Category Archives: Guest Posts

Guest Post: Patrick compares four receivers

Many thanks to SWLing Post contributor, Patrick Canler who writes to us from France and shares the following guest post which he translated into English:

The number of receivers on the market is quite large, and all are sold to be the “best”. I have thought it useful to compare materials using them in the shack as a neophyte SWL; going beyond the features in the brochures to talk about everyday utility. This article does not pretend to do “scientific” testing of the four receivers–skills and special equipment are needed and some specialized laboratories already do it.

The four receivers cover thirty years of electronics manufacturing; four different brands with their own technology and specifications. Over such period, technologies and innovations have evolved. One of the questions I had was: “Does efficiency give any receiver an advantage?”.

The Contenders:

NRD-535 from Japan Radio Company.

A reference of the 90s! It received 5 stars from WRTH (which publishes annually the almanac “World Radio and TV Handook”). The NRD-535 has conventional construction with an electronic card per function and discrete and analog filters.

This is a home station receiver, weighing in at 10 kg. The NRD-535 ceased to be produced in 1996, and its value second hand is growing due to its reputation.

AR7030 from AOR

Designed by the engineer who developed the LOWE receiver line, the AR7030 is also famous for its reception. It uses special ergonomics and a hybrid of software menus and conventional controls. Quite small, it is easily transportable, due its design that already uses SMC but keeps the analog filters.

IC-R75 ICOM

Modern device, classical format and renowned–the R75 is the only receiver tested that is still in production [Note: it was recently removed from production]. It uses CMS, combines analog and DSP filtering (the DSP option is present on the device under test). Its ergonomic design is intuitive and so too are controls and menus.

1102S RADIOJET Bonito,

The 1102S RADIOJET is the only unit in this comparison that is produced in Europe!
The Radiojet includes the latest developments in technology, its performance is simply stunning on the data/spec sheet. The application includes many tools (spectrograph, digital filters, IF and AF recorders, decoder, list of broadcast stations, etc.). It brings together all the SMC receiving electronics in a small box that can fit in a pocket.

The commands and tools are assigned to a software (highly evolved) that runs on the PC which is connected the SDR. The power of the PC also brings graphics, memory, recordings etc.

Why these four rigs?

In the beginning, and it was it which led me to be SWL, I acquired the RADIOJET based on its announced characteristics: sensitivity of “secret services”, adaptable to all cases with filters, graphics tools–“Star Wars equipment” is not it! Later I learned about 50 MHz and at the same time I was struggling to exploit the Radiojet SDR.

A good opportunity to purchase an ICOM R75 brought me back to conventional radio ergonomics. As time passed, I felt my listening skills improved with these 2 receivers and the receiver syndrome grew! A Kenwood R5000 joined the others for its VHF potential and HF reputation.

Then I discovered an NRD-525 on Ebay at a fair price point (rare)–it joined the group of receivers. The latter two were sold and replaced respectively by an AOR 7030 and by NRD-535. I really enjoyed the 525, but the 535 is even better.

In use, the RADIOJET and R75 have always posed problems with settings and sound quality. Kenwood reassured me about the fact that we could get some nice reception without fighting against the controls. validated by the AOR, the NRD 525 & 535. Perhaps I did not understand the manipulation of digital filters???

Now to the shack!

The four receivers are placed side by side, but arranged so as not to disturb each other (eg. the display of the ND535 disrupted the RADIOJET).

The antenna is a 25m random wire oriented East/West with 9:1 balun and its own ground. The passage from a receiver to the other is done by a conventional antenna switch.

All the tests were performed in one evening for constant conditions, there was a fairly present QRM which, was not too bad for comparison purposes. The tests were made in SSB or AM. Preliminary tests had shown that the results in digital modes (PSK31, JT65, ..) relied more on the decoder performance of the PC rather than the receiver. The tests increased from the lowest frequency detected this evening (Europe 1-163 kHZ) to the highest (Foreign Broadcast =15,545 MHz).

The highest frequencies, up to 30 MHz, were deserted in phone, at least for my installation.
The procedure was:

Signal is detected from the spectrograph SDR: it typically “sees” almost inaudible signals.
The candidate frequency is tuned on all four receivers
I listening to all of the signals on all receivers, seeking to get the maximum performance, using all possibilities (notch, passband, IF Shift, integrated amplifiers, attenuator, etc.)
Results are reported in the table below.

One can notice rather quickly:

