Category Archives: Ham Radio

Radio Waves: Hammarlund Legacy, FM Radio Using Arduino, VOA Report on Bias, ARISS SSTV Event, and Geminids

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 Trevor, Dan Robinson, and the Southgate ARC for the following tips:

Ham radio operators honor legacy of Mars Hill company (Citizen Times)

During the 1950’s and ’60’s, when the Hammarlund Manufacturing Company had a factory just west of Mars Hill College, the town could have been considered a world center of advanced electronic technology. With a company motto of “Quality Without Compromise,” almost 90% of American WWII wartime military electronic equipment employed Hammarlund capacitors. They also built U.S. Navy search radar installed on aircraft carriers, battleships and cruisers.

Hammarlund was one of the three leading brands of radio communications equipment at the time, along with Hallicrafters and Collins Radio. These three companies dominated in providing state of the art electronics equipment to the U.S. military, large and small corporations, and to private individuals who had the means and taste to own the very best.

Hammarlund Radio initially operated out of New York City starting in 1910, in the early days of radio. They began consolidating all of their operations in Mars Hill in 1951, in a newly constructed facility that spread out to over 100,000 square foot on Hammarlund Drive — now named Hickory Drive. The site employed hundreds from around the area and their work lives on today. […]

FM Radio From Scratch Using An Arduino (Hackaday)

Building radio receivers from scratch is still a popular project since it can be done largely with off-the-shelf discrete components and a wire long enough for the bands that the radio will receive. That’s good enough for AM radio, anyway, but you’ll need to try this DIY FM receiver if you want to listen to something more culturally relevant.

Receiving frequency-modulated radio waves is typically more difficult than their amplitude-modulated cousins because the circuitry necessary to demodulate an FM signal needs a frequency-to-voltage conversion that isn’t necessary with AM. For this build, [hesam.moshiri] uses a TEA5767 FM chip because of its ability to communicate over I2C. He also integrated a 3W amplifier into this build, and everything is controlled by an Arduino including a small LCD screen which displays the current tuned frequency. With the addition of a small 5V power supply, it’s a tidy and compact build as well.[…]

2016 Report Confirmed Problem of Political Bias At Voice of America (USAGM Watch)

by Dan Robinson

Trump USAGM CEO Michael Pack Was Attacked For Attempts to Focus on Problem

It was May of 2016 and Amanda Bennett was only a few weeks into what would become a nearly four year stint as director of the Voice of America, among the “plum” jobs in Washington, D.C.

Bennett was just getting her feet wet, and at the time was dependent on a group of longtime embedded VOA managers that she would at one point describe as a “fantastic leadership team.”

She had received fair warning, from former VOA employees and extensive reporting by the independent watchdog website BBG and USAGM Watch, of disturbing issues at VOA, located in what has long been one of the most dysfunctional of federal agencies.

Some VOA journalists were using their taxpayer-funded positions to engage in self-promotion and campaign for political causes, a fact little known to most Americans. VOA’s website and digital operations were plagued by failures in breaking news coverage, and inaccuracies in content.

Both VOA and what was then called the Broadcasting Board of Governors (BBG) were increasingly seen by U.S. lawmakers as moribund. A Republican-led and eventually bipartisan effort in Congress proposed major restructuring – there was little patience left on Capitol Hill where the agency was increasingly considered to be “broken,” “rudderless,” and “worthless.” President Obama signed the reform legislation in December 2016 to create a powerful agency CEO position and to make the BBG Board purely advisory.[…]

ARISS Slow Scan TV event (Southgate ARC)

An ARISS Slow Scan TV (SSTV) event is scheduled from the International Space Station (ISS) for late December. This will be a special SSTV event to celebrate the 20th anniversary of ARISS.

The event is scheduled to begin on December 24 and continue through December 31.

Dates are subject to change due to ISS operational adjustments.

Dave, AA4KN
ARISS PR

The Geminids – a reminder (Southgate ARC)

The Geminids are a prolific meteor shower caused by the object 3200 Phaethon, which is thought to be a Palladian asteroid with a “rock comet” orbit. This would make the Geminids, together with the Quadrantids, the only major meteor showers not originating from a comet.

They are the biggest meteor shower of the year, and normally occur between 4 December – 17 December.

The peak is expected on 14 December.

Expect FM “pings” and hopefully interesting dx opportunities.

Mike

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Solar Cycle 25: Sunspot Cycle “Could Be One Of The Strongest On Record”

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(Source: SpaceRef via Eric McFadden)

In direct contradiction to the official forecast, a team of scientists led by the National Center for Atmospheric Research (NCAR) is predicting that the Sunspot Cycle that started this fall could be one of the strongest since record-keeping began.

In a new article published in Solar Physics, the research team predicts that Sunspot Cycle 25 will peak with a maximum sunspot number somewhere between approximately 210 and 260, which would put the new cycle in the company of the top few ever observed.

The cycle that just ended, Sunspot Cycle 24, peaked with a sunspot number of 116, and the consensus forecast from a panel of experts convened by the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA) is predicting that Sunspot Cycle 25 will be similarly weak. The panel predicts a peak sunspot number of 115.

If the new NCAR-led forecast is borne out, it would lend support to the research team’s unorthodox theory – detailed in a series of papers published over the last decade – that the Sun has overlapping 22-year magnetic cycles that interact to produce the well-known, approximately 11-year sunspot cycle as a byproduct. The 22-year cycles repeat like clockwork and could be a key to finally making accurate predictions of the timing and nature of sunspot cycles, as well as many of the effects they produce, according to the study’s authors.[…]

Click here to continue reading the full article.

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A comprehensive review of the Mission RGO One general coverage 50 watt transceiver

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

A review of the Mission RGO One ham radio transceiver

by Thomas (K4SWL / M0CYI)

Wow…I love this!

