Category Archives: Reviews

The new Belka-DX: Georges’ short review and tests

Many thanks to SWLing Post contributor, Georges Ringotte (F6DFZ), who writes:

I received the Belka-DX a few days ago, and it appears to be an outstanding receiver considering its price, its size, and quality of construction.

AGC and audio reproduction are way better than any Chinese SW receiver giving some superb receptions in CW, SSB and AM.

I shall not repeat that other have said, but I must add that the AM2 pseudo synchronous reception seems good to my ears and a bonus with weak signals.

I made some measures :

  • MDS is about -127 dBm in SSB mode, slightly better in CW mode
  • Sensitivity is constant from 1.5 to 30 MHz
  • Image rejection is over 70 dB, better than a KX3 that I tested a few years ago
  • I couldn’t measure selectivity because my HP generator is somewhat noisy, but the Belka-DX is very good, and also way better than Chinese receivers
  • “S meter” is calibrated as follows: -107 dBm = 10 and -37 dBm = 80, and on this range a 10 change equal a 10 dB change, very accurately. Over -37 dBm, S meter doesn’t move any more.
  • Even on my 2x18m center fed or my Hexbeam, I didn’t notice any signs of overload, but as you know the propagation is not outstanding, and BCL stations are not as bothersome as 40 years ago!
  • there are a few birdies, but if you move your frequency 100 Hz away, they disappear

In my opinion, considering the superb quality of reception, this receiver is outstanding.

Best regards.

Georges

Thank you for sharing this, Georges! Sounds like the Belka-DX is a performer!

CHA MPAS Lite: A proper quick-deployment field antenna

Chameleon Antenna recently sent me a prototype of their latest antenna: the CHA MPAS Lite.

The MPAS Lite is a compact version of their MPAS 2.0 modular antenna system and designed to be even more portable.

Chameleon Antenna is a specialist antenna manufacturer that makes military-grade, field portable antennas that are low-profile and stealthy. Chameleon products are 100% made in the USA and their customers range from amateur radio operators to the armed forces.

Their antennas are not cheap, but they are a prime example when we talk about “you pay for what you get.” In all of my years of evaluating radio products, I’ve never seen better quality field antennas–they’re absolutely top-shelf.

Zeta

I’m currently in my hometown doing a little caregiving for my parents. I’d only planned to be here for a couple of days, but when I saw that the remnants of Hurricane Zeta would pass directly over us with tropical storm force winds and rain, I stuck around to help the folks out.

Zeta struck quite a blow, in fact. No injuries reported, but over 23,000 of us have been without power for over 34+ hours in Catawba county. With saturated grounds, the winds toppled a lot of trees and damaged power lines.

Yesterday, I wanted to take advantage of the power outage and get on the air. I couldn’t really do a POTA activation because I needed to manage things here at my parents’ house. Plus, why not profit from the grid being down and bathe in a noise-free RF space–?

I decided to set it up in their front yard.

CHA MPAS Lite

I had never deployed the MPAS Lite before, so I did a quick scan through the owner’s manual. Although the MPAS Lite (like the MPAS 2.0) can be configured a number of ways, I deployed it as a simple vertical antenna.

Assembly was simple:

  1. Insert the stainless steel spike in the ground,
  2. Attach the counterpoise wire (I unraveled about 25′) to the spike
  3. Screw on the CHA Micro-Hybrid
  4. Screw the 17′ telescoping whip onto the Hybrid-Micro
  5. Extend the whip antenna fully
  6. Connect the supplied coax (with in-line choke) to the Hybrid-Micro
  7. Connect the antenna to the rig

Although I had the Icom IC-705 packed, I wanted to keep things simple by using the Elecraft KX2 I’d also packed since it has a built-in ATU.

Important: the CHA MPAS Lite requires an ATU to get a good match across the bands.

I wasn’t in the mood to ragchew yesterday, but I thought it might be fun to see how easily I could tune the MPAS Lite from 80 meters up.

I checked the Parks On The Air spots page and saw NK8O activating a park in Minnesota in CW:

He was working a bit of a pile-up, but after three calls, he worked me and reported a 559 signal report. Not bad at 5 watts!

I then moved to 40, 18, and 20 meter and called CQ a couple times to see if the Reverse Beacon Network (RBN) could spot me. I like using the RBN to give me a “quick and dirty” signal report. I was very pleased with the bands I tested:

Those dB numbers are quite good for an op running 5 watts into a vertical compromised antenna.

The KX2 very effortlessly got near 1:1 matches on every band I tested.