that age is not a handicap
the number of functions is not always an advantage

1102S RADIOJET
Performance and capabilities above the rest (on paper) and requires being connected to a PC. At the present time, on an old Celeron 2Gb ram, the RadioJet’s application never saturated the CPU. The band spectrum display allows one to find the QSO, to filter theoretically perfectly, but it does not always equate to the understandability of the signal or give a pleasant audio. And the number of software features and functions complicates the signal manipulation. The sound is still a little metallic, perhaps due to the signal processing software. Its small size makes it a unbeatable mobile receiver for travel, functions are incredibly useful for those who master the RadioJet application.
AOR AR7030
Inherently simpler at face value–the AR7030 is ultra easy to use. It makes it easy for the user to find and tweak a candidate signal. It’s intuitive and has essential functions only. It has well-designed electronics. The AR7030 is also best receiver tested for handling strong signals without overloading (broadcasts stations or nearby hyper-kilowatted amateur radio operators) which seems to prove that it is designed for these stations. Its limit is the lack of adaptive notch filter types to clean the noise, which is still quite present when the QRM is there. (The newer version 7030+ has added features to help). Finally, it is the smallest stand-alone, portable and with 3 options of antennas connections.
ICOM R75
The R75 climbs up the frequency band all the way to 50 MHz, the only receiver tested with this frequency range. It enjoys an excellent reputation, and can be equipped with a DSP (digital signal processing) on audio. The DSP provides adaptive noise reduction and automatic notch, but has a relative effectiveness which is not always successful in clarifying the signal. Sometimes it adds an unpleasant “rattling”. In use, the interface is pretty intuitive–mixing commands by buttons and menus. Twin pass band tuning (PBT) is effective and allows for IF Shift and/or notch. The speaker is (very) small and gives an aggressive/harsh sound. This receiver is relatively small in size and lightweight. It has a mobile stand and is designed for a 12-14V power supply.
JRC NRD-535
The NRD-535 is the oldest tested–indeed, it was already discontinued before the other receivers were in production. A solid and reliable construction, good ergonomic with conventional front panel controls, good sensitivity, and a decent sized speaker have earned it status as a benchmark in its time. Very sensitive, it extracts the signals and, once found the right filter, gives it pleasant audio. Some signals are not completely cleaned but it does rarely less than others. The NRD-535 is designed for home use: it is heavy, almost 10 kg, and is contains several circuit boards which should not be too exposed to excessive shocks, especially considering they’re over 20 years old.

Summary

My ranking is as follows:

JRC NRD-535 for its ease of use and ability to dig out a usable signal from the QRM.
AOR AR7030 for its simplicity, portability and the fact that it extract good sound/audio quickly, even if a little noisy at times.
Bonito RADIOJET for its small size and its extensive feature set. It is ultra-mobile with a laptop.
ICOM R75 does the job and covers a wide frequency range. But lags in performance relative to the other receiver tested, with a “nasal” sound and a DSP that does not keep its intended promises.

About digital filters: the SDR and ICOM have them, the possibilities are extensive and allow adaptive filtering that others do not with analog filters. By cons they give a dry sound and sometimes add “snap” under whistles. Listening is overall less pleasant in comparison.

Receivers Advantages + / Disadvantages –

Bonito RADIOJET
+ Top technology, visual and many new features over the others on this point
– Complicated, metallic sound, emphasizing the sometimes painful receiver interaction with a computer mouse

Icom R75
+ Great value at the present time
– Audio and imperfect signal cleaning

AOR AR7030
+ Simple and effective
– Ideal companion if it had a notch filter: noise is present

JRC NRD-535
+ Effective sensitivity and clean audio
– Older technology, less portable

Note that this is a personal opinion: a computer geek will certainly get the most of performance and possibilities from an SDR like the Bonito RadioJet.

The NRD-535 shows its age, will one day reach the end of its useful life despite its robust construction. ICOM can cover up to 6m remaining mobile and has a good filter possibilities (DSP). The AOR is easy, fast and gives a correct listening, general purpose. It is the only one to pass the VLF.

The ideal then?
* RADIOJET for sensitivity,
* The RADIOJET for tools/features and functions
* AR7030 for the lower bands
* Icom for the higher bands
* NRD-535 for ergonomics
* AOR for portability

Personally, I use the NRD-535 for DXing (due to superior audio), the AR7030 for digital modes,
the RADIOJET to visually search for signals, and to sometimes clarify the signal even better and because it’s ultra-mobile and always in my PC case.

73,
Patrick F61112

Thank you, Patrick!

I should mention that I think you did a fine job translating your article into English for us! I would not be as successful writing an article in French!

I’ve never owned a JRC of any sort. If I ever found an NRD-535 for a good price, I would purchase one without hesitation. I’ve never spent much time on the AR7030 either. It’s simple “Lowe-like” front panel is quite appealing for field use. I found that the RadioJet audio is quite nice when paired with a good set of headphones.

Alexander’s report from Ham Radio Friedrichshafen

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The Friedrichshafen exhibition grounds. (Photo: Ham Radio Friedrichshafen)

Many thanks to SWLing Post contributor, Alexander (DL4NO), who shared a few notes with me from his visit at the Friedrichshafen Ham Radio convention. Alexander has kindly allowed me to post his notes here on the SWLing Post. Alexander writes:

The first booth I visited was of Dokufunk (http://www.dokufunk.org/). They collect QSLs and other information about wireless history for scientific evaluation. Its head Wolf, OE1WHC, was a moderator for the Austrian shortwave service which does not exist anymore. But ORF still supports Dokufunk. They have a large archive and even the equipment to digitize large quantities if information. I brought them a package of ham radio periodicals, mostly issues of DL-QTC, the predecessor of cqDL, and got some QSPs (magazine of OEVSV) back. I collect those periodicals to gain and provide access. Seehttp://www.dl4no.de/thema/amateurfunk-zeitschriftenarchiv.htm, catalog at the bottom.

The flea market filled three exhibit halls. If you needed a tube heating for your shack you had a wide choice, from radios to ham equipment to scopes. On the newer side you could get Windows XP packages with the appropriate hardware.

