loop combination sits in it’s go bag rapidly falling into disfavor, replaced by the easily used in the dark one handed CountyComm GP-5/SSB. Again thank you for your kind response and thanks again to all who motivated me to purchase this rig.

Steven, thank you so much for taking the time to share your experience with the GP5-SSB and the high-gain ferrite bar antenna.

I also have the high-gain ferrite bar antenna and have been meaning to post videos showing how it performs compared with the supplied GP5 antenna. I must say, it does do a pretty amazing job. I’ll get some videos posted in the coming weeks!

Mike’s overview and review of the $40 Soft66RTL3 SDR by Kazunori Miura (JA7TDO)

RTL3

Many thanks to SWLing Post contributor, Mike Ladd, for the following guest post and overview of setting up and using the Soft66RTL3 SDR:


Soft66RTL3 SDR: A low cost…Good performer direct from Japan

by Mike Ladd

Much has changed in the last 8 years in the world of SDR radios. Fast forward to 2016 and just about everyone in the hobby has heard the buzz word “SDR radio”. When SDRs first came out to the market they were all aimed at HF listening and you had two types to pick from. The first being soundcard based and the second being direct sampling. The price gap between the two were several hundred dollars. The more expensive being direct sampling. As the hobby progressed, so did the technology and the prices started to shift dramatically.

You can now purchase a TV dongle for $10.00 and turn it into a SDR. The Soft66RTL3 is basically a TV dongle but with a lot more features.

The Soft66RTL3 comes from an engineer who is no stranger to the world of SDRS. Kazunori Miura (JA7TDO) has been designing and selling many models of SDRS over the internet and shipping them direct from Japan for about 7 years. The Soft66RTL3 is his latest of model hot off his bench. This SDR is a dual input RTL-SDR with a built in 50 MHz upconverter along with 4 user selectable band pass filters that greatly increase your signal to noise ratio in the HF bands.

Soft66RTL3-board-001 Soft66RTL3-Board 2 Soft66RTL3-board

The frequency range of the RTL3 is from DC to Daylight (0.4 kHz to 1.7 GHz). Miura also addressed a heat issue with the previous version (RTL2) by adding a thermal pad and heatsink. RTL dongles are notoriously unstable due to overheating. In theory, the thermal pad should add frequency stability and keep drift to a minimal.

RTL3-TrimmerPot

The last feature of the RTL3 is the input gain trimmer pot (see image above). The trimmer pot is for the HF side of the SDR and is already set before it’s shipped from Japan. If you would like to reduce or increase it the trimmer pot is easily accessible. I would suggest leaving it as is.

The RTL3 is broken down into two sections: the HF input side and the VHF/UHF input side.

Soft66RTL3-encoder

The HF side of the SDR (above) has a red rotary encoder and trimmer pot port. The VHF/UHF side (below) has the USB Mini-B connection.

Soft66RTL3-back

Both sides of the RTL3 terminate to a SMA-Male connection and Power comes from a single USB Mini-B cable.

Soft66RTL3-BandPassFilter

Band pass filter selection

If you look at the rotary encoder (red cap cover) you will see a small notch window. The 12 o’clock position is #5 on the encoder dial. One click clockwise will take you to switch position #6 and one click counterclockwise will take you to #4. You should pull the red cap cover off to have a look and get your bearings.

The band pass filter selection is as follows:

  • #4 enables BPF 0.4 to 1.2MHz
  • #5 enables BPF 1.2MHz to 5MHz
  • #6 enables BPF 5MHz to 15MHz
  • #7 enables BPF 15MHz to 30MHz
  • #8 or #9 enables the VHF UHF side of the SDR

All other positions will bypass the filtering section on the HF side of the SDR.

Installation

If you already have a RTL-SDR on your system then all you need to do is swap it out with the RTL3 and change the offset of -50,000,000 in HDSDR or SDR# to listen to the HF side of the RTL3–but if this is your first SDR we will need to install 2 items: the front end app and the driver.

