Tag Archives: Guest Posts

Guest Post: An Introduction to DXing the MF Marine Bands

Many thanks to SWLing Post contributor, Don Moore–author of Following Ghosts in Northern Peru–for the following guest post:

Monitoring the MF Marine Bands

By Don Moore

For me, DXing has always been about the challenge of receiving difficult-to-hear radio stations, regardless of the type of station or frequency range. In my five decades in the radio hobby I’ve logged a lot of different kinds of stations – shortwave broadcast, medium wave, shortwave utility, longwave beacons, etc. But some of my favorite catches have been in the upper end of the medium frequency range.

Technically speaking, medium frequency (MF) is the range from 300 to 3000 kHz and includes the standard medium wave (AM) broadcast band. The upper end of the MF band, from 1600 to 3000 kHz (except for a small portion reserved for amateur radio), has always been assigned to various types of utility uses including broadcasts and other voice communications from regional maritime stations. And while digital modes and satellites have done a lot to change the nature of communication with ships at sea, there is still a lot of good human-voice DX to be heard.

Several dozen stations, mostly in Europe and North America, broadcast regularly scheduled marine information broadcasts in the MF range. These broadcasts are usually between five to ten minutes in length and include weather forecasts, navigational warnings, and other notices to keep ships at sea safe. On occasion it’s possible to hear two-way voice communication here between ships and shore stations, although that’s much less common today.

The Equipment

Nothing special is needed to DX the marine MF band other than a receiver that covers the frequency range and can receive USB mode (which all these broadcasts are in). However, for reasons explained below, I highly recommend using an SDR to make spectrum recordings of the entire band to go through later. Continue reading →

Airspy HF+ Discovery & Shortwave Portables: Having Fun with the Airspy YouLoop!

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Many thanks to SWLing Post contributor, Bill Hemphill, who shares the following guest post:

YouLoop Antenna Fun

by Billy Hemphill WD9EQD

Like many listeners, I live in an antenna restricted community. While I have strung up some hidden outdoor wire antennas, I have found that they didn’t really perform that much better than just using the telescoping antenna with maybe a length of wire attached. The biggest problem (whether indoor or outdoor antenna) has been the high noise floor.

A few months ago I bought an AirSpy HF+ Discovery SDR receiver. I had already owned a couple of SDRPlay SDR receivers, but the high noise floor limited their performance. I had read good reviews about the AirSpy, especially its performance on the AM Broadcast band and the lower shortwave bands.

I have about 80 feet of speaker wire strung from the second floor and across the high windows in the living room. This does perform fairly well, but the high noise floor still exists.

A couple of weeks ago, I bought the YouLoop Magnetic Loop antenna from AirSpy. I gave it a try and am amazed at the lower noise floor compared to the indoor wire antenna.

Wire Antenna vs. YouLoop–some examples:

AirSpy with Wire Antenna

AirSpy with YouLoop

AirSpy with Wire Antenna

AirSpy with YouLoop

AirSpy with Wire Antenna

AirSpy with YouLoop

Dramatic reduction in the noise floor. I’ve done a lot of playing around with it and find that the YouLoop picks up just about the same stations as the indoor wire antenna does. But with the lower noise level, the YouLoop makes it more enjoyable to listen. Overall, the YouLoop is now my main antenna.

YouLoop with a Portable Radio

It works so well with the AirSpy, I started wondering if I could use it with a portable radio, like the Tecsun PL-880. But the AirSpy website has the following note:

Note: It is very likely your third party radio will not be sensitive enough to operate with the YouLoop properly. We have even seen self-documented failed attempts to build pre-amplifiers to compensate for the lack of sensitivity and/or the required dynamic range in third party radios. Use your brain, and eventually an Airspy HF+ Discovery.

Doesn’t sound like it will work with portable radios. BUT, I’m always one to try anyway.