Flea Market Photos Courtesy of Ham Radio Friedrichshafen

A3: Stand mit historischem Radiogeräten

A3: Stand mit Empfängern und Messgeräten (Photo: Ham Radio Friedrichshafen)

A3: Stand mit Empfängern und Messgeräten, hier zwei Schweizer an einer historischen Feld-Telefonzentrale (Photo: Ham Radio Friedrichshafen)

A3: Koffer mit Ham-Radio-Aufklebern aus mehreren Jahrzehnten (Photo: Ham Radio Friedrichshafen)

A3: Alte Radiogeräte (Photo: Ham Radio Friedrichshafen)

A3: Alte Empfänger und Radios (Photo: Ham Radio Friedrichshafen)

A3: Stand mit Empfängern und Messgeräten (Photo: Ham Radio Friedrichshafen)

Yaesu, Icom & Co where there, of course. A large part of Hall 1 had booths for most of the European ham radio societies and other entities. Several attractions for the youths were there: A fox hunt around the hall, possibilities to solder simple circuits and more. The exhibit center even provides a kindergarden.

A1: Hilberling PT 8000A (Photo: Ham Radio Friedrichshafen)

A1: ICOM (Photo: Ham Radio Friedrichshafen)

A1: Wimo, BABY Loop (Photo: Ham Radio Friedrichshafen)

A1: YAESU Funkgeräte (Photo: Ham Radio Friedrichshafen)

Hamradio had lots of presentations. The “SDR Academy” run all over Saturday – completely in English. See http://www.sdra-2016.de. Last year’s presentations are on Youtube. Search for “SDRA-2015”.

My presentation was titled “HAMNET On 70 cm – Possibilities and Limitations”. I should explain that HAMNET is our way to use the 44.0.0.0/8 TCP address space reserved for Ham Radio use. Starting in Germany and especially Austria we use more or less standard WLAN equipment to build a ham radio intranet. User access is mostly on 2.3 GHz and links on 5 GHz. Where we have gaps in the wireless coverage we use Internet wormholes. This way you can access for example packet radio sites in Canada. See http://hamnetdb.net.

2,3 GHz and up means exclusively line-of sight connections. Quite some OMs cannot reach access points this way. The only alternative up to now has been VPN connections through the Internet. I think we could provide relatively fast access on 70 cm. Here in Germany we have two 200-kHz channels for such uses. They were defined in the 1980s for packet radio access up to 76 kbps. This technology is next to dead.

Theoretical calculations show that we could provide up to 1 Mbps and cover up to 50 km if we use modern modulation schemes. You could even improve throughput by making TCP/IP less gossipy. I proposed to use SDR blocks like HackRF or LimeSDR and combine them with a RF frontend (filter, preamp, PA, fast switching). The hardware is more or less readily available, but this is mostly a software topic. While HAMNET relies on standard WLAN equipment with all its limitations for ham radio usage, this system could be completely open. We could it adapt to all our needs and ideas. In the end we could port it back to the microwave bands.

Even if we only work on the lowest protocol levels this will pose quite some challenges. We would need programmers with quite varied expertise from TCP/IP protocols to SDR technology. My presentation was to attract such people. Personally I will not program anything. As a technical writer with a quite wide expertise I might be a bracket for the project and write documentation for it.

A “Peltier Lamp”: The candle heats one side of the Peltier element while the other is cooled by the heat sink. This produces enough electricity to light a LED. (Photo: Alexander DL4NO)

At the opposite end of the exhibit center another fair went on, called Maker Faire. In former times you would have called it “make it yourself”. The exhibits there went from computer modding to 3D printing, knitting and also ham radio. For this I modified my presentation a bit: “WLAN Below 1 GHz – Do You Want To Program For It?” The technology I talked about is near hot topics like Internet of Things or traffic telematics.

Booth of a high school showing the robots they built. (Photo: Alexander DL4NO)

Booth of a high school showing the robots they built. (Photo: Alexander DL4NO)

vy 73
Alexander
DL4NO

Thanks so much for sharing your notes from Friedrichshafen, Alexander. I look forward to attending one year myself! I’m fascinated with the fact that the bulk of the event is indoors–what an incredible venue.

Any other Post readers attend Ham Radio Friedrichshafen? Please comment!

Useful Services for Shortwave DX’ers

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I’m always tinkering, experimenting…trying different antennas and set ups and what not. But, the downside is, I don’t have the patience or a lot of technical skills to hand build stuff, so I have to buy it pre-made.

Like most, I don’t like throwing my money at a crap product. I have found two different folks who make some quality stuff that I wanted to share with the rest of you. I make ABSOLUTELY ZERO $$ from referring anyone to these two folks, but since quality products, good customer service and sometimes, customization are hard to come by, I wanted to share these.

User “lowbander” on eBay makes longwires and dipoles. They come in stock 80 feet lengths with a 9:1 balun and a way to shunt common mode noise to ground. And unlike many longwires/dipoles, lowbanders products come with quality belden coax as well. So you order from him. you’re all set to plug and play

His dipoles and longwires range from $49 to $59, I do believe. Do you need a custom length? Want something shorter or longer then 80 feet? Send him an Ebay message and he’ll take care of you.

