Category Archives: Ham Radio

Icom IC-705 Blind Receiver Test #3

Test #3: Shannon Volmet SSB

In this third test (click here for #1 and here for #2)) we’ll listen to the Icom IC-705, and one other comparable radio, tuned to Shannon Volmet on 8,957 kHz.

I’ve done my best to match these radios in terms of audio and receiver settings, but it’s certainly not perfect–these are essentially real world, not laboratory conditions.

Notes:

Both radios are using the same antenna via my ELAD ASA15 Antenna Splitter Amplifier
Both radios are set to the same bandwidth: 2.4 kHz
I’ve tried to match AGC settings on all radios
Both radios have different audio EQ characteristics–not all are fully adjustable
Both have separate recording devices and are not matched perfectly in terms of audio levels. In other words, you may need to adjust your volume a bit to compare.

My advice would be to focus on aspects like signal intelligibility, selectivity and signal to noise.

Please listen to each recording, then kindly answer and submit the survey below. Thank you!

Radio A

Radio B

Survey
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Icom IC-705 Blind Receiver Test #2

Test #2: 40 meters CW

In this second test (click here for #1) we’ll listen to the Icom IC-705, and one other comparable radio, tuned to a 40 meter CW station. Each recording is roughly the same length (2 minutes).

I’ve done my best to match these radios in terms of audio and receiver settings, but it’s certainly not perfect–these are essentially real world, not laboratory conditions. Indeed, making these recordings comparable in CW is incredibly challenging as the mode is so incredibly narrow and challenging to zero beat with radios that can tuned so precisely.

Notes:

Both radios are using the same antenna via my ELAD ASA15 Antenna Splitter Amplifier
Both radios are set to the same bandwidth: 0.5 kHz
I’ve tried to match AGC settings on all radios
Both radios have different audio EQ characteristics–not all are fully adjustable
Both have separate recording devices and are not matched perfectly in terms of audio levels. In other words, you may need to adjust your volume a bit to compare.

My advice would be to focus on aspects like signal intelligibility, selectivity and signal to noise.

Please listen to each recording, then kindly answer and submit the survey below. Thank you!

Radio A

Radio B

Survey

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Participate in our Icom IC-705 Blind Receiver Test #1

I’ve been asked by a number of readers to do a blind audio/receiver test of the new Icom IC-705 transceiver. I’m happy to say I’ve started the process today.

Instead of publishing one long survey with multiple types of recordings (AM, SSB, CW, etc.) as I’ve done in the past, I’ve decided to create a post for each test. This will make the process of completing the survey much easier. Additionally, it won’t require that you respond to each test in order to submit your pick.

Test #1: 40 meters SSB

In this first test we’ll listen to the IC-705, and two other radios, tuned to a weak 40 meter station in lower sideband (LSB) mode. Specifically, this is ham radio operator W3JPH activating Shikellamy State Park in Pennsylvania for the Parks On The Air program. I like this test because it includes 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. Each recording is roughly the same length (5 minutes).

I’ve done my best to match these radios in terms of audio and receiver settings, but it’s certainly not perfect–these are essentially real world, not laboratory conditions.

Notes:

All radios are using the same antenna via my ELAD ASA15 Antenna Splitter Amplifier
All radios are set to the same bandwidth: 2.4 kHz
I’ve tried to match AGC settings on all radios
All three radios have different audio EQ characteristics–not all are fully adjustable
All three have separate recording devices and are not matched perfectly in terms of audio levels. In other words, you may need to adjust your volume a bit to compare.

My advice would be to focus on aspects like signal intelligibility, selectivity and signal to noise.

Please listen to each recording, then kindly answer and submit the survey below. Thank you!

Radio A

Radio B

Radio C

Survey

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RSGB Convention is live Saturday, October 10, 2020 until 17:00 BST

Stream 1

Stream 2

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The perils of radio self-enabling…

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So the SWLing Post has been online now for twelve years and during that time I’ve been accused of being a “radio enabler.” Of course, I’ve never counted just how many, but I’m guessing somewhere in the region of 115,900 times.

Truth is, radio love is infectious.

In the past, I’ve read reviews and articles about radios that have lead me down the path to making a purchase. Countless times.

Yesterday, though, I quite literally enabled myself.

It all started with the Elecraft KX1

I posted this article on QRPer.com where I listed four ham radio transceivers I regretted selling. The number one pick was the Elecraft KX1 QRP CW transceiver.