If I am perfectly frank, that would sum up my initial impression of the Mission RGO One.

It was the 2018 Hamvention in Dayton, Ohio, and I had just met up with radio engineer Boris Sapundzhiev (LZ2JR) who was debuting the prototype of his 50-watt transceiver kit, the Mission RGO One. With its clean, functional design and simple front face, large weighted encoder, and enough tactile buttons and multi-function knobs to keep one’s most needed features within reach, the kit was certainly pushing all the right buttons for me. Without a doubt, I was impressed from the start.

Boris (LZ2JR) the designer and engineer of the Mission RGO One.

To my mind, the RGO One smacks of classic 1990s-era transceivers: a traditional tabletop front-facing panel, a large fold-out bail, and a unfussy backlit LCD display that’s large enough to read in the field and viewable at any angle.

Perhaps it’s only because I can’t turn off the innate radio reviewer, that I was rapidly checking mental boxes in this first encounter with the RGO One. Indeed, when I first set eyes on any new radio, I do skim through my mental “operations checklist” to see how difficult the rig might be to use at home and/or in the field. Specifically, I’m looking for the following controls:

Encoder
AF Gain
RF Gain
Mode switch
Power output adjustment
Tune/Xmit button
Preamp/Attenuator
VFO A/B
Split and A=B
Mic gain and keyer speed
RIT
Filters
Band switching and direct frequency entry
Key and encoder lock

Of course, these days it’s fairly rare that radios actually contain all of these functions without the user having to dig into layers of menus, multi-function controls, or touch-screen options to access them.

Remarkably enough, the Mission RGO One, despite simple design, manages to include all of these features on the front panel without the need of embedded menus. In contrast with some of the radios I’ve tested and evaluated over the past several years, I could tell by the layout alone that the Mission RGO One was developed by an active ham radio operator and DXer: the controls are that intuitive.

Alas, the tantalizing prototype on Boris’ table in the 2018 Hamvention flea market was for show only.

Boris promised that he’d have fully-functional models available at the 2019 Hamvention. Because of this, following that first meeting in 2018, I kept in touch with Boris; we arranged to meet again at the 2019 Hamvention so I could take a second, much closer look at the RGO One––especially since he intended to start shipping the first very limited, early-production-run rigs shortly afterward.

So…did Boris deliver? And more importantly: did the RGO deliver––? Let’s find out.

On The Air

Within hours of taking delivery of the prototype radio, I had it in the field activating parks.

It was May 2019 when Boris delivered on his promise, handing me a loaner prototype RGO One. He did so with the understanding that the prototype was still a little rough around the edges. I acknowledged this, thinking in terms of a late Beta-test model since he welcomed reports of any bugs or anomalies I encountered and was fully prepared to address them.

After taking the initial RGO One to the field, I did note a few bugs, but nothing major. All of my field notes were then sent to Boris and turned into action items.

Then, in July of 2020, Boris sent me a fully-upgraded Mission RGO One with the new internal ATU and optional adjustable filter. This radio represented the “fully-grown” production model, and in preparation to put it through its paces, I returned the prototype.

Although there are planned hardware upgrade options and, of course, firmware upgrades, the RGO One has now reached full maturity as a transceiver.

However, it was one thing to have ham-friendly ergonomic controls. The real question was, how did the RGO One stack up against the competition? It was time to find out. After all, this is the danger of a “love at first sight” radio encounter––it often leaves the door open for disappointment, and of this I was well aware.

What follows is my full review of this 2020 Mission RGO One transceiver. Let’s take a deep dive into this rig…

Features and specifications

What follows are some of the RGO One features and highlights as written in the product manual (PDF):

QRP/QRO output 5 – 50W [can actually be lowered to 0 watts out in 1 watt increments]
All-mode shortwave operation – coverage of all HAM HF bands (160m/60m optional)
High dynamic range receiver design, including high IP3 monolithic linear amplifiers in the front end, and diode ring RX mixer or H-mode first mixer (option)
Low-phase noise first LO – SI570 XO/VCXO chip
Full/semi (delay) QSK on CW; PTT/VOX operation on SSB. Strict RX/TX sequencing scheme with no “click” sounds
Down conversion superhet topology with popular 9MHz IF
Custom-made crystal filters for SSB and CW and variable crystal 4 pole filter – Johnson type 200…2000Hz
Fast-acting AGC (fast and slow) with 134kHz dedicated IF
Compact and lightweight body, only 5 lbs
Custom-made multicolor backlit FSTN LCD
Custom-molded front panel with ergonomic controls
Silent operation with no clicking relays inside – solid state GaAs PHEMT SPDT switches on RX (BPF and TX to RX switching) and ultrafast rectifying diodes (LPF)
Modular construction – Main board serves as a “chassis” also fits all the external connectors, daughter boards, plus inter-connections, and acts as a cable harness
Optional modules – Noise Blanker (NB), Audio Filter (AF), ATU, XVRTER, PC control via CAT protocol; USB UART – FTDI chipset
Double CPU circuitry control for front panel and main board – both field programmable via USB interface
Memory morse code keyer (Curtis A, CMOS B); 4 Memory locations 128 bytes each

Build quality

First impressions proved accurate in terms of construction. I’m very pleased with the build quality of the Mission RGO One. Keep in mind, however, you might note from the photos that some items––like the volume and multifunction knobs––are 3D printed, and I’m not certain if they’ll ever have custom knobs manufactured. But I really don’t even think this is necessary, as the 3D printed ones are very nice, indeed––moreover, should a replacement ever be needed, I love the idea I could simply print one myself!

The RGO One main optical encoder/tuning knob is just brilliant. It’s weighted properly for the right amount of “heft” while tuning. I’m very pleased with the overall feeling and quality. It’s substantial, yet silky-smooth in operation, just what I look for in a tuning knob.