Do you need something other then the stock PL259 connector on your cable HE an likely help with that, let him know!

http://ebay.to/28KVp1g

My next find is Craig at K1CRA.COM. It’s mainly a store geared towards ham operators, but he also has a service useful to DX’ers.

He sells RG58 cable for 25 cents a foot, that’s right. 25 cents a foot. It’s the cheapest I’ve found anywhere. For those of us needing cable for our antennas going to our radios, this is a good option. For $8, he can put pl259 connectors on each end. Need something other then PL259’s? Put an order through and add comments on what connections you need and he can do that…I’ve had him do PL259s, 1/8th” (3.5mm) headphone jack types and BNC male connectors on cable for me

https://www.k1cra.com/ProductDetails.asp?ProductCode=DAVISRG58C-U

Select how many feet you want by changing the quantity.. say you want 25 feet? Make the quantity 25. The option to add the connectors is a bit down the page, with a checkbox.

Both lowbander on eBay and Craig at K1CRA ship via USPS priority mail. I had lowbander send me a package from Kansas City on a Friday and I had it here in Alaska on a Tuesday!

I have probably close to $500 worth of Lowbanders antennas and Around $150 worth of product from K1CRA.com stuff

I live in an area far from most of anything now, so finding good quality products at an affordable price from people you can trust is hard, and I just wanted to share these two.

Paul Walker is located in Galena, Alaska and is a regular contributor to the SWLing Post. Be sure to check out Paul’s YouTube channel and SoundCloud channel where everything he logs is recorded and posted. Click here to read his other contributions on the SWLing Post.

Shortwave Logs from Alaska’s Central Interior Region

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Here are some Shortwave logs from the central interior region of Alaska. I used a Tecsun PL880 and 225 foot long wire with Emtech ZM2 Tuner or a Wellbrook ALA1530LNP.

I’ve only used the Wellbrook for two days so I can’t really offer a thorough comparison yet. There was one case in particular where the 225 foot long wire and ZM2 tuner beat the Wellbrook by a large margin.

I don’t log everything I hear, but everything I do log gets recorded into an mp3 format audio clip. The audio recording helps tremendously with my QSL return rate, especially when I am hearing a broadcast in a language I don’t understand

I hear China Radio International, China National Radio, Radio Nacional de Brasilia/Amazonia, FEBC, World Harvest Radio and others regularly so I don’t log them because I try and keep my logs to what is interesting for one reason or another (programming, music, etc.) or rare/interesting.

3260 & 3325 kHz Papua New Guinea, NBC Radio. 1027 to 1034 UTC. 3325 Bouganville is carrying a man talking in a combination of Pidgin and English discussing mines, mine safety and mine regulations. Better then average signal with only light fading and interference. 3260 kHz Mandang is running music followed by an announcer talking about what I think are upcoming programming highlights. Fair signal, way better then usual

NBC Radio Mandang 3260 kHz audio: https://goo.gl/pmB8DD

NBC Radio Bouganviulle 3325 kHz audio: https://goo.gl/WKKEPJ

4870 kHz Indonesia, Radio Republik Indonesia Wamena. June 12 1001 UTCA regular visitor in the early morning hours here. not daily, but here often. Today’s signal is fair but with a moderate amount of fading and static crashes/interference. Usual fair of what I think is local music is being played.

Radio Republik Indonesia Wamena 4870 kHz audio: https://goo.gl/hjF1JL

5020 kHz Solomon Islands, Solomon Islands Broadcasting Corporation. June 12 1011UTC. Higher side of good signal with all factors taken into account. Only a little bit of fading during christian music.

Audio of Solomon Islands Broadcasting Corporation 5020 kHz here: https://goo.gl/d8BFX2

5745 kHz US, VOA Radio Gram. June 11 0943. The first time I logged VOA’s Radio Gram broadcast. There was something creating a loud buzzing noise but I could still hear the digital data. Only a little Russian text and text in english decoded for me. I will definitely try again!

VOA Radio Gram 5745 kHz audio here: https://goo.gl/LfxJ6w

6070 kHz DPRK, Voice of Korea.June 11 1005UTC. Fair signal, but low modulation. Announcers voice is lower then the music. Fair amount of fading. I heard their usual marching/patriotic music. This is not a frequency I usually hear them on, wether owing to I am not out when this frequency is on, conditions or I hear usually CFRX Toronto.

Voice Of Korea 6070 kHz audio here: https://goo.gl/SzXuEg

6115 kHz China, Voice of Strait. June 11 1008 UTC. Fair signal with a fair amount of fading. Sounds like a man talking, could be a news broadcast or interview. Not sure.