I owned the KX1 for years. It was my first CW-only transceiver and my fist backpack-friendly radio for proper lightweight, low-impact, field radio fun. I sold it in 2016 to help fund the purchase of my Elecraft KX2.

Besides simply admiring a radio that embraced the philosophy of “form following function,” the KX1 had features you wouldn’t expect in a radio so compact and so lightweight. For example…

SWL Band RX

Wayne Burdick (N6KR)–co-founder and engineer/designer at Elecraft–is a shortwave radio enthusiast.

The KX1 was designed so that while you’re camping, hiking, or activating a SOTA site, you can also do a little SWLing!

Even though the KX1 is a CW-only rig in transmit, they added both LSB and USB out-of-band reception. Depending on the KX1 band configuration, you can zero-beat broadcasters, widen the adjustable filter, and enjoy shortwave listening in the field.

When I owned the KX1, I did this quite often. Don’t get wrong: it couldn’t compete with, say, a dedicated shortwave receiver like the Tecsun PL-680, but it worked well enough that listening to even weaker stations was very doable. When one-bag travelling or camping, it was great to have one radio that could serve two functions.

LED Log Book Lamp

Photo: Eric (WD8RIF)

To my knowledge, the KX1 is the only portable transceiver I know of that includes a built-in logging lamp.

I remember once operating the KX1 on the beach at Jekyll Island, GA one evening and using the lamp to illuminate my logging sheet. Good times…

Perfect ergonomics for winter field operating

Elecraft KX2 (top) and KX1 (bottom)

Even though the KX1 is a small radio, it was one of the first field rigs to have top-mounted controls. All of the buttons, knobs, and pots are well-spaced and easy to access. I especially love the pots used for the RF Gain, Filter, and AF Gain–raised, thin, tactile stems, essentially, that could be easily adjusted even while wearing thick winter gloves.

In fact, the KX1 is the only portable radio I’ve ever operated that didn’t require me, at some point, to remove my gloves.

Insane amount of features

In true Elecraft fashion, the KX1 packs a ton of features specifically designed around field operation. Check out the features from their quick reference sheet above.

Here’s what happened

I published my article on QRPer.com and decided, on a whim, to see if there were any listings for the KX1 on QTH.com’s classifieds list via my QRP Transceiver shopping list.

One ham had a KX1 listed. It was nearly identical to the one I owned and even included the same Pelican case. The only difference was my KX1 sported 4 bands (80, 40, 30, and 20m)–this one only had three bands (40, 30, and 20). Not a big deal because typically when I’m hiking I do little operating on 80 meters. If I decide to add 80 meters, I may still be able to snag the appropriate kit module.

The listing had no price.

I called the seller–who turned out to be fairly local–and within an hour he came back with his offer: $300 for the entire kit plus true shipping costs. I thought that was a fair price, so I purchased it and he even shipped it same day.

Moral of the story?

Next time I make a post about radios I’ve regretted selling, trading, or giving away, I need to publish it, then slowly back away from the computer.

I’m not going to be too hard on myself this time, though: I’m truly looking forward to putting the KX1 back in rotation here at SWLing Post HQ.

If you feel inclined, I would encourage you to comment on this post about radios you’ve regretted selling (click here to read the full QRPer post). I love hearing why specific radios have strong appeal for certain enthusiasts.

Just take my advice and stay away from the classifieds!

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Radio Waves: Signals from Mars, Two More Hamstronauts, M17 Digital Voice Mode, and Climbing Trees for a Better Signal

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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 Troy Riedel, LG, Ron and the ARRL News for the following tips:

Radio Signals from Mars (Spaceweather.com)

How close is Mars? Close enough for radio reception. On Oct. 4th, amateur radio operator Scott Tilley picked up a carrier wave from NASA’s Mars Reconnaissance Orbiter (MRO) circling the Red Planet. Turn up the volume and listen to the Martian Doppler shift:

Tilley is a leader in the field of satellite radio. Dead satellites, zombie satellites, spy satellites: He routinely finds and tracks them. “But this was a first for me,” he says. “A satellite around Mars!”

It’s not easy picking up radio signals from distant planets. NASA does it using the giant antennas of the Deep Space Network. Tilley uses a modest 60 cm dish in his backyard in Roberts Creek, BC. This week’s close encounter with Mars set the stage for his detection.