I will assume your system is Win-7 or better and we will be using SDR# as our program of choice to drive the RTL3. The RTL3 runs just fine in HDSDR and SDR-Console, but by choosing SDR# it will reduce our setup time considerably.

ScreenShot-SDR

  1. Plug in the RTL3
  2. Make a folder on your desktop and name it SDR#
  3. Download the latest version SDR# from www.airspy.com and copy the contents of the zip file to your newly created SDR# folder
  4. Inside of your SDR# folder, double click on install-rtlsdr
  5. After the batch completes, double click on the “zadig.exe” inside your SDR# folder

screengrab

When you run the “zadig.exe” make sure you select “list all devices” as shown above.

ScreenGrab-Window

The next 3 steps are:

  1. Select “Bulk-In Interface” (Interface 0)
  2. Make sure the proper USB device is selected (2838)
  3. Click “install driver”

The RTL3 is now ready to be used and no further setup is required.

For a more detailed installation I would visit RTL-SDR.COM for a complete setup instructions: http://www.rtl-sdr.com/rtl-sdr-quick-start-guide

I will assume you did not have any issues setting up the ZADIG driver and now move on to using the RTL3 inside of SDR#. I will show you real world conditions that are not from any scientific standpoint.

Antenna wise, for the HF side I will be using a G5RV mini and for the VHF/UHF side I will be using a Scanntenna ST-2.

You can now launch SDR# and check the following settings (see image below).

SDRSharp-Settings

For the VHF/UHF side of the RTL3 you will want the rotary encoder on position #9. You want the cutout in the encoder cap showing the 5 o’clock position.

Summary

I have been using this SDR for a little over 3 months. Out of all the low cost SDR’S on the market, this one gives you the most bang-for-your-buck and it is a great entry level SDR with some “Pro” features.

Pros:

  • Low Price
  • HF VHF/UHF in one package
  • Works with any app that supports the RTL-SDR front end
  • 4 user selectable band pass filters for HF
  • Highly sensitive user controlled input RF amp
  • Small & very compact metal case
  • Dual input SMA jacks
  • ESD protection diode

Cons

  • Some intermod in the 460-470 MHz range
  • Inputs are on opposite sides of the SDR body

The Soft66RTL3 price is $40.00 US shipped–click here to order.


Mike, thank you so much for this excellent overview of the Soft66RTL3!  I’m especially appreciative of the time you’ve taken to explain the installation process–for many, this is one of the more difficult RTL-SDR learning curves.

I’m very tempted to check this out for myself–I love the fact that this little SDR has bandpass filters.

Post Readers: I suspect Mike will monitor the comments in this post, so feel free to ask questions. Make sure to check out Mike’s website, where you’ll find more articles about software defined radios.

The CountyComm GP5/SSB: my go-to shortwave radio for hiking

CountyComm GP5/SSB while hiking

My two hiking companions: the CountyComm GP5/SSB and Hazel the dog.

Posting the Blinq deal a few moments ago reminded me that my favorite shortwave radio to use while hiking/walking is the CountyComm GP5/SSB.

I have CountyComm’s custom GP5 case which I clip to my belt or backpack. While hiking, I find it handy to open the case from the top, pull the radio out and operate/tune it with only one hand. Indeed, the vertical form factor of the GP5/SSB is ergonomically-ideal; I can control almost all of the radio functions without having to use two hands. A huge bonus while hiking on uneven terrain!

Typically, when I start a hike, I enable an EMT scan and within a minute or so, the GP5/SSB populates temporary memory positions with all of the signals it can easily receive. When you’re in the middle of the woods–far from sources of radio interference–you’ll be amazed by what you can hear.

GP5SSB-Top

Of course, with the antenna fully extended, one does have to watch out for low-hanging branches, etc.