Of course, after working a few stations in CW and SSB, I tuned to the broadcast bands and enjoyed a little RFI-free SWLing. Noting 13dka’s recent article, I’m thinking on the coast, the MPAS Lite will make for a superb amateur radio and SWLing antenna.

Durability

Although the remnants of Zeta had effectively passed through the area three hours prior, it was still very blustery outside. I was concerned gusts might even be a little too strong for the 17′ whip, but I was wrong. The whip handled the wind gusts with ease and the spike held it in place with no problem.

One of the things I have to watch with my Wolf River Coils TIA vertical is the fact it’s prone to fall in windy conditions and many ops have noted that this can permanently damage the telescoping whip (the weak point in that system).

I’m pretty certain this wouldn’t happen with the Chameleon 17′ whip–it feels very substantial and solid.

Ready to hit the field with the CHA MPAS Lite!

I’m a huge fan of wire antennas because I believe they give me the most “bang-for-buck” in the field, but they’re not always practical to deploy. I like having a good self-supporting antenna option in my tool belt when there are no trees around or when parks don’t allow me to hang antennas in their trees.

I’ve got a park in mind that will make for a good test of the CHA MPAS Lite: it’s a remote game land with no real parking option. I’ll have to activate it on the roadside–an ideal application for the MPAS Lite.

Click here to check out the CHA MPAS Lite.

Matt’s mediumwave audio comparison of the C.Crane Radio 2E and the Potomac Instruments FIM-41

Many thanks to SWLing Post contributor, Matt Blaze, who writes:

I did another head-to-head receiver comparison, this time of two MW BCB AM portables: The C.Crane Radio 2/e vs. the Potomac Instruments FIM-41 field intensity meter.

The latter is not intended as a receiver, but rather a test instrument, but it turns out to be the among most sensitive MW receivers I’ve ever used. So I thought it would be interesting to compare its performance with that of a well-regarded modern portable.

Audio Comparison:

Our two contenders with comparable portable radios: the GE Super Radio, Panasonic RF-2200, and Sony ICF-EX5MK2.

Another brilliant audio comparison, Matt! Thank you so much for taking the time to put this together! I actually believe audio comparisons, as you’ve set them up, are a fantastic way of sharing A/B comparisons.

Click here to check out all of Matt’s receiver audio comparisons.

Icom IC-705 blind audio tests: Let’s take a look at your choices!

Before I had even taken delivery of the new Icom IC-705 transceiver, a number of SWLing Post readers asked me to do a series of blind audio comparison tests like I’ve done in the past (click here for an example).

Last week, I published a series of five audio tests/surveys and asked for your vote and comments. The survey response far exceeded anything I would have anticipated.

We received a total of 931 survey entries/votes which only highlights how much you enjoy this sort of receiver test.

In this challenge, I didn’t even give you the luxury of knowing the other radios I used in each comparison, so let’s take a look…

The competition

Since the Icom IC-705 is essentially a tabletop SDR, I compared it with a couple dedicated PC-connected SDRs.

WinRadio Excalibur SDR

The WinRadio Excalibur

I consider the WinRadio Excalibur to be a benchmark sub $1000 HF, mediumwave, and longwave SDR.

It is still my staple receiver for making off-air audio and spectrum recordings, and is always hooked up to an antenna and ready to record.

In the tests where I employed the WinRadio Excalibur, I used its proprietary SDR application to directly make recordings. I used none of its advanced filters, AGC control, or synchronous detection.

Click here to read my original 2012 review of the WinRadio Excalibur.

Airspy HF+ SDR

The Airspy HF+ SDR

I also consider the Airspy HF+ SDR to be one of the finest sub-$200 HF SDRs on the market.

The HF+ is a choice SDR for DXing. Mine has not been modified in any way to increase its performance or sensitivity.

In the test where I employed the HF+ I used Airspy’s own SDR application, SDR#, to directly make recordings. I used none of its advanced filters, AGC control, noise reduction, or synchronous detection.

Belka-DSP portable receiver

The Belka-DSP

I recently acquired a Belka-DSP portable after reading 13dka’s superb review.

I thought it might be fun to include it in a comparison although, in truth, it’s hardly fair to compare a $160 receiver with a $1300 SDR transceiver.

The Belka, to me, is like a Lowe HF-150 in a tiny, pocket package.

Elecraft KX3 QRP transceiver

The Elecraft KX3

The KX3 is one of the best transceivers I’ve ever owned. Mine has the CW roofing filter installed (only recently) and is, without a doubt, a benchmark performer.

Click here to read my full review.

If you check out Rob Sherwood’s receiver test data table which is sorted by third-order dynamic range narrow spaced, you’ll see that the KX3 is one of the top performers on the list even when compared with radios many times its price. Due to my recording limitations (see below) the KX3 was the only other transceiver used in this comparison.