Voice Of Strait 6115 kHz audio here: https://goo.gl/V92tlD

7260 kHz Vanuatu, Radio Vanuatu. June 7 0857UTC. Low side of fair signal with interview in english and mentions of Vanuatu. Interview ends and music plays, one song sounds like it’s a kids chorus. There is a fair amount of fading and static crashing/atmospheric noise. Radio Vanuatu is habitually, chronically, woefully unde rmodulated on a daily basis. Just a few days after this logging was made, I had what my radio signal meter showed as a good signal but NO audio. The signal was so under modulated I had no audio but I had a signal! I would actually listen to them if they played more music and had better modulation

Radio Vanuatu 7260 kHz audio here: https://goo.gl/V1GMQS

9545 Solomon Islands, Solomon Islands Broadcasting Corporation. June 11 0835. SIBC was on over 3 hours late on 9545 kHz, it’s supposed to sign off at 0500UTC and switch to 5020 kHz but at 0835UTC this night it was still on. 9545 kHz staying on late has been happening a lot lately. 9545 kHz is used as SIBC’s workday frequency with 5020 kHz being used in the early to mid morning and afternoon/evening. In this recording SIBC is fairly strong here with light fading and static. Whenever 9545 kHz is on late, it seems to be stronger then 5020 kHz would be. My logging tonight starts with an interview then music is being played.

Audio of SIBC 9545 kHz here: https://goo.gl/0AIj5n

12035 Mongolia, Voice of Mongolia. June 11 1018UTC. NEW! This is a new logging for me. weak signal playing music. Was able to match the interval tune and the announcers voice heard during my logging with a clip of a recent broadcast on their website.

Audio of Voice of Mongolia 12035 kHz here: https://goo.gl/Y2QXH7

15400 kHz Romania, Radio Romania International. June 12 1006 UTC. News broadcast in French. Somewhat weak, but steady signal with only light fading.

Audio of Radio Romania International 1540 kHz here: https://goo.gl/OBK0Q9

17770 kHz Phillipines, Radio Liberty targeting Siberia. June 12 0948. What sounded like a man in Russian during a news broadcast or interview. Weak but steady signal.

Audio of Radio Liberty 1770khz here: https://goo.gl/5fxzxJ

I could use some opinions and inputs from others on something:

I am DXing about 500 feet from the transmitter sites for KXES-LPFM 92.9 and KIYU-FM 88.1 along with K10LJ Channel 10. The FM’s are only 100 watts and the TV station is only 10 watts of Digital RF. However, the FM’s overload my Shortwave radio around 9.4 to 9.6 MHz along with the lower to mid part of the tropical bands. I have a MCM Electronics and Radio Shack FM trap and they help a bit, but don’t do nearly enough. I am willing to spend $100 or so for a good FM Trap/Filter. I’ll spend a little more if I have to and the product is proven at works. I can null out the interference by rotating my Wellbrook ALA1530LNP, but I may be nulling out the signal I want to hear at the same time. Returning things for me is a hassle so I’d rather pay good $ for something that works. Feel free to email me, [email protected] or reply to this thread.

Guest Post: My Evolving, Morphing, SW Listening Station

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Many thanks to SWLing Post contributor, TomL, for the following guest post:

My Evolving, Morphing, SW Listening Station

by TomL, May 26, 2016

My interest in radio listening has been rekindled after a long hiatus in parallel to my dwindling interest in Mainstream Media. It is now about 8 years without cable TV and I seriously do not miss it, especially with the evolving nature of discovery with respect to other forms of media. SWL radio was important to me in my formative years during the Cold War; fascinating were the many ways governments used shortwave radio to influence populations, each with their own brand of propaganda! Young people today know nothing about the endless (and entertaining) tirades of East German editorial commentaries denouncing the evil, decadent West. Or, of the free, large-sized envelopes full of travel and promotional brochures, pennants, bumper stickers, and booklets sent from the government broadcasters such as Poland, Hungary (yes, communist countries!), Australia, Netherlands, etc. just for sending in one simple QSL report!!!

I quickly realized that those days are gone forever, consigned to a period of history where radio was THE main method of disseminating copious amounts of government propaganda to very large swaths of humanity. Now, the internet and cable TV fulfill that function in a much more CONTROLLED manner, both technically and socially (Big Brother like). So, I have diversified my interests and have an unusual listening station. It is multiple things in one small space. You see, I live in a very small condo in a noise-plagued environment with only a 2nd floor wooden deck (owned by the Condo Association!) in which to put up any outside antennas. Only a single “Dish” type antenna is allowed. So my shortwave antenna needs to be well hidden. Same for the TV antenna, since I also have a north-facing deck, I cannot have any line-of-sight to the Southern sky for a Dish.

The first wire antenna strung from the top and brought inside was a dismal failure receiving nothing but noise. I gave up for a couple of years. I built a loop TV antenna and mounted an FM antenna instead since those were less susceptible to noise issues. Also recently added to this station are two cheap 4G antennas with wires into a single Verizon USB aircard plugged into my computer and getting up to 14 mbps performance.

But, I still wanted to try shortwave radio again (and medium wave too) but the noise issues were very, very discouraging. S9 noise on some bands. Tried preselector, a noise “phaser”, different lengths. Nothing worked. However, I read something from an amateur radio operator in Northern California who had a space problem. He put up a helically-wound-vertical (HWV) antenna with radials for 160 meters (John Miller HWV antenna). I also read about various “broomstick” antennas. So, I tried my own version with an old RF Systems Magnetic Longwire Balun I still owned and NO radials. Put it together with a 2 foot long, 4 inch schedule 40 PVC pipe wrapped in 200 feet of 18 awg magnet wire. Well, still noisy but, at least now I had a portable antenna!