On the back of the unit, there is an externally-mounted heat sink with two small fans. These fans are quiet and efficient.

The chassis and bail are both top-shelf quality and should withstand years of field use. Just do keep in mind that like almost every other amateur transceiver currently on the market (save the recently reviewed lab599 Discovery TX-500), the chassis is neither water-proof nor weather-proof, so will require common-sense care to protect it from the elements.

Portability

The Mission RGO is relatively compact, lightweight (only 5 lbs without the ATU), and has a power output of up to 55 watts, even though the specs list just 50 watts. As a point of comparison, most other rigs in this class have a maximum output of 10 to 20 watts, and require an external amplifier for anything higher. The form factor is very similar to the Elecraft K2.

The light weight of the rig and the extra power makes the RGO One a capable and versatile field radio. Although the RGO One is configured like a desktop radio (with a front-facing panel), it’s still relatively compact and can easily be set up on a portable table, chair, or on the ground. Unlike field-portable rigs with top-mounted controls (think the Elecraft KX3 or KX2), obviously, it would be tough to do handheld or laptop operation.

The RGO One should also play for a long time on battery power as the receive current drain is a respectable 0.65A with the receiver preamp on. It’s not as efficient as, say, an Elecraft KX3 or the new Icom IC-705, but keep in mind the RGO One can provide 50 watts of output power and has a proper, internally-mounted, amplified speaker. The popular 100 watt Yaesu FT-891, in comparison, has a current drain closer to 1.75 to 2.0 amps [update: actually the specifications indicate 2 Amps in receive, but user reports are less than half that amount]. I pair the RGO One with my larger 15 aH Bioenno LiFePo battery. When fully-charged, I can operate actively for hours upon hours without needing to recharge.

The Bioenno 15aH battery powers the Mission RGO One for hours at a time in the field.

If it’s any indication of how much I wanted to take this rig to the field, when Boris handed me the prototype RGO One on Saturday at the 2019 Hamvention, I had it on the air that same day doing a Parks On The Air activation at an Ohio State Park.

Since then, I’ve easily taken the Mission RGO One on 30 or more park activations.

Performance

What’s most striking and obvious about the Mission RGO One’s receiver from the moment you turn it on is the low noise floor. It’s incredibly quiet. So much so that more than once, I’ve double checked to make sure RF gain hadn’t been accidentally altered as I started a field activation. I’d call CQ a few times, though, and when stations return they literally pop out of the ether. The RGO One currently has no digital noise reduction (DNR) but frankly, I don’t miss it like I might in other transceivers. Indeed, the RGO One is a radio I’ve reached for when the bands are noisy because the AGC and receiver seem to handle rough atmospheric conditions very well.

The RGO One’s built-in, top-mounted speaker provides ample audio levels for the shack, but in a noisy field environment, I wish it had a little more amplification. I’ve also used my Heil Pro headset and even inexpensive in-ear earphones connected to the front panel headphones jack in the field. The audio via headphones is excellent.

Let’s take a look at how well the RGO One performs by mode:

CW

First and foremost, CW operators will appreciate the RGO One’s silky-smooth full break-in QSK. The RGO One employs clickless and quiet pin diode switching–a design feature I’ve become particularly fond of as traditional T/R relays can be noisy and distracting when not using headphones.

The RGO One also has a full compliment of adjustments for the CW operator including adjustable delay (default is 100ms), iambic mode, weight ratio, hand key/paddle, adjustable pitch, and sidetone volume.

The key jack is a standard three conductor 1/8” jack found on most modern transceivers. It’s located on the back of the radio.

My review unit has the optional variable width narrow filter which I highly recommend if operating in crowded conditions. I’ve used the RGO One on ARRL Field Day and found that it easily coped with crowded band conditions. Even after a few hours on the air, I had very little listener fatigue.

I also find that, as I mentioned earlier, CW signals just seem to “pop” out of the ether due to the low noise floor and excellent sensitivity/selectivity.

The RGO one also sports four CW keying memories where you can record your CQ, callsign, or even contest exchange. I’ve become incredibly reliant on memory keying to help facilitate my workflow in the field—while the radio is automatically sending my CQ or my regards and callsign to an station I’ve just worked, my hands are free to log the contact, adjust the radio, or even eat lunch!

Memory keying does require one long-press of the “6” button followed by either the “1,” “2,” “3,” or “4” button to play a message. Occasionally I won’t hold the 6 button long enough and accidentally move my frequency down one meter band since the 6 button is also the band “down” button. While it doesn’t happen often, it’s frustrating when it does but I think it could easily be fixed in the firmware as it’s really a timing issue.

SSB

Likewise, phone operators will be very pleased with the Mission RGO One. During all of my testing, I’ve only used the microphone supplied with the radio mainly because I don’t currently own another radio with an RJ-45 type microphone connector.

I do love the fact the microphone port is on the front panel of the radio—it’s very easy to connect and disconnect (in contract to the recently released Icom IC-705, for example). I’ve gotten excellent audio reports with the RGO One in SSB mode and have even monitored my own tests and QSOs via the KiwiSDR network.

Compression, gain, and VOX controls are easily accessible. One missing feature at present is a voice memory keyer. For field operators activating sites for the POTA, WWFF, or SOTA program, voice memory keying is huge as it saves your voice from calling “CQ” over the course of a few hours. I understand Boris does plan to implement voice memory keying in a future speech processor board.

AM Mode

Since the RGO One has general coverage receive and since I’m a shortwave broadcast listener, I was disappointed to find that there is presently no AM mode. Boris told me he does plan to add AM mode, “to be implemented in future versions of the IF/AF board only on RX.”

