Category Archives: Radios

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.

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Help using crystal calibration on the Toshiba RP-2000F

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Many thanks to SWLing Post contributor, Darren Davies, who writes:

Hello Thomas,

I was gifted the Toshiba BCL receiver by an old work colleague. It’s an absolute beauty, in excellent condition and is unusual in that in comes with UK FM band and not the more popular Japanese one. It wipes the floor with newer radios on MW.

I writing to ask if any of your readers have any idea how to use the crystal calibration system. There’s very little information about the radio online and I’d like to get it into tip top condition.

Absolutely love your site and look forward to your daily emails. Keep up the good work.

Cheers Darren

First of all–wow! I love the design of this Toshiba. It’s brilliant that it even has built-in rails to protect the front panel. Obviously a radio that beckons to be taken to the field! Thanks for sharing your photos, Darren.

Post readers: If you know how to calibrate this Toshiba RP-2000F, please comment!

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

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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

In 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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Flea Market Find: David restores a Hammarlund HR-10 solid-state portable

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Many thanks to SWLing Post contributor, David Korchin, who writes:

Stumbled on this rig at an estate sale and laid out a cool $5.00 for her. She was mostly in pieces in a big plastic bag covered in a LOT of dust, and the battery compartment had seen better days. But I thought I could get it going.

Once I got to the chassis I noticed someone with a Golden Screwdriver had been rooting around in there (the PS module was missing screws to the frame and there was some solder bits dancing around inside).

Threw in 4 C cells: pots were noisy, but there was sound, and after liberal application of De-Oxit and some scrubbing the thing snapped to life! Quite good MW reception: I snagged KMOX 1130 St. Louis at 06:30 GMT this morning, a good hop of 960 miles.

Hammarlund only made this Weather/Marine band receiver in 1969-70, so it’s a rare bird, though probably not collectable, per se. Still, it was fun to get the thing operational.

Oh wow! Thanks so much for sharing your flea market find with us, David! I’m so glad you were able to not only give this HR-10 a proper clean-up, but also bring her back to life–and even snag some DX!

And your photos, as always, are simply gorgeous.

I’m curious if anyone else in the SWLing Post community owns or has owned the Hammarlund HR-10. Please comment!

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The HobbyPCB IQ32 transceiver fills a special niche in the ham radio world

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The following review was first published in the September 2020 issue of The Spectrum Monitor magazine:

The HobbyPCB IQ32 transceiver fills a special niche in the ham radio world

This summer, I’ve been exploring the world of general coverage QRP transceivers. I’ve been taking my LnR Precision LD-11, Elecraft KX3 and KX2 into the field; and I’ve just finished a comprehensive review of the Xiegu G90. I also have a TX-500 and IC-705 arriving in the near future [update].

Yes, I’ll admit, I’m a devotee of the “all-in-one” nature of the latest model portable QRP transceivers.

Most of the QRP transceivers now on the market are products of large, popular ham radio manufacturers. Usually, a company will come up with a product concept, follow through with their market research, then design, develop, and produce the radio. In fairness, that’s an over-simplification of the process, but let’s just call it a “top down” design approach––meaning, the product idea is generated within the company, and is often based upon customer feedback.

Not all ham radio products come about this way, though. Some have more “grassroots” or collaborative origin.

The HobbyPCB IQ32

(Image Source: HobbyPCB)

I first noticed the HobbyPCB IQ32 transceiver at the Dayton Hamvention a few years ago. I checked it out carefully at their booth, and recall a crowd gathering around their table. Noting this, I decided, at a later time, I would also find an opportunity to check out the radio in more detail.

A couple of months ago, I was working on my list of General Coverage QRP Transceivers and asked for help filling in details of any radios I’d forgotten. A reader commented and reminded me that the IQ32 was, indeed, general coverage.

At this point, I reached out to HobbyPCB and asked for a loaner unit to explore for a few weeks. The company very kindly sent one my way some weeks ago, and I’ve been testing it on the air ever since.

Form factor

When I received the IQ32 package, I was surprised by how lightweight this transceiver is: a mere 1.5 lbs (700 grams) packs it all in one compact package.

The chassis is made of aluminum and incredibly sturdy. It even includes side panel extensions to protect the front faceplate and knobs.

The IQ32 sports a 3.2″ color LCD touch-screen display large enough to contain all of the functions, a spectrum display, and even an area for text––both transmitted and received in PSK31 and CW. The display is reminiscent of the uBITX V6 I recently reviewed. It is recommended that the operator uses a blunt plastic stylus (or retracted ballpoint pen) for navigating the color screen, since several of the menu settings, memories, and the like require some fairly precise tapping. The graphic user interface (GUI) feels a bit like what I’d expect to find on a piece of test equipment: a bit old school, but nonetheless quite functional.