“MRO’s signal is weak, but it is one of the louder signals in Mars orbit,” says Tilley. “The spacecraft has a large dish antenna it uses as a relay for other Mars missions. With the proximity of Mars these days, it was the perfect time to try.”[…]

Two More Astronauts Earn Amateur Radio Licenses (ARRL News)

Although the lockdown of Johnson Space Center (JSC) postponed amateur radio training and licensing over the past 7 months, NASA ISS Ham Project Coordinator Kenneth Ransom, N5VHO, was able to work with all of the new astronaut-class graduates, as well as offer some refresher courses with already-licensed astronauts. Licensed astronauts on the International Space Station (ISS) may operate the on-station ham radio equipment without restrictions.

Astronauts often participate in Amateur Radio on the International Space Station (ARISS) contacts with schools and groups on Earth.

NASA Astronaut Kayla Barron, who completed her introductory course in June and received basic ham radio operations training in late September, recently tested and received the call sign KI5LAL.

European Space Agency astronaut Matthias Maurer passed his amateur radio exam on July 30, and he got his basic ham operations training in July. He now is KI5KFH.

Astronauts Shane Kimbrough, KE5HOD, and Shannon Walker, KD5DXB, completed the refresher course earlier this year. Two other new astronauts are in the queue to take the Technician license exam. — Thanks to Rosalie White, K1STO[…]

M17 Aims to replace proprietary ham radio protocols (Hackaday.io)

While M17 might sound like a new kind of automatic rifle (as actually, it is), we were referring to an open source project to create a ham radio transceiver. Instead of paraphrasing the project’s goals, we’ll simply quote them:

The goal here should be to kick the proprietary protocols off the airwaves, replace DMR, Fusion, D-Star, etc. To do that, it’s not just good enough to be open, it has to be legitimately competitive.

Like some other commercial protocols, M17 uses 4FSK along with error correction. The protocol allows for encryption, streaming, and the encoding of callsigns in messages. There are also provisions for framing IP packets to carry data. The protocol can handle voice and data in a point-to-point or broadcast topology.

On the hardware side, the TR-9 is a UHF handheld that can do FM voice or M17 with up to 3 watts out. The RF portion uses an ADF7021 chip which is specifically made to do 4FSK. There’s also an Arm CPU to handle the digital work.[…]

Armed with a radio, Cambodian girl climbs tree to access education (SE Asia Globe)

When Cambodian schools closed due to Covid-19, poor internet access and a lack of minority language materials made distance learning in rural communities near impossible. But armed with a simple radio, children are rising above these obstacles to their education

Jumping down from the tree near her home, Srey Ka assumes her spot in the shade underneath as she adjusts the dials on her radio. Her pet piglet remains asleep at her feet, twitching his nose as he dreams, his belly full of leftover rice. Around her, cows meander by, their ringing bells competing with the sound of static from her radio.

While her school is still closed due to Covid-19 regulations, she still wears her Grade 3 uniform as she attempts to locate a signal. She’s listening out for distance learning programmes – six hours of educational radio broadcasts per week for children in Grades 1-3, some of which are in her ethnic minority language.

It was August and Srey Ka had just received a radio from international nonprofit Aide et Action, two weeks before her school reopened as pandemic measures eased in Cambodia in early September.

From the Phnong ethnic minority group, Srey Ka struggled to find learning resources in her language during school closures. Eager to cram as much as she can before returning to school, Srey Ka tied the antenna of her radio to the highest point of a tree to get the best reception. Even a clear radio signal is hard to come by in the small fishing village of Pun Thachea, located along a remote stretch of the Mekong river in Cambodia’s northeast Kratié province.[…]

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Steve tracks down the source of persistent radio interference and gets it addressed

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Photo via Unsplash

Many thanks to SWLing Post contributor, Steve Allen (KZ4TN), who shares the following guest post:

Tracking Down Radio Frequency Interference

by Steve Allen, KZ4TN

I first noticed the RFI in late November 2019 as a steady buzz at around S9. It was present over most of the high frequency spectrum. I waited until the second week of December to see if you would end on its own, no such luck. I put an HF rig in my truck and started driving around the area to see if I could find a potential source. About a quarter mile from my home is a 161 KVA substation operated jointly by the Tennessee Valley Authority and my local electrical utility. When I parked in the driveway outside of the gated substation the sound of the interference was very strong and blanked the HF spectrum. I called the phone number on the gate and after an explanation of why I was calling I was connected to a fellow radio operator. I explained the situation and he said he would bring the issue to someone’s attention and get back to me.