With that said, I can always zero-beat a broadcaster and use a wide SSB filter to listen to broadcasts which is more than I could do, for example, with my (ham band only) Elecraft K2.

At the end of the day, the RGO One is a high-performance, purpose-built ham radio transceiver, so the current lack of AM mode isn’t a deal-breaker for me, but I would love a wide AM filter on this rig.

ATU

The 2020 review model I received has the internal automatic antenna tuner which I feel is a worthy upgrade/addition. In the field, I’ve paired the RGO One with my Chameleon CHA Emcomm III Portable random wire antenna which requires an ATU in order to find matches across the bands. The pairing has been a very successful one because the Emcomm III can handle up to 50 watts power output in CW and covers the entire HF band when emptying the RGO One ATU.

Even though it’s a minor thing, I also like the fact that the RGO One ATU operates so quietly, even though with the present firmware it takes longer than some of my other ATUs to find a match.

Power

One thing I’ve found very useful in the field and, no doubt others will as well is the power output. In many ways, the RGO feels like a larger QRP radio (think Ten-Tec Argonaut V or VI) but it’s actually able to pump out 55 watts (often five watts more than specified). In single sideband mode, this is a meaningful amount of power output compared to, say, 5 or 10 watts. When I activate a rare park, or an ATNO (All Time New One), I’ve been taking the RGO One more times than not in order to get the best signal possible and maximum amount of contacts. Running full power, the rig never feels warm—heat dissipation is superb—and the fans on the back of the heat sink are super quiet.

I actually feel like the 50 watts of output power gives the RGO One a market niche since it sports top-shelf performance as you might expect in the venerable Elecraft K2, for example, but not being a 10 watt or 100 watt radio, rather something in between which saves a little weight and also the need for heftier heat dissipation.

Other unique features

The RGO One has some interesting features not found in similar radios.

For one, there are no less than ten color options for the custom backlit LCD display, along with adjustable contrast and backlighting intensity.

The RGO One team also documents how to access hidden admin menus for granular adjustments to transceiver parameters, but of course you’d want to adjust those with caution and note values prior to changing them. When you receive your RGO One, Boris includes a sheet with all default values to make stepping back much easier.

Hands-on philosophy

At the end of the day, the Mission RGO One is a kit that can eventually be purchased in kit form, or as a fully assembled transceiver. It’s modular: you can add and upgrade features as you wish. Some field operators, for example, may wish to omit the ATU to save a little extra weight or cost. I actually love this philosophy and I think it’s one that’s made Elecraft such a successful manufacturer.

The process of upgrading firmware is slightly more involved than you might find with, say, an Elecraft, Icom, or Yaesu product. It’s a two stage process where one upgrades both the front panel and the main board separately. I completed a firmware update only a few weeks prior to publication. It took me perhaps 15 minutes with my PC as I followed Boris’ step-by-step instructions (http://lz2jr.com/blog/index.php/rgo-one-firmware-update-procedure/).

There is also an active email discussion group for the Mission RGO One (https://groups.io/g/RGO-ONE/) where participants share experiences, modifications, and even any glitches or bugs that are discovered. This group is closely monitored by the RGO One team, so items are addressed very quickly. I highly recommend joining this discussion group if you see an RGO One in your future.

Also, I’ve gotten great customer support from Boris (LZ2JR) and have heard the same from group members. He’s very much open to critical customer feedback.

Summary

Every radio has its pros and cons. When I begin a review of a radio, I take notes from the very beginning so that I don’t forget some of my initial impressions. Here is the list I formed over the time I’ve spent evaluating the 2020 production model Mission RGO One.

Pros:

Excellent sensitivity and selectivity
Very low noise floor
Excellent, clean audio (see con)
Silky-smooth QSK
Full compliment of CW and SSB features and adjustments
CW memory keyer
Superb ergonomics with no need to access embedded menus for common features
50 watts output power with effective quiet heat dissipation
Lighter weight compared with comparable transceivers
Direct frequency entry
Standard Anderson Powerpole power port on rear panel

Cons:

No voice keyer memory (at time of posting, but is planned in upgrade)
No notch or auto notch filter (at time of posting, but is planned)
No 6 meter option
No AM mode (at time of posting, but is planned)
Firmware updates are a two stage process
Would like slightly more audio amplification while using internal speaker in noisy outdoor environments

Conclusion

If you can’t tell, I’m impressed with the Mission RGO One because it does exactly what it sets out to do. The RGO One is designed for an operator who appreciates rock-solid performance with simple, intuitive ergonomics.

While teaching an amateur radio course to our homeschool cooperative high school students last year, I picked the RGO One as the best field radio for HF demonstrations.

I’ll never forget setting the (prototype) RGO One for the first time on a folding table outside the classroom under a large tree. I had the students erect both an end-fed resonant antenna and a simple 20 meter vertical. I picked the RGO one because all of the adjustments we had talked about in the classroom—AGC, Filters, A/B VFOs, Direct Frequency Entry, Pre Amp, Attenuation—are on the front panel and one button press away.

We hopped on the air with one of my students calling CQ single sideband on the 20 meter band. Her very first contact was with a station in Slovenia—and she simply beamed with excitement. All of my female students that term passed their Technician exam by the end of the term.

The RGO One is a very inviting radio.

I’ve had the luxury of testing, evaluating, and working with everything from one of the first prototypes to the latest updated version of the RGO One. It’s rare that I’m able to evaluate a radio over such a long period of time.

Even with the very early, bare-bones prototype, I was impressed with this transceiver’s performance characteristics. I’m not the only one either. It’s almost become routine new discussion group members join prior to receiving their radio, then announces how blown away they are with its performance. Check out eHam reviews, too—at time of posting, it’s a solid five stars at time of posting.

The RGO One reminds me of simple, classic radios of the 1980s and 90s, but underneath, it’s packing state-of-the-art performance.