So, I went camping in March of this year! Holy Cow, was it cold out but the helical antenna performed well enough to hear All India Radio for my very first time, a small 1kw Mexican station in the 49 meter band, and various others from Asia that were elusive for me in the distant past. I was finally encouraged again to continue my research. I did this a few more times and finally got tired of going camping just to listen to a radio! NOISE at home was still the big bugaboo to kill (and it still is).

I read up on Common-mode noise travelling on ground and shield components of antenna systems. So I bought a bunch of toroid ferrites of different types to cover different frequencies (something about initial permeability….) to make my own homemade “Super RF Choke” to cover all frequencies made on a Home Depot Homer bucket lid, winding the coax 5 or 6 times through all the toroids, the full diameter of the lid.

Measurements by Jim Brown published on the web (RFI-Ham.pdf), pages 32-33) indicate good choke performance using coax with these larger-sized coils. I still hoped to salvage the use of the HWV antenna. So, added the choke and noticed some improvement across most bands (less noise). Medium wave broadcast was not effective and decided that I did not want to keep tuning an antenna that HAD to sit outside to get away from the noise inside my listening station.

I also shut off the power to my condo and found out which noise sources were mine vs. other noise that came from all the neighbors (very important step to do!!!). For instance, I did not know before that USB charging adapters are PURE RF-NOISE EVIL in an innocently small package?!?!?! I rearranged wiring to shut off certain devices and power strips when I want to listen to the radio!

So, I kept reading. Found out about another magnetic balun from Palomar. Tried it but not impressed – performance was too lossy compared to the good old RF Systems MLB (what a great product that was back then!). Kept reading and found out good things about the EF-SWL from PAR electronics (product is now made and sold by LNR). The ground connections on it (and the Palomar) intrigued me. So, I decided to go to Hamvention for the first time, even though I was skeptical of finding anything useful, I told myself, I could at least buy the EF-SWL on sale (which I did).

Installed EF-SWL to the HWV but no difference compared to the RF MLB. The antenna did perform better outside on the deck in the far corner, so there it still sits. Then, I hooked up the wire they gave me with the EF-SWL to the ground and it resulted in MORE noise. Then, took off the jumper (which connects the coax shield to the ground side of the balun) and connected only the middle post (balun ground) to the ground wire and a lot LESS noise resulted along with a small reduction in radio signal level!!! Finally some progress – the wire seems to be acting like an old-fashioned “counterpoise”, which is misunderstood these days. Apparently, back in the 1930’s-1950’s, people involved in radio knew the differences between an “earth ground”, a “radial system”, and a “counterpoise”. Technically, they are all different and their use is different as a result. Now, people moosh all these concepts together interchangeably which risks creating very ineffective antennas.

Photo of installed EF-SWL at the bottom of the HWV with coax at the output, the red magnet wire input on top, the middle post for the counterpoise wire, and the coax shield post is unused.

The HWV antenna now has 600 feet of 26 awg teflon wire on the outside PVC, an inside 3 inch PVC “sleeve” with 102 Russian ferrite rods, a 56 inch stainless steel whip at the top, and one inch hole through the center to accommodate the 7 foot PVC mount to my carbon fiber photo tripod when I take it camping again.

So, I am on a new quest to understand counterpoises, how to actually TUNE them and, hopefully, how to use them to increase the performance of shortened antennas like my HWV (something about reducing the dB loss incurred by shortening….). A second result I hope will be how to use the counterpoise to keep signal-to-noise ratio high at the same time (maybe with this used $100 Dentron Super Tuner bought at Hamvention?).

Also bought at Hamvention (thanks Thomas W. for the tip!!) and installed Bonito’s Galvanic Antenna Isolator GI300.

If input directly to the input of the radio, led to more reduction in noise and signal!! Too much actually, so I took off my Super RF Choke and now I had a better result compared to the EF-SWL with the RF Choke (slightly cleaner sound with less hissy noise). Apparently, the GI300 completely isolates the coax shield, better than my homemade choke! The requirement is to use coax from the feedpoint and not bare wire. I then placed a few clamp-on ferrites I bought from eBay to help with slightly higher frequency choking of the shield at various places on the feedline.

Photo of GI300 on radio with NO extra coax lead into the radio at right (Thanks to Dennis Walter of Bonito for that tip)

Before Hamvention, I wanted to try out AM broadcast. I wanted to know more about this “FSL” antenna a well-known eccentric from Ireland (Graham Maynard FSL) developed before he passed away a few years later. So read up and bought a whole bunch of ferrite rods and tried different configurations. Well, my particular design did not work all that well because I did not follow directions for winding wire into a balanced design. So, I added all those ferrite rods to the 2 foot HWV (inside a 3 inch thin-walled sewer PVC pipe). The antenna is louder down to about 3 MHz with a stronger signal (including noise) than without. I do not have measurements, and find it too time consuming to document. Maybe one day, I will compare and document by sliding the ferrites out on the 3 inch PVC and measure actual signal levels. The ferrite sleeve seemed to pick up MORE noise and radio signal than without it. So, if you need more signal strength in a small package below 7 MHz, then the idea seems to have merit. But since it increased noise as much as radio signals, it has limited usefulness to me. I do have another project where I will put ferrite bars onto a tuned medium wave loop antenna (Tecsun AN100) that is much more portable and directional. The bars and loop were both relatively inexpensive from eBay. The ferrites change the tuning lower, so I have to figure out how to make it tune higher again…….