Herein lies a HUGE caveat:

The WinRadio application

As I’ve stated in SDR reviews in the past, it is incredibly difficult comparing anything with PC-connected SDRs because they can be configured on such a granular level.

When making a blind audio test with a stand-alone SDR radio like the IC-705–which has less configurability–you’re forced to take one of at least two paths:

  • Tweak the PC-connected SDR until you believe you’ve found the best possible reception audio scenario and use that configuration as a point of comparison, or
  • Attempt to keep the configuration as basic as possible, setting filters widths, AGC to be comparable and turning off all other optional enhancements (like synchronous detection, noise reduction, and advanced audio filtering to name a few).

I chose the latter path in this comparison which essentially undermines our PC-connected SDRs. Although flawed, I chose this approach to keep the comparison as simple as possible.

While the IC-705 has way more filter and audio adjustments than legacy transceivers, it only has a tiny fraction of those available to PC-connected SDRs. Indeed, the HF+ SDR, for example, can actually be used by multiple SDR applications, all with their own DSP and feature sets.

In short: don’t be fooled into thinking this is an apples-to-apples comparison. It is, at best, a decent attempt at giving future IC-705 owners a chance to hear how it compares in real-word live signals.

Recordings

The Zoom H2N connected to my Elecraft KX2.

Another limiting factor is that I only have one stand-alone digital audio recorder: the Zoom H2N. [Although inspired by Matt’s multi-track comparison reviews, I plan to upgrade my gear soon.]

The IC-705 has built-in digital audio recording and this is what I used in each test.

The WinRadio Excalibur and Airspy HF+ also have native audio recording via their PC-based applications.

With only one stand-alone recorder, I wasn’t able to simultaneously compare the IC-705 with more than one other stand-alone receiver/transceiver at a time.

As I mentioned in each test, the audio levels were not consistent and required the listener to adjust their volume control. Since the IC-705, Excalibur, and HF+ all have native recording features, the audio levels were set by their software. I didn’t post-process them.

Blind Audio Survey Results

With all of those caveats and disclaimers out of the way, let’s take a look at the survey results.

Blind audio test #1: 40 meters SSB

In this first test we listened to the IC-705, WinRadio Excalibur, and Belka-DSP tuned to a weak 40 meter station in lower sideband (LSB) mode. Specifically, this was ham radio operator W3JPH activating Shikellamy State Park in Pennsylvania for the Parks On The Air program. I chose this test because it included a weak station calling CQ and both weak and strong stations replying. There are also adjacent signals which (in some recordings) bleed over into the audio.

Radio A: The Belka-DSP

Radio B: The WinRadio Excalibur

Radio C: The Icom IC-705

Survey Results

The Icom IC-705 was the clear choice here.

Based on your comments, those who chose the IC-705 felt that the weak signal audio was more intelligible and that signals “popped out” a bit more. Many noted, however, that the audio sounded “tinny.”

A number of you felt it was a toss-up between The IC-705 and the Belka-DSP. And those who chose the WinRadio Excalibur were adamant that is was the best choice.

The WinRadio audio was popping in the recording, but it was how the application recorded it natively, so I didn’t attempt to change it.

Test #2: 40 meters CW

Icom IC-705In this second test we listened to the Icom IC-705 and the Elecraft KX3 tuned to a 40 meter CW station.

Radio A: Icom IC-705

Radio B: Elecraft KX3

Survey Results

The Elecraft KX3 was preferred by more than half of you.

Based on your comments, those who chose the KX3 felt the audio was clearer and signals had more “punch.” They felt the audio was easier on the ears as well, thus ideal for long contests.

Those who chose the IC-705, though, preferred the narrower sounding audio and felt the KX3 was too bass heavy.

Test #3: Shannon Volmet SSB

In this third test we listened to the Icom IC-705 and WinRadio Excalibur, tuned to Shannon Volmet on 8,957 kHz.

Radio A: WinRadio Excalibur

Radio B: Icom IC-705

Survey

The Icom-705 audio was preferred by a healthy margin. I believe, again, this was influenced by the audio pops heard in the WinRadio recording (based on your comments).

The IC-705 audio was very pleasant and smooth according to respondents and they felt the signal-to-noise ratio was better.

However, a number of comments noted that the female voice in the recording was actually stronger on the WinRadio Excalibur and more intelligible during moments of fading.

Test #4: Voice of Greece 9,420 kHz

In this fourth test we listen to the Icom IC-705, and the WinRadio Excalibur again, tuned to the Voice of Greece on 9,420 kHz.