The main encoder and selector knobs are lightweight and made of some sort of plastic or nylon. They work quite well––but if I owned an IQ32, I believe one of the first things I’d do is replace those with a lightweight aluminum equivalent.

As I mentioned earlier, the weight of the IQ32 is very reasonable at 1.5 lbs. I don’t think I’d even notice it packed in a backpack.

The IQ32, like the recently released Lab599 TCX-500, lacks an internal speaker. However, my unit came with a speaker microphone, which works fine.

The right side panel of the IQ32 has a toggle power switch, power amplifier connection, power port (5mm X 2.1mm, positive tip), PS2 keyboard connector, USB Type A, and a BNC antenna port. The left side has a 3.5mm I/Q Output, 3.5mm headphone jack, 3.5mm speaker/mic port, and a 3.5mm CW key input.

The IQ32 also has two legs that can be adjusted so that the radio will prop up at a comfortable angle for operation. The legs can be a bit finicky to adjust and keep in place, so I preferred using an angled radio support I use for my Elecraft KX3.

A collaboration

The IQ32 also feels like a project joint effort, bringing to mind the old chocolate-peanut butter cup commercial of a bygone era: “My chocolate got mixed with your peanut butter!” And or, “My peanut butter got mixed with your chocolate!”

Curious about this seeming blend of radio ideas, I reached out to Jim Veach (WA2EUJ) at HobbyPCB for more information; he gave me a little history behind the IQ32.

Jim writes:

The IQ32 is the fusion of two products: the HobbyPCB RS-HFIQ, and the STM32-SDR.

The RS-HFIQ was designed to be a 80-10M, 5W soundcard-based SDR––similar to the popular Softrock SDRs with some expansions and revisions.

The STM32-SDR was designed to work with a soundcard-based SDR and [thus] eliminate the need for a PC and provide stand-alone operation.

Inside the IQ32 is a mostly stock RS-HFIQ (in fact, we offered an upgrade kit so RS-HFIQ owners could go the IQ32 route) and a custom version of the STM-32 […] specifically for the IQ32.

The original development of the STM32 [began] a few years ago when PSK31 was the digital mode du jour and [the] PS2 keyboard roamed the land. The firmware team recently released the current FW, which greatly expanded the CW modes and reworked the memory structure based on user input.

And there you have it: even though this unique little rig has been around for a few years, I’m impressed that they continue to refine it and upgrade the firmware. Indeed, if the community of IQ32 users grow, they may be able to do even more.

On the air

To be clear, my intention here isn’t to conduct a comparative review of the IQ32. I simply want to convey what I’ve learned in the process of playing with the rig and trying out some of its unique features.

Immediately after unboxing the radio, I hooked it up to my main skyloop antenna, plugged in the power supply that accompanied the radio, then plugged in the handheld speaker mic.

I discovered rather quickly that the IQ32 user interface takes a different approach than any other transceiver I’ve ever tested. Instead of one main user interface window in which you navigate modes, frequencies, and perhaps alter spectrum and bandwidth settings, the IQ32 has a different screen layout for each mode. It’s as if each mode––SSB, PSK31, CW, etc.––has its own “page.”

Despite the very minimal controls, you can adjust many of the IQ32s settings, macros, and memories in a very granular way via the settings pages using a stylus for fine control of the screen. On the flip side, during operation, it can be frustrating when adjustments need to be made quickly between the AF Gain, RF Gain, CW Speed, and AGC, as they all use the same multi-function knob and switching between them requires several screen taps––not as quick a process as one might prefer.

Indeed, the IQ32 isn’t immediately as intuitive as most commercially-marketed radios. But once you fully understand the settings and modes pages, it becomes easy to navigate. Note: I would advise any future owner of an IQ32 to read the manual in advance. I did this, and it certainly helped. I should add here that the IQ32 manual is one of the most comprehensive I’ve read––especially considering its collaborative roots.

Now, let’s talk modes.

SSB

Since the IQ32 requires a PS2 keyboard for PSK31, and optionally for CW, I tried my hand at SSB first.

After learning how to switch modes and filter settings, I hopped on the air. Instead of calling CQ, I decided instead to seek a park activator in the POTA program via the POTA spots website. Within 10 minutes, I made contact with two parks: one in Pennsylvania and one in Florida on the 40 and 20 meter bands, respectively. While both parks gave me a “5×9” report, I seriously doubt it was accurate based on their own signal strength. (Some park activators, like contesters, only give 5×9 reports.)