Photo of unfinished MW loop project.

Summary

Evolving understanding of dealing with major problems like overwhelming noise and limited space have led to unexpected additions to my SW Listening Station:

A 2 foot long, 4 inch diameter helically-wound-vertical antenna (HWV) with way too much wire on it (and now inserted with 102 160mm Russian ferrite rods on a 3 inch diameter “sleeve”). Originally built because of its portability. Can now be mounted on a carbon fiber photo tripod with a 7 foot 3/4” PVC pipe through the center length
A magnetic balun from LNR (designed by Parfitt) attached at the feedpoint of the antenna
A proprietary galvanic isolator from Bonito attached right at the radio’s antenna terminal
A “boat anchor” Dentron Super Tuner attached to the HWV feedline to help tune it
An unfinished MW loop antenna with more ferrite bars
An unused, homemade toroidal Super RF Choke
Clamp-on ferrites everywhere in proximity on wires and power leads
Re-arranged power strips and wires as needed for easier shutoff in functional groups

For shortwave, I still pick up mostly noise on many bands. With the uncalibrated S-meter on the ICF-2010 – 49 meters is around S1 (before about S3). 31 meters is MUCH improved and is now listenable to stronger stations (S2 instead of S7 noise!). Even 19 and 16 meters is improved from S6 to S7 down to about S3 now – noise still too annoyingly loud to understand any language being spoken however. And forget about DXing from this location! Will have to go camping again soon.

BUT, listening now to Voice of Greece, Radio Nacional Brasilia, or Radio Romania International is a much cleaner sounding experience than just a couple of months ago. They are there to re-discover and appreciate, even though many speak a foreign language and I do not understand a word they are saying! Also, there is the odd observation (like just this morning), that I can actually learn to enjoy listening to Country Music if it is the unique sounding Australian flavor!!

Do I miss cable TV?? Not a bit!!

Future investigations

Employ the Dentron Super Tuner in various configurations to find any improvements (currently attached to the coax of main feedline from the EF-SWL, it is helping tune different SW bands (not sure why it helps, does not make sense, must be a mismatch between coax and balun)
Obtain old book(s) on counterpoises
Get a Linear DC power supply for use with all the EVIL RF-spewing devices that use 5 volts. Maybe this one: (Tekpower 3Amp Linear)
Replace any cheap/old RG58 cables with LMR-240 or similar
Finish the AM loop w/ferrites so I can take it places
Perhaps an ultra low-noise outdoor amplifier for the HWV, depends on counterpoise experiments: (Wellbrook ALA100M-2) (I don’t want to spend that much money now)
Somehow use a noise antenna with a better phaser: (DX Engineering NCC-1) (gulp, don’t want to spend THAT much money now also!!!)
Get some relief from background noise using a really robust noise blanker. I don’t want to spend on the portable radio, would rather get something like the Bonito 1102S or an ELAD model both supposed to have excellent audio quality and excellent DSP noise blankers. But that means getting a cheap laptop to run it and replacing the Sony. MOAR big bucks…. but not right now
Maybe a real loop antenna, BUT it has to be remotely tunable and remotely turnable and small enough to HIDE. MOAR big bucks, sigh….

TomL from noisy Illinois, USA

Many thanks for sharing your experiences, Tom! Also, it was great meeting you at the Hamvention this year.

I must say that there is something to be said for brute-force experimentation when it comes to mitigating radio interference. I hope you keep us posted as you continue to experiment and improve upon your unique listening system.

Solomon Islands and Vanuatu On Shortwave

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Paul Walker’s listening post in Galena, Alaska.

by Paul Walker

I tried logging the Solomon Islands and Vanuatu shortwave broadcast stations for years, however, owing to my location and poor antenna along with technical problems with the stations, I was never able to log them.

Well, I recently moved to Alaska and was able to take the stations off my “Most Wanted List.”

SIBC has two frequencies–5020 kHz and 9545 kHz–both with 10,000 watts. They use 9545 kHz during their local workday time frame and the 5020 kHz frequency is their late night and early morning frequency.

A few times, I have caught 9545 kHz not signing off at 0500UTC for the switchover to 5020 kHz like it should of. When 9545 kHz is on late, the signal is usually pretty darn good.

In fact, on April 25th, I caught 9545 kHz on about 2 1/2 hours past the scheduled switchover and the signal was AMAZING! It was near perfect with a rock solid signal, fading so slightly it’s barely noticeable, no interference and pretty good audio!!

For whatever reason, when 9545 kHz is on late, It seems to have a better signal most times then 5020 kHz would if it was on at that time. SIBC has one transmitter so two frequencies can’t be on at once. Both times I’ve caught 9545 on late, it signs off abruptly and minutes later, 5020 kHz is on, as it should be.

As for 5020 kHz, this recording on May 22 at 1148 UTC this was about the best I’ve ever heard it.

Listen closely when SIBC goes to dead air before shutting off the transmitter, I clearly hear two people talking.