Radio A: Icom IC-705

Radio B: WinRadio Excalibur

Survey

While the preference was for the IC-705’s audio (Radio A), this test was very interesting because those who chose the Excalibur had quite a strong preference for it, saying that it would be the best for DXing and had a more stable AGC response. In the end, 62.6% of 131 people felt the IC-705’s audio had slightly less background noise.

Test #5: Radio Exterior de España 9,690 kHz

In this fifth test we listened to the Icom IC-705, and AirSpy HF+, tuned to Radio Exterior de España on 9,690 kHz. I picked REE, in this case, because it is a blowtorch station and I could take advantage of the IC-705’s maximum AM filter width of 10 kHz.

Radio A: Icom IC-705

Radio B: Airspy HF+

Survey

The IC-705 was preferred by 79% of you in this test.

Again, very interesting comments, though. Those who preferred the IC-705 felt the audio simply sounded better and had “punch.” Those who preferred B felt it was more sensitive and could hear more nuances in the broadcaster voices.

So what’s the point of these blind audio tests?

Notice I never called any radio a “winner.”

The test here is flawed in that audio levels and EQ aren’t the same, the settings aren’t identical, and even the filters have slightly different shapes and characteristics.

In other words, these aren’t lab conditions.

I felt the most accurate comparison, in terms of performance, was the 40M CW test with the KX3 because both employed similar narrow filters and both, being QRP transceivers, are truly designed to perform well here.

I essentially crippled the WinRadio Excalibur and Airspy HF+ by turning off all all but the most basic filter and AGC settings. If I tweaked both of those SDRs for optimal performance and signal intelligibility, I’m positive they would have been the preferred choices (indeed, I might just do another blind audio test to prove my point here).

With that said, I think we can agree that the IC-705 has brilliant audio characteristics.

I’ve noticed this in the field as well. I’m incredibly pleased with the IC-705’s performance and versatility. I’ll be very interested to see how it soon rates among the other transceivers in Rob Sherwood’s test data.

The IC-705 can actually be tailored much further by adjusting filter shapes/skirts, employing twin passband tuning and even using its noise reduction feature.

If anything, my hope is that these blind audio tests give those who are considering the Icom IC-705 a good idea of how its audio and receiver performs in real-word listening conditions.


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Matt compares the Tecsun PL-990 and Sangean ATS-909X sharing an external antenna

Many thanks to SWLing Post contributor, Matt Blaze, who shares the following comparison of the new Tecsun PL-990x and the original Sangean ATS-909X communications receivers.

Like Matt’s recent comparison of the Tecsun PL-990x to the Icom IC-R9500, this review is in audio form and brilliantly narrated by Matt. I highly recommend listening with headphones or, at least, an audio device with separate left/right channels as his comparison takes advantage of this.

Enjoy:

Yet another superb presentation, Matt! Thank you so much for taking the time to make these audio comparison tests.

Matt compares the Tecsun PL-990 to the Icom IC-R9500 on an external antenna and the results are surprising

Many thanks to SWLing Post contributor, Matt Blaze, who shares the following comparison of the new Tecsun PL-990x and the benchmark Icom IC-R9500 communications receiver.

Matt’s excellent comparison  is in audio form. I highly recommend listening with headphones or, at least, an audio device with separate left/right channels as his comparison takes advantage of this.

I love not only how he set up this comparison with both radios sharing an identical antenna, but his evaluation also explores how well the PL-990 handles a proper external antenna via its external antenna jack.

Click below to listen to Matt’s piece, or right click here to download the audio:

Thanks for sharing this, Matt. You’ve inspired me to do similar narrated audio comparisons!

Shortwave listening in the field with the Icom IC-705 transceiver

Yesterday, I took the new Icom IC-705 to the field for another Parks On the Air (POTA) activation. My goal at this particular activation was to make a couple of posts for QRPer.com: first, to test the new mAT-705 ATU on loan from Vibroplex, and secondly, make a short video about full break-in CW operation.

I also wanted to do a little shortwave listening after completing the activation. I had no idea what propagation would be like, but thought I’d tune around below the 20 meter band where the antenna was currently resonant.

I deployed the CHA Emcomm III Portable random wire antenna which, I must say, is a superb shortwave listening antenna for the field.

Since you can’t see the antenna in the first photo below, I marked up the second one. The blue line represents the 73′ radiator, and the green line the counterpoise:
Here’s the short video I made around the 22 meter band:

I had planned to make a few audio recordings via the built-in digital recorder but I left my MicroSD card at home. No worries, though, as I plan to make some recordings for readers to compare in the coming days if time allows.

If you have any questions about the IC-705, feel free to ask in comments.