Is it perfect? No radio is perfect, but I must say that for what it offers, it really hits the sweet spot for this radio operator. It’s a joy to use.

There are still features in the works that will either be implemented with future firmware updates, or with future boards. In terms of performance and appearance, it reminds me of the Ten-Tec Eagle and Elecraft K2—both benchmark rigs in my world. And like the Eagle and K2, the RGO One is happy in the field, at home, or even on a DXpedition. It’s a simple radio that beckons to be on the air.

If you’re interested in the Mission RGO One, check the following web page for the pre-order form and pricing list. The RGO One is produced in batches, so you’ll need to reserve your model.

Click here to view the Mission RGO One order page.

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TX Factor Episode 27

TX Factor – Episode 27:

Click here to view on YouTube or on the TX Factor website.

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Radio Waves: Arecibo Failure Caught on Video, Heathkit Employee Reminisces, Radio at 100 Series, and FCC to Require Email on Applications

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Arecibo Observatory’s 305-meter telescope in November 2020 (Credit: University of Central Florida)

Radio Waves: Stories Making Waves in the World of Radio

Many thanks to SWLing Post contributors Ned Wharton, Pete Eaton, Zack Schindler, and Dave Zantow for the following tips:

NSF releases footage from the moment Arecibo’s cables failed (ARS Technica)

Today, the National Science Foundation released video taken at the moment the Arecibo Radio Observatory’s cables failed, allowing its massive instrument platform to crash into the dish below. In describing the videos, the NSF also talked a bit about the monitoring program that had put the cameras in place, ideas it had been pursuing for stabilizing the structure pre-collapse, and prospects for building something new at the site.

A quick recap of the collapse: the Arecibo dish was designed to reflect incoming radio radiation to collectors that hung from a massive, 900-ton instrument package that was suspended above it. The suspension system was supported by three reinforced concrete towers that held cables that were anchored farther from the dish, looped over the towers, and then continued on to the platform itself. Failure of these cables eventually led to the platform dropping into the dish below it.

[…]The video of that collapse comes from a monitoring system put in place in the wake of the cable failures. Due to the danger of further cable breaks, the NSF had instituted no-go zones around each of the three towers that supported the cables. With no personnel allowed to get close enough to inspect the cables, the staff started monitoring them using daily drone flights, one of which was in progress during the collapse. In addition, a video camera was installed on top of the visitor’s center, which had a clear view of the instrument platform and one of the support towers.

Continue reading full article.

Heathkit: An Employee’s Look Back (Electronic Design)

Lessons of a successful electronic business—an interview with Chas Gilmore, former Heath executive.

For those of you who do not know or remember, Heath Company was the largest kit company in the world. Heath designed and put practically every type of electronic product into kit form. Its products, called Heathkits, were exceptionally popular and many are still in use today.

Over the years, Electronic Design has published many Heathkit-related articles and blogs. Recently, I had a chance to talk with Chas Gilmore, who was a Heath executive. For those of you who fondly remember Heathkit and miss its products, here’s a look back at this amazing company and the lessons it offers.

Chas, what was your affiliation with Heath?

A recent physics graduate, I joined Heath in 1966 as an engineer in the Scientific Instruments department. This was a new group designing laboratory instruments supporting the Malmstadt/Enke, Electronics for Scientists program. The kit business was making great strides.

The audio department was about to introduce the AR-15 FM receiver/amplifier. It had rave reviews, putting Heath in the top tier of the Audio/HiFi market. At the same time, the Ham (amateur radio) department was updating the phenomenally successful SB-line of an HF SSB receiver, transmitter, and transceiver, and modernizing the popular $99 single-band SSB transceiver line[…]

Radio at 100 & Roots of Radio Series (Radio World)

Zack writes:

Found this interesting series at Radioworld called “Radio at 100”. It is 29 different articles about the history of broadcasting in the USA. A lot of your readers might enjoy these;
https://www.radioworld.com/tag/radio-at-100

Another great series at Radioworld that your readers might be interested in “Roots of Radio”:

https://www.radioworld.com/columns-and-views/roots-of-radio

ARLB038 FCC to Require Email Addresses on Applications (ARRL Bulletin 38 ARLB038)

Amateur radio licensees and candidates will have to provide the FCC with an email address on applications, effective sometime in mid-2021.

If no email address is included, the FCC may dismiss the application as defective.

The FCC is fully transitioning to electronic correspondence and will no longer print or provide wireless licensees with hard-copy authorizations or registrations by mail.

A Report and Order (R&O) on “Completing the Transition to Electronic Filing, Licenses and Authorizations, and Correspondence in the Wireless Radio Services” in WT Docket 19-212 was adopted on September 16. The new rules will go into effect 6 months after publication in the Federal Register, which hasn’t happened yet, but the FCC is already strongly encouraging applicants to provide an email address.

When an email address is provided, licensees will receive an official electronic copy of their licenses when the application is granted.

The Report and Order can be found in PDF format online at, https://www.fcc.gov/document/fcc-adopts-electronic-licensing-report-and-order

Under Section 97.21 of the new rules, a person holding a valid amateur station license “must apply to the FCC for a modification of the license grant as necessary to show the correct mailing and email address, licensee name, club name, license trustee name, or license
custodian name.” For a club or military recreation station license, the application must be presented in document form to a club station call sign administrator who must submit the information to the FCC in an electronic batch file.