CountyComm GP5/SSB while hiking

Since the telescoping antenna doesn’t swivel, it’s much easier to hold the radio in a way that the antenna points forward while you hike (bonus: it’ll catch all of the spider webs across the trail before your face does!).

GP5SSB-MW-Antenna

So far, I’ve never used the external mediumwave ferrite bar antenna while hiking–I worry that I could drop the radio and damage either the antenna or the 1/8″ antenna jack.

I typically listen to the GP5 with headphones unless I’m walking a trail during the time of year when black bears are active (in which case the speaker helps alert bears that I’m in the neighborhood).

GP5SSB-Front

Of course, there are a few other radio models with an identical vertical form-factor–most notably, the:

If you’re not familiar with the CountyComm GP5/SSB, click here to read previous posts. I also featured the CountyComm GP5/DSP (Tecsun PL-360) in an ultra portable shoot out in 2014–click here to read.

Do you have a favorite shortwave portable for hiking, biking or cycling? Please comment!

Larry’s review of the CountyComm GP5/SSB

Many thanks to SWLing Post reader, Larry Thompson, who shares his review of the CountyComm GP5/SSB:


GP5SSB-Front

Been having a ton of fun with my new toy, the tiny survivalist radio, the CountyComm GP5/SSB receiver. $74.95 with free heavy duty cordura case with metal belt clip (normally $17.95). Also purchased 2 spare whip antennas @ $6.00 ea. The unit arrived promptly
in just 5 days from CA.

The radio is manufactured by Tecsun and is similar to the Tecsun PL-365, but re-engineer end to military standards for use in embassies and military installations around the world. The case is a heavy plastic that feels like anodized aluminum.

It’s about the size of a small TV remote control, taller than a cell phone, and about 1/2 the width of an iPhone.

Very, east intuitive menus. Incredibly sensitive to dx, relatively good selectivity. A great radio to throw in your travel bag or briefcase. So small that no one, especially customs, TSA, etc would even suspect it is a shortwave receiver with SSB capabilities.
I live in a very highly QRM and RFI interference zone.

I’m in the central city, in an old 1920’s hi-rise, with high power tension lines right next to the building.

Lots of QRM from the elevator motors, etc. Having a good antenna option is a challenge.
I’ve resorted to a stealth longwire antenna, strung out my 5th floor window. It’s 50′ of #16 black insulated copper stranded wire, weighted by a medium size galvanized carriage nut. It seems to work well.

I also use a Magic Wand shortwave antenna, a type of broomstick antenna with 23′ of lead-in, available from Lowbander on eBay.

My main receivers have been a Sony ICF-SW7600GR dual conversion receiver and the SRDPlay. In the past, I have listened to dx with some really outstanding receivers, including a Nordmende Globetrotter, a National NC-183D, a Japan Radio JRC-525′ and a Yaesu FT900AT transceiver. The later two were computer-controlled using TRX-Manager software.

In just 4 days, I can’t get over the sensitivity of the CountyComm GP-5/SSB and it’s ability to pull in stations. So far, it’s far superior to the Sony or SDRPlay.

Digging into the specs, it is a direct conversion receiver, using a DSP si47XX microchip from Silicon Labs to digitize the analog AM/FM broadcasting signal base on modern software technology and radio principles. The direct conversion circuitry can highly improve a radio’s sensitivity, selectivity, S/N ratio and anti-interference capabilities. Direct conversion using software is far superior to a double or triple conversion traditional IF circuitry. This must explain why the unit is so amazingly sensitive!

I can hear things on this unit that I can’t even begin to hear on the Sony or the SDRPlay. The FM reception and sound with earphones is amazing and LW and AM reception is equally sensitive. I can easily get WLW Cincinnati 700 kHz in the daytime here in St. Louis!

There are 550 preset memories: 100 for AM, 100 for FM, 100 for SSB, and 250 for SW. You can scan the memories or scan the bands in various ways. You can also use the Auto Tune Storage function to store memories.