Tecsun PL-880

Since the YouLoop has a SMA connector, I bought a SMA to 1/8” phone jack cable. Plugged it into the PL-880 antenna jack and found I had almost a dead radio. Very few stations heard. But in playing around, I accidentally touched the phone plug to the telescoping antenna and instantly got strong signals.

I did some very unscientific tests. I attached the YouLoop through the side antenna jack, did an ATS scan, then did the same with the YouLoop clipped to the telescoping antenna. Also did a scan with just the telescoping antenna fully extended.. I got some very interesting results. These were done one after the other, so there can be differences in signal fading, etc.

I have repeated the above test several times at different hours. While the actual number of ATS stations varied, the ratio between them remained fairly consistent to the above numbers.

From the above, it appears that the telescoping antenna circuit is more sensitive than the 1/8” antenna jack circuit. Maybe some attenuation is being added to the 1/8” jack since it’s more likely a higher gain antenna would be used there. Can anyone confirm that the circuit indeed attenuates thru the antenna jack?

The YouLoop seems to be a decent performer when directly clipped to the telescoping antenna. While not as good as a high gain outdoor antenna would be, it definitely is usable for indoor uses.

I also tested it clipped to the antennas of some other portable receivers. Tecsun S-8800, PL-330, Panasonic RF-2200 and Philco T-9 Trans-World receivers. All showed an increase over just using the telescoping antenna.

Some interesting notes:

The Tecsun PL-330 saw the same reduction in signal when directly plugged into the antenna jack as opposed to clipping on the telescoping antenna.

The Tecsun S-8800 did not show that much of a drop. I basically got the same number of stations when clipped to antenna as when I connected to the BNC jack:

In conclusion, I find that I can use the YouLoop with my portable radios to increase the signals on strong stations when used indoors. And it is quite the performer when used with the AirSpy HF+ Discovery SDR receiver. It easily portable and I find that I move it around the house as I need to. I just hang it off a window curtain rod. I may just order a second one so that my family room radio has one permanently attached to it.

Click here to check out the Youloop at Airspy.com.

Guest Post: Pavel’s Homebrew “Monster” Drain Pipe FSL Antenna

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

Building a Drain Pipe FSL Antenna

by Pavel Kraus

Hi, I greet all DX fans and the entire SWLing Post community! I enjoy reading reading this blog and the diversity of contributions from our authors and contributors; many thanks from me for so much useful information.

The following are the construction notes of my FSL antenna, which I designed thanks to the suggestions of GaryDeBock, and other FSL designers.

The antenna is a classic design featuring 60 ferrite rods 200x 10 mm, which are placed on a plastic sewage pipe.

Pict 3: Pipe with ferrite rods and windings

Pict 4: Pipe with ferrite rods and windings

In addition, sewer pipe sections are used for the entire antenna cover. I assume that this material can be obtained in other countries as well. Continue reading →

AGA Nostalgia Trip: Haluk soon to be reunited with his childhood radio

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Many thanks to SWLing Post contributor, Haluk Mesci, who shares the following guest post:

AGA is the agha of radios…

by Haluk Mesci

Full disclosure: Contains nostalgia of ‘my parent’s radio’ and some 36 ‘and’s…

I was born and raised in Turkey. Throughout some part of my primary and secondary school years–between 1960 to 1968–we enjoyed listening to an AGA tube radio in the family room.

Although AGA is mainly Swedish as far as I know, I re-discovered a stock photo of it on agamuseum.nl which is Dutch:

Ours had a ‘magic eye’ just above the tuning knob on the right

I remember, at age 9, trying to listen to a live broadcast of a soccer match between Fenerbahce–my favorite team–and the French team of Nice: There was a ‘Nis’ -Turkish spelling- on the MW screen, so there had to be a broadcast, right? Wrong.

I learned much later that it wasn’t that easy on radio. (Alas, my team was devastated 5-1 anyhow.) Similar ‘search’ for ‘Russian Sputnik sending messages to the world’ yielded nothing but strange sounds like ‘a diesel engine working loudly’… I wasn’t a silly kid, but nobody taught us basic radio then.