Under new Section 97.23, each license will have to show the grantee’s correct name, mailing address, and email address. “The email address must be an address where the grantee can receive electronic correspondence,” the amended rule will state. “Revocation of the station license or suspension of the operator license may result when correspondence from the FCC is returned as undeliverable because the grantee failed to provide the correct email address.”
NNNN
/EX[…]

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How to Build a Simple Linear-Loaded Dipole for Low-Noise Shortwave Radio Listening

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Many thanks to SWLing Post contributor and RX antenna guru, Grayhat, for another excellent guest post focusing on compact, low-profile urban antennas:

A linear loaded dipole for the SWL

by Grayhat

What follows is the description of an antenna which may allow to obtain good performances even in limited space, the antenna which I’m about to describe is a “linearl loaded dipole”(LLD) which some call the “cobra” antenna due to the “snaking” of its wires
The arms of the antenna are built using 3-conductors wire (which may be flat or round) and the 3 conductors are connected this way:

That is, connected “in series”, this means that, the electrical length of the antenna will be three times its physical one; this does NOT mean that the antenna will perform like a single wire of the same (total) length, yet it allows to “virtually” make it longer, which in turn gives it good performance even with relatively short sizes. Plus, the distributed inductance/capacitance between the wires not only gives it a number of “sub” resonance points, but also helps keeping the noise down (in my experience below the noise you’d expect from a regular dipole). At the same time it offers better performances than what one may expect from a “coil loaded” dipole. Plus, building it is easy and cheap and the antenna will fit into even (relatively) limited spaces (a balcony, a small yard and so on…).

Interested–? If so, read on and let me start by showing my (short – 9mt total) LLD installed on a balcony:

Here it is in all its “glory”–well, not exactly–I fiddled with it lately since I’m considering some mods so the tape isn’t correctly stuck and it has been raised and lowered quite some times, but in any case that’s it.

Bill of Materials

Here’s what you’ll need to build it (the links are just indicative, you may pick different stuff or buy it locally or elsewhere).

Some length of 3-conductors electrical wire which will fit your available space (pick it a bit longer to stay on the safe side), it may be flat or round, in my case I used the round type since it was easily available and cheap: https://amzn.to/3g2eZX3
A NooElec V2 9:1 BalUn–or, if you prefer you may try winding your own and trying other ratios. I tested some homebuilt 1:1, 1:4 and 1:6 and found that the tiny and cheap NooElec was the best fitting one): https://amzn.to/3fNnvce
A small weatherproof box to host the BalUn: https://amzn.to/33vjZy3
A center support which may be bought or built. In the latter case, a piece of PCV pipe with some holes to hold the wires should suffice. In my case I picked this one (can’t find it on amazon.com outside of Italy): https://www.amazon.it/gp/product/B07NKCYT5Z
A pair of SMA to BNC adapters: https://amzn.to/37krHwj
A run of RG-58 coax with BNC connectors: https://amzn.to/2JckHcR

Plus some additional bits and pieces like some rope to hang the antenna, some nylon cable ties, a bit of insulated wire, duct tape and some tools. Notice that the above list can be shortened if you already have some of the needed stuff and this, in turn will lower (the already low) cost of the antenna.

Putting the pieces together

Ok, let’s move on to the build phase. The first thing to do will be measuring your available space to find out how much wire we’ll be able to put on the air; in doing so, consider that (as in my case), the antenna could be mounted in “inverted Vee” configuration which will allow to fit the antenna even in limited space.

In any case, after measuring the available space, let’s subtract at least 1m (50cm at each end) to avoid placing the antenna ends too near to the supports. Also, if in “inverted Vee” config, we’ll need to subtract another 50cm to keep the feedpoint (center/box) away from the central support.

Once we’ve measured, we may start by cutting two equal lengths of 3-conductor wire. Next, we’ll remove a bit of the external sleeve to expose the three conductors and then we’ll remove the insulator from the ends of the three exposed wire (and repeat this at the other end of the cable and for both arms).

The resulting ends of each arm should look somewhat like in the example image below

Now we’ll need to connect the wires in series. We’ll pick one of the cables which will be the two arms of our antenna and, assuming we have the same colors as in the above image, we’ll connect the green and white together at one end and the black and green together at the other end. Repeat the same operation for the second arm and the cables will be ready.

Now, to have a reference, let’s assume that the ends of each arm with the black “free” (not connected) wire will go to the center of our dipole.

Leave the two arms alone for a moment, and let’s install the balun inside the waterproof box. To do so, we’ll start by cutting a (small) hole through the single rubber cap found at one side of the box, then insert the cap reversed, so that it will protrude to the inside of the box and not to the outside. Slide the balun SMA connector through the hole so that it will protrude outside the box.

Now use a marker to mark the balun position and remove the balun from the box. Pick a piece of wood/plastic or other insulating material, cut it to size (refer to marking and to balun size) and drill four holes matching the one found on the balun board. Slide four screws through the holes and lock them with nuts, the screws should be long enough to extrude for some mm. Now insert the balun in the screws using the holes present on the balun board and lock it with nuts (be gentle to avoid damaging the balun). At this point, add some “superglue” to the bottom of the support we just built, slide the balun SMA connector through the rubber cap hole we already practiced, and glue the support to the bottom of the waterproof box. Wait for the glue to dry.

Just to give you a better idea, see the photo above. That’s a photo of the early assembly of my balun. Later on, I rebuilt it as described above (but took no pics!), the image should help you understanding how it’s seated inside the box–by the way in our case it will be locked by the screws to the plastic support we glued to the box.

While waiting for the glue to dry, we may work on the dipole centerpiece.

If you bought one like I did, connecting the arm “black” (see above) wires should be pretty straightforward. If instead you choose to use a PVC pipe you’ll have to drill some holes to pass and lock the wire so that the strain will be supported by the pipe and not by the wire going to the balun box. In either case, connect a pair of short runs of insulated wire to the end (black) wire coming from each end. Those wires should be long enough to reach the balun wire terminal block inside the box.

Assuming the glue dried, it’s time to complete the feedpoint connection.