Something I really enjoy is the Easy Tuning Mode function. The ETM function allows you to tune into stations easily and temporarily store them into the ETM storage. 100 stations for FM/MW and 250 for SW. Scanned stations will not be stored in the regular 550 memories, but will remain in the ETM temporary storage until the next time you do an ETM scan.

This is a great feature for travel. When you are in a different city, you can perform the ETS function and this will not delete any of the stations already in the memory.


Thanks for sharing your review, Larry. I use the GP5/SSB all of the time–it stays in one of my vehicles and I often use it for walks, picnics, camping and even a little parking lot DXing.

I suspect if your SDRplay RSP was hooked up to an antenna that could better mitigate your local QRM, you’d find it outperforms the GP5/SSB. The great thing about portables, though, is that you can simply take them to areas with low noise levels. It’s just a matter of finding the right location!

The CountyComm GP5/SSB is a very handy portable. Thanks again! 

The CountyComm GP5/SSB can be purchased from:

The Tecsun version, the PL-365, can be purchased on eBay (though be aware that some sellers have BuyItNow prices almost two times the price of CountyComm).

Review of the Kaito KA108

Kaito-KA108-Front-2

Recently, I learned about a new portable by Kaito Electronics: the Kaito KA108. While there are a number of compact portables on the market, the KA108 really caught my attention because it features a built-in digital recorder. Which is to say, you can listen to a station on shortwave, press a button, and the KA108 will record it to a MicroSD card. Pretty cool, right? It’s also the first shortwave portable I’ve ever known that offers a scheduling feature for recordings.

In the past there have been a few shortwave portables with digital recording capabilities, but most of these have been plagued with poor performance. So this time, I had my fingers crossed that Kaito might have produced a winner.

Having used the KA108 for several days now, my initial review follows, with a focus on shortwave as well as mediumwave performance.

User’s Manual

The KA108 actually ships with two manuals: a quick start reference guide and a proper highly-detailed user’s manual.

Kaito-KA108-Unboxing-3

The manual is written in English and is quite descriptive, despite a number of spelling and grammar errors that should have been caught before going to print. It’s obvious that Kaito didn’t hire a native English speaker/professional editor to check their copy.  (I don’t understand why a company would go to the expense to produce a manual without having it professionally edited…Kaito, please take note!)  Fortunately, these spelling and grammar errors, while annoying, can be overlooked and/or deciphered by most English-speaking readers.

Tuning

Kaito-KA108-Side3

On the plus side, the KA108 sports a full number keypad for direct frequency entry. This makes tuning to a known frequency a very simple process––with one exception (see below). There’s also a tuning wheel on the right side of the radio.

Kaito-KA108-Keypad

Note where the “0” is placed on the keypad: why the change?

Using the keypad requires some getting used to, however. Most of us––myself included––are familiar with traditional numeric keypads, but the KA108 inexplicably changes the game plan: as you can see above, the “0” button is located on the lower right side of the main keypad. So it took me a few hours of use before I could reliably key in a frequency without looking at the radio.

In my humble opinion, Kaito should have moved the number pad up one row, positioned the “ATS” button to the lowest row on the left, the “0” button to its immediate right, and completed the bottom row with the “Rewind/Play/Fast-Forward” buttons.

Another annoyance––and this is a big one for me–-is that the KA108 has extended muting between frequency changes. It makes band-scanning a frustrating experience. I made a short video demonstrating this:

Audio

DSC_3495The KA108 is designed around a very innovative small speaker with an acoustic chamber that significantly boosts bass response. This is the same speaker used in the Melson S8 that I reviewed some time ago.

The audio fidelity is excellent on FM, and when playing back a full-fidelity digital recording. Unfortunately, when tuned to the AM broadcast (mediumwave) band or to the shortwave bands, the KA108 falls short; the bass response actually becomes an impediment to listening.

In a nutshell: the KA108 audio has issues. A further explanation of the KA108’s audio is described in the performance notes that follow.