Still, my success in contacting these two parks told me that the mic settings were probably suitable and that the audio had enough punch on 5 watts to be heard. To confirm, I called CQ a few times and listened to my own signal at a KiwiSDR site in Maryland. The signal was about 5×5, but the audio was clear, clean, and had excellent fidelity.

Over the past few weeks I’ve worked dozens of stations across North America with the IQ32.

PSK31

One of the very unique features of the IQ32 is its ability to natively encode and decode PSK31. This was the second mode I was eager to try.

To use PSK31 on the IQ32, a PS2 keyboard (or USB keyboard with PS2 adapter) must be connected. I searched my shack in vain for a PS2 keyboard, but fortunately, my friend Vlado (N3CZ) came to the rescue and let me borrow one of his keyboards.

Again, note: IQ32 beginners should certainly plan to read the PSK31 section of the IQ32 manual prior to attempting a PSK31 QSO. For starters, you’ll want to enter in your personal information into the tags settings so that you can use your keyboard function keys to automatically send CQs and to answer calls. The manual will also walk you through any other necessary settings.

Once I had everything set up, I started calling CQ on the 20 meter band; unfortunately I had no luck snagging a station. This had less to do with the radio and much more to do with the mode, which has, alas, fallen out of popularity since the advent of FT8. It’s a shame, really, because although PSK31 is a digital mode, it feels much more like a proper QSO than FT8, in my opinion. While I have a lot of respect for FT8, with PSK31, you can, as we hams say, “rag-chew”––a much more personal interaction.

And rag-chewing is exactly what I did. I contacted a friend, we set a sched for a PSK31 QSO, and it was, indeed, fun. The IQ32 has a screen with enough text space so that it’s easy to follow and to read. In fact, with this radio, I don’t feel like a computer is needed.

With the keyboard attached, PSK31 just works…and works quite well. I really like the way this feature has been implemented in the IQ32.

CW

Truly, the IQ32 actually has a lot to offer the CW operator. The IQ32 supports Iambic keyer modes A and B, with speeds up to 35 wpm. You can also adjust the weight of the dits and dahs. The IQ32 doesn’t support full break-in QSK, however: there is a slight delay after sending before the relay puts the radio back into receive mode. At present, this delay is not manually adjustable but is, rather, based on the selected keyer speed.

I’ve been very pleased using the IQ32 in CW mode with my Begali paddles and Vibroplex single lever paddle.

Of course, a really unique feature of this rig is that it provides the operator with the means to use the PS2 keyboard to send CW, just as you can with the PSK31. At present, there is no CW decoder, but for those who feel their fist isn’t quite up to par, you can surprise the operator on the other end by sending perfectly formed and spaced CW by simply typing it on the keyboard. Herein lies a very unique feature and application for the IQ32.

Indeed, as a frequent Parks On The Air (POTA) field activator, I rely very heavily on memory keyers to call CQ, send a park number, as well as give my thanks and 73s to those who contact me. Using a pre-programmed message means that I then have time to log a station while it sends, and to ensure my code is cleaner when I send park numbers––especially since I don’t exactly excel at sending strings of numbers!

With the IQ32, I find I can program full CW messages to play when I simply press one of the function keys on the keyboard. This gives me much better flexibility and control than, say, the built-in memory keyer on my venerable Elecraft KX2.

With the IQ32, a CW op would actually have the choice of never even touching a key, and just sending all messages with the keyboard. While I could never see myself doing that (as I quite enjoy sending CW with a key), the flexibility of pre-programming an array of CW memory messages and having them conveniently at hand is nonetheless quite appealing.

As a CW operator, I’m quite pleased with the IQ32. My only wish would be for a slightly shorter relay hang time for use in contesting or on Field Day.

The IQ32 Niche

While I wouldn’t necessarily recommend the IQ32 as a first transceiver to a newly-minted ham, I can certainly envision a niche market for this unique rig.

For one, I think the IQ32 could satisfy those operators who desire a very clean and stable transmitter. The IQ32 sports a Class A 5-watt power amplifier with individual low-pass filters for each band that exceed FCC requirements for spectral purity. It also has a Temperature-Compensated Crystal Oscillator (TXCO) for frequency stability––truly, this is not common in a radio of this price class.

For another, the IQ32 could be used as a driver for a transverter when operating on VHF or UHF. Another of its unique and useful features is that the user can set an offset to display the transverter output frequency rather than the IQ32-driven frequency.