Bring the two wires coming from the centerpoint inside the waterproof box. Pick one of the wire terminal blocks which came with the balun (the “L” shaped one should be a good choice) and connect the wires to it. Then, slide the block in place until it locks firmly. After doing so, close the box and screw the SMA-BNC adapter onto the SMA connector coming from the balun. Our centerpiece and arms will now be ready, and will be time to put our antenna up!

I’ll skip the instructions about holding the arm ends and the centerpiece up, since I believe it should be pretty straightforward. Just ensure to put the antenna as high as possible and, if you have room make the arms as long as possible. In my case, due to my (self-imposed) limitations, the antenna was installed on a balcony. The arms have a length of about 3.5m each and the feedpoint (in the image above) sits at about 9m off the ground.

The more acute readers probably noticed those “blobs” on the coax, they are snap-on ferrite chokes I added to the coax (there are more of them at the rx end) to help tame common mode noise. I omitted them from the “BoM” since they may be added later on.

Anyhow, now that you have your LLD up it will be time to give it a test! In my case, I decided to start by running an FT8 session to see what the antenna could pick up during 8 hours, and the result, on the 20 meters band, is shown on the following map (click to enlarge):

Later, that same antenna allowed me to pick up signals from the Neumayer station in Antarctica–not bad, I think!

Some final notes

While running my “balcony experiment”, I built and tested several antennas, including a vanilla “randomwire”, a dipole, and a T2FD.

Compared to those, the LLD offers much less noise and better reception on a wide frequency range. By the way, it won’t perform miracles, but it’s serving me well on the LW band, on most ham bands, and even up to the Aircraft bands–indeed, was able to pick up several conversations between aircraft and ground air traffic control.

All I can suggest is that given a linear-loaded dipole is so simple, quite cheap, and may fit many locations, why don’t you give it a spin–? 🙂

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Review Notes: Xiegu GSOC Firmware updated to version 1.1–still a number of issues

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For those of you who have been asking about the new Xiegu GSOC controller, I just updated my unit with the latest firmware (version 1.1).

Firmware notes show that it addresses the following items:

Xiegu GSOC FW V1.1
1. Solved the CW sidetone delay problem
2. Solved the problem of unstable system and occasional crash
3. Added RTTY modem
4. Added CW decoder
5. Added SWR scanner
6. Added FFT/Waterfall level adjustment
7. Added FFT line/fill color mixer

The list above was copied directly from the version notes.

I’m currently evaluating the GSOC/G90 pair which were kindly sent to me on loan by Radioddity. I upgraded the GSOC firmware to v1.1 this weekend.

What follows are some of my evaluation notes an observations after performing the upgrade.

Updating firmware

Updating the GSOC firmware is a pretty straight-forward process.

First you must download the GSOC firmware package (about 330 MB!) which includes a disk image and application to flash the image to a MicroSD card.

Yes, you’ll need a dedicated MicroSD card to upgrade the GSOC firmware–meaning, you can’t simply use a MicroSD card with data on it you’d like to keep because the process of flashing the ISO file also includes a full format with multiple partitions.

You’ll also need an SD Card reader/writer if your Windows PC doesn’t include one.

The included firmware application/tool makes it quite easy to flash a disk image on the MicroSD card.

After the MicroSD card has been prepared, simply turn off the GSOC, insert the MicroSD card on the left side of the GSOC, turn it back on and the GSOC will automatically boot from the MicroSD card and install the new OS/firmware.

Once the upgrade has completed, the GSOC will turn itself off and you must remove the MicroSD card.

If you want to restore the MicroSD card to one partition, you’ll need to perform another format and shrink the volumes.

CW sidetone latency (still issues)

After performing the upgrade, I hopped on the air and tried to make a few CW contacts since I noted in the version notes that the CW sidetone latency had been addressed. So far, my evaluation has pretty much been on hold because I’m unable to use CW mode with any sense of sending accuracy.

Unfortunately, I’m still finding that there’s still a bit of sidetone latency or keyer timing interfering with my ability to correctly send words and letters.

To my ear, it sounds like there’s much less latency in the sidetone audio now (compared with v1.0 which was a little insane) but I still struggle sending characters that end in a string of dits or dashes. For example, when I try to send a “D” the radio will often produce a “B” by adding one extra dit. Or if I try to send a “W” it might produce a “J”. I know something is a little bit off because I botched up two CW contacts with POTA stations yesterday as I tried to send my own callsign correctly. And “73” was even problematic.

I’m guessing that there may still be a bit of audio lag between the G90 body (where the CW key is plugged in) and the GSOC (where the sidetone audio comes out). At the end of the day, the keying information must be sent to the GSOC from the G90 transceiver body and I assume the processor on the G90 is causing a bit of audio latency. Hopefully, Xiegu can sort this out. It’s a serious issue for anyone who wants to operate CW with the GSOC.

If you own the GSOC and operate CW, I’d love your comments and feedback.

Other updates

I tried using the CW decoder yesterday via the “Modem” menu and had limited success decoding a CW rag chew.

My markup in red: You can see at the very end of this conversation, it decoded the call sign, but interpreted “TU” as “TEA”

The decoder seemed to adjust the WPM rate automatically at one point, but as you can see in the image above, almost every dit was interpreted as an “E” and every dash a “T”. I must assume I don’t have it configured properly, but I don’t have an operator’s manual for reference and instruction. I’ve also tried RTTY decoding, but haven’t been successful so far–I’m pretty sure this is also because I haven’t configured it properly.

SWR Scanner

I tested the new SWR scanner and it seems to work quite well, plotting SWR across a given frequency range. I did note, however, that it doesn’t seem to confine itself to the ham bands at all. It does inject a signal as it scans (I read 1.5 to 2 watts on my CN-801 meter).