FM Performance

On a positive note, the Kaito KA108 has respectable FM reception. I was able to receive all my benchmark FM stations with little trouble, and the KA108 maintained a strong lock on all signals.

And as mentioned above, KA108 audio via the built-in speaker is much better on FM than on any other band. Indeed, on FM, the KA108 produces rich, full-fidelity audio that can easily fill a room. Audio is similar to that of the Melson M7 and the Melson S8.

If you’re seeking a nice FM portable with robust audio, you’ll enjoy the KA108.

Shortwave Performance

Kaito-KA-108

I’m quite disappointed with the KA108’s shortwave performance.

Almost immediately after unboxing the KA108, I inserted a battery, walked outdoors, and tuned through the 31 meter band.

Other than a couple of blow-torch North American private broadcasters, I heard…nothing. It was during this first band scan that I realized how annoying the tuning mute could be. And the audio, meanwhile, sounded muffled and garbled: I assumed that there was some local interference, and simply turned the radio off, hoping the following day would produce a change for the better.

The following day, I spent a great deal of time with the KA108 on the air, and compared it with the Eton Traveller III and the Tecsun PL-310ET––both capable, similarly-priced compact DSP radios.

Sure enough, when compared with other portables, the KA108’s reception is, sadly, rather poor.

At first I thought it might be an issue with receiver sensitivity, but the KA108 could receive almost every station the Traveller III and the PL-310ET could receive. But the audio was so muffled on the KA108, even with  the use of headphones, that spoken word was hard to interpret. Additionally, the over-active AGC (Automatic Gain Control) meant that audio levels were all over the place. That combination makes for fatiguing listening.

Volume level indicator.

Volume level indicator.

Over the next few days with the KA108 on shortwave, I drew a few conclusions.

After recognizing that the audio fidelity did not improve significantly when using headphones, I realized that at least three factors are having a negative impact on shortwave audio, as follows:

  1. The default AM bandwidth is too narrow for broadcasts, and cannot be adjusted
  2. The AGC setting is over-active and causes audio pumping; it, too, cannot be adjusted
  3.  Portions of the shortwave bands are polluted by internally-generated noise/interference

This combination makes for sloppy shortwave performance.

To save time in making the KA108’s comparison information readily available, as well as to indicate actual speaker performance, I decided to take a few quick comparison videos not with the KA108 or an external mic but simply with my smartphone. While my phone’s microphone is somewhat limited, I believe you’ll be able to observe the  inherent problems with the KA108.

I compared the KA108 with the Traveller III in each video.

In the first comparison, I tuned to Radio Exterior De España on 9690 kHz, as you’ll see. The signal was marginal or relatively weak at the time:

(Click here to view the video on YouTube.)

Next, I tuned in a very strong shortwave signal from Radio Havana Cuba on 11,670 kHz:

(Click here to view on YouTube.)

Finally, later in the afternoon, I tuned to All India Radio on 9,445 kHz––again, a marginal signal:

(Click here to view this video on YouTube.)

Mediumwave Performance

Mediumwave (a.k.a., AM broadcast band) performance is very similar to shortwave performance.

In this video, I’ve tuned to an AM station located twenty-five miles away on 1600 kHz.  The KA108 can receive the station, but audio is not pleasant and the AGC is, yet again, overactive. I’ve noticed that the mediumwave band is plagued by more internally-generated noise than are the shortwave bands.

(Click here to view this video on YouTube.)

Note that YouTube’s copyright checking system flagged my video because it recognized the song being played in the background on WTZQ. I believe this easily qualifies as fair use since the clips are short and it’s an off-air recording with dialog on top. I’ve disputed this, but YouTube may choose to delete this video.  In anticipation, I’ve saved the audio from this video–you can listen to it by clicking here.

In a nutshell, AM performance on the Kaito KA108 is frankly poor. Even when I tuned to strong local stations, the audio sounded muffled and distorted, much as in the Radio Havana Cuba example above.