And, finally, let’s face it: I know of few other radios that you can take to the field, hook up a keyboard, and natively send and decode PSK-31 transmissions. My KX2 can do this to a degree, but I have to input the text as CW, and the number of characters in the display is quite limited. The IQ32 is robust enough to permit you to carry on PSK-31 rag-chews, if you wish. If this is your thing, you’ll definitely want to play with this rig.

Being able to send CW with a keyboard and pre-programmed messages also means CW operators could make their workflow much more efficient in either the shack or the field.

In conclusion, I’ll admit that the IQ32 isn’t as intuitive as other radios and that the ergonomics leave room for improvement. But it’s still a cool little radio. If, after having read this tour of the IQ32, you feel like you’re in this radio’s niche market, then definitely reach out to HobbyPCB: I’ve found their customer care and support to be absolutely benchmark.

All in all, I’ve had a lot of fun tinkering with this unique general coverage QRP transceiver; I expect others like me will, too. Many thanks to HobbyPCB and the IQ32 crew for letting me take a deep dive into this very special little rig!

Click here to check out the IQ32 at HobbyPCB.

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Gary DeBock experiments with FSL antenna nulling to eliminate a “pest” station

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Many thanks to SWLing Post contributor and Ultralight DX enthusiast, Gary DeBock, for sharing the following guest post:

Nulling a local pest with dual FSL Loops

by Gary DeBock

After many dual FSL antenna experiments I’ve finally determined how to effectively cancel out QRM from a local pest that is off to the side (ideally 90 degrees different, but practical from 50 degrees to 90 degrees different) from a weak DX station, although I’m not quite sure of the theory behind this discovery.

This experiment was an attempt to cancel out QRM from a local pest, 950-KJR in Seattle, WA (35 miles/ 56 km to the north) and chase 950-KKSE in Parker, CO (1005 miles/ 1617 km to the southeast) during the early morning hours. The receiver was a basic (non-SSB) C.Crane Skywave, and two identical 5 inch ferrite rod FSL antennas were used. Please refer to the photo (above) to follow this description.

Step 1) Null out the pest station with the portable radio’s loopstick (away from the FSL antennas). Set the radio down in this nulled position, so that the pest station is as weak as possible, while ensuring that there is space to set up the FSL antennas to the back and side (see photo).

Step 2) Take the “Reception FSL” and use it to peak the pest station’s frequency, setting it up parallel to the portable radio as shown, at the position providing the maximum inductive coupling gain. This will temporarily boost up the pest station, which previously was nulled.

Step 3) Take the “Nulling FSL” and pretune the frequency to that of the pest station. You can do this either by adjusting the variable cap plates to match those of the “Reception FSL,” or by temporarily peaking the pest station’s signal in a position in front of the portable radio. After setting this frequency, set the “Nulling FSL” off to the side of the portable radio as shown, with the spacing identical to the spacing between the radio and the “Reception FSL.”

Step 4) Slowly and carefully tune the “Nulling FSL” until you hear the pest station’s signal take a sharp drop. This setting will be very sharp, but once you find this position you will have nulled out the pest very effectively, and if another station is on the frequency, it may suddenly become dominant, even if it is far away (like 950-KKSE in Denver).

Some MP3’s from this morning’s experiments:

950-KJR in nulled position with the portable only

950-KKSE generally dominant over the local pest KJR when the “Nulling FSL” is peaked

Fascinating, Gary! I don’t understand the dynamics of why this works, but it’s amazing that it does so effectively. I can think of two MW frequencies in particular where I could put a system like this to the test.

Thank you for sharing!

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Radio Waves: Questions About New HF Stations, Towers Damaged after Hurricanes, Evolution of Ham Radio, and The Vintage Radio Repairman

Radio Waves: Stories Making Waves in the World of Radio

Because I keep my ear to the waves, as well as receive many tips from others who do the same, I find myself privy to radio-related stories that might interest SWLing Post readers. To that end: Welcome to the SWLing Post’s Radio Waves, a collection of links to interesting stories making waves in the world of radio. Enjoy!

Many thanks to SWLing Post contributors Ed, Paul, Bennett Kobb, and Kanwar Sandhu for the following tips:

Questions Remain as New HF Stations Wait for Licenses (DMRNA.info)

Here is the story by Bennett Kobb:
As previously reported here at DRMNA.info, the New York company Turms Tech LLC has applied to the FCC for a license for International Broadcast Station WIPE in New Jersey. The license would cover a station already built under a FCC Construction Permit, and would allow it to begin regular operations.