I discovered out-of-band scanning when I took the photo above while trying to do a scan of the 30 meter band. It started around 9.6 MHz–well into the 31M broadcast band where it shouldn’t be transmitting. Xiegu needs to limit transmitted signal to the ham bands.

Memory Keying

I had hoped Voice Memory Keying would be added along with TX/RX recording. I do believe this will eventually be included in a future update. It appears via the “Modem” menu that CW Memory Keying has been added, but I can’t sort out how to make it work (again, a operation manual would be quite handy).

Audio recording

I had hoped transmit and received audio recording would be added in this firmware update; I understand this will eventually be added.

Combined current drain

As I mentioned in a previous GSOC update, the GSOC controller and G90 transceiver both need a 12V power source–indeed, each has a dedicated power port. The GSOC does not derive power from the G90.

I was originally told that the G90 and GSOC both pull about .60 amps in receive which would total 1.2 amps combined. My Hardened Power Systems QRP Ranger battery pack displays voltage and current; it’s not a lab-grade measurement device, but it’s pretty accurate. When I operate the GSOC and G90 at a moderate volume levels in receive, it appears to draw 0.95 to 0.97 amps–basically, 1 amp.

At home on a power supply, this is inconsequential, but in the field you’d need to keep this in mind when choosing a battery. It’s on par with a number of 100 watt transceivers.

Spectrum display images

I’m still finding images on the GSOC display that are not present in the received audio. I mentioned this in my initial overview and it doesn’t seem the firmware update addressed this.

I can only assume the spectrum imaging might be due to the I/Q input being too “hot” coming from the G90 via the shielded audio patchcord. Perhaps there’s a function to manually lower the I/Q gain, but I haven’t found that yet.

Spectrum images are most noticeable on the 31 meter band, but found them on the 20 meter ham band as well.

Here are two screen shots that show how images appear when a nearby signal overwhelms the GSOC:

Images are not present all of the time, only when a strong signal intrudes.

Ever-present noise and spurs in portions of spectrum

Perhaps this is related to the issue above, but there are some spurs on the spectrum display that seem to be present whether the G90/GSOC is hooked up to an antenna or dummy load.

Here’s a photo of the GSOC hooked up to an antenna:

And to a dummy load:

I’ve highlighted the spurs in red and as you can see, the intensity is stronger without an antenna thus I’m guessing this is internally-generated. The spurs do not move on the display as you change frequency.

Other notes

Again, I feel like the GSOC firmware isn’t mature and I can’t yet recommend purchasing it. I feel like Xiegu have rushed this unit to market.

I know that, over time, more features will be added and Xiegu certainly has a track record of following up.

When I evaluate a product, I keep a list of notes that I send to the manufacturer and to keep for my own reference. In Alpha and/or Beta testing, I’d share this info only with the manufacturer. Since the GSOC is a product that’s in production and widely available, however, I thought I’d share them here publicly:

GSOC volume control scale is 0 to 28. The difference between 0 (muted) to 1 seems to be the biggest increment. Volume 1 is actually a low to moderate volume level (i.e. a bit high).
Boot up time for the GSOC is 30 seconds
A keyboard and mouse or capacitive stylus are almost required for accurate operation. Many of the touch screen buttons are quite small and difficult to accurately engage with fingertip. The pointer seems to fall slightly below where fingertip makes contact on the screen.
Notch Filter seems to have no effect even after the v1.1 upgrade. There is no Auto Notch feature either.
I can’t seem to engage split operation even though there are A/B switchable VFOs and a “Split” button above the spectrum display. Using a keyboard and mouse doesn’t engage it either.
There are a number of announced features that I haven’t discovered including some WiFi and Bluetooth wireless functionality.
For field use, you must pack quite a bit of kit: the transceiver, the controller, CW key cable, microphone, serial cable, I/Q cable, G90 Power cable, and GSOC power cable. It would also be advisable to take a wireless keyboard and mouse especially if you plan to use any advanced functions like CW memory keying.
It doesn’t appear that you have CAT control of the GSOC which complicates digital operation. I believe many of us hoped the GSOC would make digital mode operation easier with the G90, but it hasn’t. Indeed, I assumed the GSOC would have an internal sound card for digi modes much like the Icom IC-7300 and IC-705. Use of VOX control is still the best way to control transmit. I hope this can be upgraded else this would be a missed opportunity.
Since the v1.1 upgrade, the GSOC hasn’t crashed (it did frequently with the v1.0 firmware).
Not a pro or con, but I wish the AF Gain/Squelch was AF Gain/RF Gain like most HF transceivers. I’ve accidently engaged squelch twice which essentially muted audio. Pressing and holding the PO (Power Output) button opens the RG Gain control function).

The GSOC Universal Controller is an interesting accessory for the G90 and I’ve read comments from users that love the interface and added functionality.

If I’m being honest, I feel like I’m Beta testing the GSOC. I’ve yet to find a GSOC operation manual–this makes it very difficult to know if one has correctly configured the controller and engaged features/functions correctly. A quick start guide is included with the product, but it really only helps with connections and starting up the GSOC the first time. If you’re a GSOC early adopter, just be aware of this. Again, I’m pretty confident Xiegu will make refinements and include promised features in future firmware updates. I understand their software engineer closely monitors the GSOC discussion group as well. If you’re considering the purchase of a GSOC, I’d encourage you to join the GSOC group.

Questions? Comments?

As I said, I can’t recommend purchasing the GSOC controller yet. So much can change with firmware updates, however, I would encourage you to bookmark the tag GSOC to follow our updates here on the SWLing Post. I will update the GSOC controller each time a new firmware version is issued and until Radioddity asks for the loaner units to be returned. Again, many thanks to Radioddity for making this GSOC and G90 evaluation possible.

Feel free to comment with any questions you might have and I’ll do my best to answer them!

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