So you can forget about using the KA108 for mediumwave DXing.

MP3/WAV Playback and recording

There are some redeeming virtues with the KA108, however.  Here’s a positive: digital playback with the KA108 is fantastic. I’ve played a wide variety of audio files on the KA108, and am very impressed with its on-board MP3/WAV player. While audio characteristics unfortunately cannot be adjusted––i.e., there’s no equalization––I find the default audio settings well-balanced for both music and voice.

The KA108 has a dedicated MicroSD slot and a covered USB slot on top of the unit.

The KA108 has a dedicated MicroSD slot and a covered USB slot on top of the unit.

Recording directly from shortwave and mediumwave is also quite good. I believe its on-board recorder is perhaps the best I’ve tried in recent portables; it’s a marked improvement over that of the Kaito KA29, for example. It seems to capture the receiver’s produced audio well, with only a slight, high-pitched “hiss” injected in the audio, though this is not a major distraction.

Sadly the main distraction is that the recorder is recording audio, as I’ve outlined above, from a sub-par receiver.

Still, as an MP3/WAV player, it’s brilliant, and boasts excellent audio.

Summary

Invariably, all radios have strengths and weaknesses; here’s a list of my notes from the moment I put the KA108 on the air:

Pros:

  • Great portable size
  • Clear back-lit display
  • Numerous recording and playback features
  • Audio via MP3 or headphones is strong, considering the small speaker with acoustic chamber provides more bass response and volume than comparable portables (see con)
  • Excellent FM reception
  • Excellent MP3/WAV playback with well-balanced audio fidelity
  • Recorder schedule function
  • Alarms and sleep timers easy to use
  • Dedicated MicroSD and USB slots on top of chassis

Cons:

  • Mediocre sensitivity on SW and MW
  • Internally-generated noise on MW and SW
  • Audio (via built-in speaker) is:
    • too bass-heavy, lacks treble on MW/SW
    • garbled and mushy on MW/SW
    • “hot” and often splatters/distorts when signals are strong
  • Tuning
    • extended mute between frequency changes
    • no “scan to next station” function (only ATS)
  • Odd numeric keypad layout
  • Any local RFI garbles reception even further on SW/MW
  • No SSB (in fairness, few radios in this price class have SSB)
  • Antenna swivel to the front somewhat blocked by the radio’s chassis
  • No backstand

Conclusion

I really wanted the Kaito KA108 to be a strong––or even average––performer. Why? Because, like many of you, I would love to have a capable shortwave/mediumwave radio with built-in digital recording and playback.

Kaito-KA108-AM

Sadly, the KA108 falls short on multiple levels.

Concerned that I might have simply received a defective unit––as I did when I reviewed the Sangean ATS-405––I contacted Kaito Electronics USA. I mentioned my disappointment with the radio’s performance, and detailed the negatives mentioned in this review.

I asked Kaito’s technician if I might have received a defective unit? He responded that my experience seems to be the norm with this particular production run. He, too, had noted muffled/garbled audio on shortwave and mediumwave. Per his request, I sent a detailed list of the KA108’s shortcomings with suggested fixes. He is planning to send this to Kaito’s current manufacturer in China.

The KA108’s poor performance issues would likely be mitigated to a great extent, if the manufacturer would simply make the following adjustments:

  1. Widen the AM bandwidth
  2. Tweak the AGC for greater stability
  3. Adjust the audio settings for the AM mode
  4. Minimize/shorten muting between frequency changes
  5. Improve internal shielding and grounding
  6. And while they’re at it, have the radio manual edited by a native English speaker

Since this is a DSP-based radio, I imagine the first four adjustments can be made via firmware upgrades.

Time will tell if the second production run of the Kaito KA108 improves on the first.  Fingers crossed…!  Kaito, we’d like you to succeed on this score.

Again, many thanks to Universal Radio for supplying me with a KA108 for this review.