The FCC announced on August 13, 2020 that this license application was accepted for filing, a routine stage at which the FCC examines the application, and might even visit the station, and if everything is in order it will be licensed.

We’re not sure everything is in order. The application for Construction Permit placed the transmitter site at N 40° 57′ 40.38″, W 73° 55′ 23.97″, the broadcast and communications center surrounding the famous Armstrong Tower at Alpine NJ. Its Application for License, however, specifies N 40° 51′ 40″, W 73° 55′ 23″. (Hat tip to Alex P for noting this discrepancy. More about him below.)

While the substitution of 51 for 57 in the coordinates might seem a simple typo, the FCC typically has no sense of humor about coordinate errors. Commission examiners may wonder why a station intended for a historic radio-TV facility ended up among some Manhattan apartments.

The deeper question with WIPE and another, apparently similar station WPBC, is what these stations are really for and what that means for the FCC Rules. WIPE was extremely vague about its program plans, but told the FCC that it will transmit data obtained from third parties using Digital Radio Mondiale. Putting that tidbit together with exposures in a series of public articles in the media and tech blogs, it would seem that audio programming will not be the central mission of this peculiarly named station, whose principal is a financial executive and forestry entrepreneur without any broadcast experience we could find.

We suspect instead that the WIPE data stream will be used not for broadcasting to the public — the only function permitted to International Broadcast Stations under FCC Rules — but instead will be used for private communication with foreign exchanges for high-speed trading.[…]

KSWL-TV tower crashed into buildings near 210 Interstate Hwy (Brad Dye)

Images of tower damage in Lake Charles, LA Bottom photo by KATC-TV of KSWL-TV tower crashed into buildings near 210 Interstate Hwy

After bombarding coastal areas of southern Louisiana with wind gusts up to 130 mph and a storm surge over nine feet as a hurricane, Laura swept north while also spreading over Arkansas Thursday. Laura weakened to a tropical storm early Thursday afternoon, with winds at 70 mph, according to the National Hurricane Center. Laura is predicted to move through the Tennessee Valley and the Mid-Atlantic today into tomorrow.

Power outages from the storms totaled over 900,000 as of Thursday afternoon, according to PowerOutageUS. The site collects data from utilities nationwide. The bulk of the outages were in Louisiana and Texas, according to ABC News. Mississippi reportedly had over 9,400 customers without power as of Thursday morning, reported the Clarion Ledger.

Louisiana and Texas had the most cell site outages as of Thursday mid-day, according to the FCC’s Disaster Information Reporting System. Of the 4,650 cell sites served in Louisiana, 380 were not working. Over 200 of the site outages were due to a lack of power, 141 had a transport issue and 16 were damaged.

Calcasieu and Cameron counties were hit especially hard. 140 sites (75 percent) were not working in Calcasieu County and 20 (69 percent) were out in Cameron County.

Of the 17,621 cell sites served in Texas, 113 were non-operational.

Jefferson County was the hardest hit, with 39 (15.8 percent) out of 247 sites not working. Just over 45 of the non-working sites were out due to a lack of power, 41 for transport reasons and 20 were damaged, according to DIRS.

Cable and wireline companies reported 192,915 subscribers out of service in the affected areas; this may include the loss of telephone, television, and/or Internet services.

Three television stations, five FMs and one AM reported they were off-air.[…]

Ham radio is dying! No it’s not, it’s evolving (K0LWC)

I’ve heard ham radio is dying since as far back as I can remember. It’s one of those common sayings you always hear. Like, “get off my lawn,” and “kids these days.” But is it true? Is there any evidence to support this? Let’s take a closer look.

Data from the ARRL shows that ham radio licensees are increasing. When you look at the chart above, you see two significant markers that are likely driving this growth.

The removal of the code requirement by the FCC.

The economic collapse of 2008.

The Morse code requirement was always an intimidating part of obtaining your General FCC license. Learning Morse code is like learning a second language. It takes time and effort to learn, and that’s not a bad thing. However, it doesn’t change that it scared many people away from the hobby. When the FCC removed this requirement in 2007, I believe it opened the door for many who spent years on the fence. Then you have the economic downturn of 2008. What does that have to do with ham radio? A lot.

After the economic downturn, the United States watched as survivalism, now commonly calling “prepping,” entered mainstream culture. People were worried as the country was involved in multiple wars and our economy was on the brink of collapse. Citizens stocked up on food storage, water, firearms, and…communications equipment. As our country spiraled into more turmoil ham radio licenses steadily increased to more than 750,000 by the end of 2019.[…]