As for Radio Vanuatu, their signals seem to be chronically/habitually under modulated and combine that with the large amount of speech programming they ran…and they are hard to catch. Good luck hearing them on 3945 kHz. Even with Radio Nikkei off, the best I’ve ever gotten from 3945 kHz was a signal so poor all I could make out was the speech on 3945 kHz and 7260 kHz matched.

On May 14th at 0923 UTC, I got about the best signal out of Radio Vanuatu on 7260 that I’ve ever had. Conditions must have been good and that combined with the fact they were running music made them a bit easier to hear.

For those that don’t know me, I am living in Galena, Alaska a village of 500 people in rural central Alaska, halfway between Nome & Fairbanks. I work here as the Program Director for a small network of community radio signals along the Yukon river. I DX from the river bank 500 feet from my apartment with a Tecsun PL-880 and 80 foot or 225 foot long wire, soon to be a Wellbrook ALA1530LNP.

Guest Post: Communications Service Monitors – A Radio Hobbyist’s Perspective

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Many thanks to SWLing Post contributor, Mario Filippi (N2HUN) for the following guest post:

Communications Service Monitors – A Radio Hobbyist’s Perspective

Mario Filippi, N2HUN

(All photos courtesy of author)

Over the past few decades I lusted after a communications service monitor for my radio hobby but prices were always prohibitive; several thousands of dollars for a new model and tens of thousands for high-end ones. Not being a working professional in the communications field made it difficult to justify purchasing a piece of equipment whose price tag rivaled a down payment on a house. So, fast forward a few decades later and now life and times have fortunately changed for the better; the house is paid for, the job is secure, the income is finally steady, life is good financially, and to boot many of these older service monitors manufactured by Ramsey, Motorola, Wavetek, IFR/Aerotek, Cushman etc., are currently being sold on the pre-owned market at a fraction of their original decades-ago hefty prices. These service monitors are finally in financial reach of electronics hobbyists who will find many uses for these former electronic workhorses that toiled many years in the industry and now, in their golden years are being retired and becoming available for a second life via reuse/reincarnation/repurposing/reinvention.

Work of Art: Author’s Ramsey COM3 Service Monitor

So what exactly is a communications service monitor, or “service monitor” as the folks in the trade refer to? Well it is an instrument for servicing AM and FM radio equipment, although some units also have the ability to service SSB equipment. The service monitor is basically a highly accurate and precise receiver and low-power signal generator all in one allowing a technician (or electronics hobbyist) to perform service, repair, or alignment of radio equipment. Most of us have had the experience of owning a malfunctioning radio whether it is an AM or FM broadcast radio, two-way radio such as a CB (Citizen’s Band) radio, pager, or a ham radio transceiver, and that is where a service monitor proves its value and utility because now you, the hobbyist, can perform the work yourself.

My Friend’s Ramsey COM3010 Service Monitor, Big Brother of the COM3

As a radio enthusiast (shortwave, ham radio, satellite communications) for over half a century, I’ve definitely owned more radios than shoes; everything from AM, FM, shortwave receivers to CB radios to ham transceivers, all in different stages of health and vintage. For years I relied on standalone RF signal generators, audio generators, frequency counters, and CTCSS decoders to aid in rehabbing, troubleshooting, and aligning each of the many units that paraded past my radio shack. Then one day a friend showed me his service monitor, the Ramsey COM3010, another venerable workhorse still in production, and it was a defining moment; the time had come to invest in one.

Aligning a Uniden President Washington CB Radio Prior to Owning a Service Monitor

My Ramsey COM3, purchased second-hand from an Internet auction site for $400.00 is a no frills, basic unit without the features found in more sophisticated service monitors having built-in oscilloscopes, spectrum analyzers, frequency sweeping ability, and frequency scanning ability. The COM3 was in production from the late 1980’s to around 2003 at a price of around $2500 (ca. 1989) and was considered a workhorse in its time, weighed 13 pounds with the internal battery, and was easily luggable from site to site. It covers from 100 KHz to 999.999 MHz and has become an invaluable tool in my radio shack for measuring a transmitter’s operating frequency and deviation, measuring receiver sensitivity, S meter calibration, and checking CTCSS tones on my two way VHF/UHF radios. My unit evidently had an easy former life as the only needs were to replace the internal battery, perform an external cleaning, check transmitter and receiver accuracy and check accuracy of the internal audio generator. Interestingly, Ramsey Electronics (www.ramseytest.com) still services and calibrates COM3s.

Vintage Tempo One Transceiver Restoration Was Made Easier with the COM3 on the Bench

So, if you’ve been dreaming of owning your own communications service monitor either as a hobbyist or small repair radio shop proprietor then start looking as there are plenty of used units out there; you’ll pay top dollar when buying from a commercial vendor but at least you’ll get some form of warranty. If instead you travel the same road I did, via an Internet auction site, there’s lots more risk involved, but the plus is you’ll save big if you do your homework by checking past auctions, seller feedback scores, and determining what price the market is bearing by looking at the winning bids. In closing, the COM3 owner’s manual is available on line by doing a simple search, and a review of the Ramsey COM3 by Larry Antonuk which appeared in the August 1989 issue of 73 Amateur Radio Magazine is also available as a free download.

Mario, thank you for another brilliant guest post! I always learn something new from your articles. By the way: I have that same Nye Viking straight key–it obviously pairs beautifully with the Tempo One!