A week went by and I didn’t hear back from the TVA. I called the person I spoke with previously and he said that the individuals that he spoke with questioned the validity of my findings. He was very helpful but said he didn’t have much clout with the TVA, RFI investigations were not his area of responsibility. I told him I would be happy to meet with someone from the TVA and show them what I had found. I also said I would contact my local electric utility and see if they had an RFI detector so we could eliminate their equipment. My initial contact at the TVA said he would keep trying to get someone to take this issue on and work with me to investigate. I said I would call him back next week.

I then called the local utility company and talked to someone there who was familiar with these kinds of issues. The local utility company owns the output side of the equipment at the substation. He told me he was going to perform an infrared (heat) inspection of their equipment at the substation mid January as part of their annual maintenance and will also check the low voltage utility lines near the substation. I told him that I didn’t notice this RFI until after they had a power outage nearby. He said he would try and get over earlier and check the power lines that run along the streets and look into the power outage history for this area.

All during this time I kept a daily log of the RFI including time of day, frequency effected and S unit level. I also logged the weather conditions. To eliminate the electronics in my house as a possible source I connected my transceiver to a 12 VDC battery and shut off the mains circuit breaker, the RFI did not change at all. I also visited the ARRL webpage that provide information on RFI including recordings of known RFI:

http://www.arrl.org/radio-frequency-interference-rfi

The ARRL is the best source I have found in finding and fixing RFI.

By December 27th, no word back from anyone. I assumed that they were off for Christmas but decided to write a letter to the TVA as a follow up to what had happened so far. In early January I received and email from one of the TVA engineers who said he would contact a field engineer who would contact me. The next day I received an email from the field engineer who said he was going to be in the area on another job but would meet me at the substation.

So, of course as soon as I am making headway with finding the problem the RFI diminished to the point of not being a problem. By this time here in Northeast Tennessee the winter temps are in the 40s and the humidity is lower. For whatever reason, the RFI ended. I met with the field engineer and we agreed that if there is no RFI there is nothing to search for.

Fast forward to August, 2020. In June and July I had been operating digital, mostly FT8. I usually had the volume control at zero and as it was summer I was doing no shortwave listening. One day I decided to tune around the bands and found that the RFI was back as strong as it was during December at S4-S9 from 2-30 MHz. I emailed the principal engineer I had previously been in contact with at the TVA and he told me he would contact another field engineer and that he would come to my house with an RFI locator and start a thorough investigation. The next day I received an email from the field engineer and we scheduled a time for him come over.

Upon his arrival he connected his RFI locator to my vertical antenna and tuned across the spectrum. The locator immediately displayed the signal. He captured an electronic image and said that he could now drive around the area and try and find a match. A hour and a half later he called and said he was unsuccessful and wanted to come back and make sure the signal was still present. Sure enough, it still displayed on his locator and he was puzzled why he could not find a similar signal while driving the area. He said he would send a copy of the recording to the TVA engineer and get back to me.

A few days later I heard back from him and he wanted to come over again and make another recording. I believe after discussing this issue with his supervisor he was going to use a different method of searching the area. After a couple of hours I received a phone call from the field engineer telling me that he thought he had found the source of interference. Using a parabolic antenna he had found two different utility poles that appeared to have defective lightening arrestors on them. Both are within a quarter mile of my QTH. These poles are the responsibility of the local electrical utility not the TVA. He said he would contact them and follow up with me in a few days.

In a couple of days the interference was very low to nonexistent. Shortly thereafter the engineer contacted me saying the local utility company had completed the repairs and wanted to know if the interference was still present. I said I hadn’t hear it in a couple of days and I would get back to him if it returned. A couple of weeks later I received an email from the field engineer detailing the incident, what he had done to locate the interference, and what was done to repair it. In his email he stated the service was provided at no cost by the TVA Right of Way and Elizabethton Electric Department through TVA’s Comprehensive Services Program (CSP). I am so appreciative of the Tennessee Valley Authority. The airwaves are now free of manmade interference and I am looking forward to another winter of operating and listening to shortwave radio. Here in the 21st century there are so many electronic devices that are capable of causing RFI. I am very thankful that my station is RFI free (for the time being).

Steve Allen, KZ4TN
Elizabethton, TN

Thank you so much for sharing your story, Steve. Only recently, we posted Emilio’s article about tracing interference to poorly made switching power supplies. Thank you for sharing how you approached your local utility company, in your case, to resolve your RFI!

Very encouraging! Readers note that you don’t always have to live with persistent RFI. If you know the source isn’t coming from within your home, sometimes it’s simply a matter of getting your local utilities company to investigate.

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