Years passed and my family relocated to Samsun, another city by the Black Sea, because of my father’s work. I was about to graduate from ODTU and there was the famous leftist (anti-US etc) ‘boycott’s of 1968 and later, I had to go live with my parents while my university courses remained suspended.

Ironically, the city had a US radar base; the base had a low power MW radio station broadcasting news and music -rock and country etc- 24 hours in English to the base staff: AFRTS 1590 kHz.

Shortly thereafter, the base was closed and the radio station went off the air, maybe because of the boycotts and the political winds in Turkey, so I had to look up another such station. Continue reading →

Jock explores “The Essential Listening Post”

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Many thanks to SWLing Post contributor, Jock Elliott, who shares the following guest post:

The Essential Listening Post

By Jock Elliott, KB2GOM

Listening to shortwave radio (or any radio, for that matter) is just plain fun.

So what do you need to get in on the fun?

A radio. With today’s crop of portable SW radios, many of which have search and store capabilities, a newbie SWL can get started quickly without a lot fuss and bother and no extra stuff. Just hit the search and store function (it has different names on different radios), let the search function do its thing, and step through the memories to see what’s out there. If your radio doesn’t have search and store, you can just tune around to see what’s currently broadcasting or, if you have a computer or smart phone, use it to explore one of the online directories like https://shortwaveschedule.com/

What follow next are some things that I’ve found increase my enjoyment of SWLing. Continue reading →

Radio Mods: Unblocking the YAESU FRG-8800 Frequency Coverage Limitations

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Many thanks to SWLing Post contributor, Paolo Viappiani (SWL I1-11437), who shares the following guest post. Note that, as with any radio modification, perform this operation at your own risk. This is a very simple mod, but if you feel it might be beyond your skill level, consider hiring a radio technician to perform it on your behalf:

Unblocking the YAESU FRG-8800 Frequency Coverage Limitations

by Paolo Viappiani

Figure I: An unblocked FRG-8800 receiver tuned to 29.999.9 MHz.

Introduction

It is well known that some receivers produced in the last decades of the last century suffered from a limited frequency coverage due to legislative restrictions in force in some countries (Germany, Australia, etc.).

In particular, in Germany it was forbidden to listen to HF frequencies higher than 26.1 MHz, while in other Countries shortwave were not allowed to receive frequencies below 2 MHz.
These restrictions led most radio manufacturers to produce “blocked” versions of their HF receivers in order to satisfy the various national requirements; almost classical examples are the world renowned SONY ICF-2001D and the PHILIPS D-2935/D-2999 portables.

The blocking/unblocking procedure of some frequency bands was quite simple in microprocessor-governed synthesized radios: usually it was sufficient to add (or remove) proper jumpers in the vicinity of the microprocessor to perform the task, and the correct procedure was often covered in the Service Manuals or in specific Technical Bulletins; in any case plenty of information can be found on the Internet. Continue reading →

Dan reviews the CountyComm GP7/SSB (Gen 4)

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Many thanks to SWLing Post contributor, Dan Robinson, for the following guest post and review:

CountyComm GP7 / Tecsun PL-368: Is It All You Need?

by Dan Robinson

It’s been a long wait, but CountyComm, that supplier of all kinds of neat and useful stuff, finally released the GP7 SSB (Gen 4).

As the name states this is the 4th generation of the series of radios adapted by the company from the Tecsun PL-36xxx series of receivers (there was at one point a GP6 that was a never-released special project).

All photos by CountyComm

This walkie-talkie style, though receive-only, portable has undoubtedly been a big seller for CountyComm since the first model came out. It’s popular not only with SWLs and amateur operators but also with preppers.

When OEM Tecsun finally did what everyone was clamoring for – redesign the radio with a keypad and including features associated with the PL-880/330/990x/501x receivers – the ground shook. Continue reading →