Tag Archives: Longwave

Grimeton Radio / SAQ LF transmitter on the air May 1, 2018

Alexanderson alternator in the SAQ Grimeton VLF transmitter.

(Source: ARRL via Mike Hansgen)

Low-frequency World Heritage Grimeton Radio Station, SAQ, will transmit from Sweden on May 1 as participation in the European Route of Industrial Heritage’s “Work It Out” observance.

“As part of the event, we plan for the first SAQ transmission since 2016,” said Lars Kalland, SM6NM. The transmitter start-up will begin at 0930 UTC, with the transmission to follow on 17.2 kHz CW at 1000 UTC.

A live video stream of the event will be available. Kalland said no QSL cards will sent, nor will SAQ post a list of reports, but SAQ does invite brief listener reports via e-mail.

“We sincerely hope that all the SAQ transmission on 17.2 kHz will go as planned,” Kalland said. “But, as always, there is a reservation that the transmission [may be] cancelled on short notice.”

Click here to read on the ARRL website.

Indian Standard Time via new longwave site

"India (orthographic projection)" by Ssolbergj (talk) - Own work,This vector image was created with Inkscape.Aquarius.geomar.deThe map has been created with the Generic Mapping Tools: http://gmt.soest.hawaii.edu/ using one or more of these public domain datasets for the relief:ETOPO2 (topography/bathymetry): http://www.ngdc.noaa.gov/mgg/global/global.htmlGLOBE (topography): http://www.ngdc.noaa.gov/mgg/topo/gltiles.htmlSRTM (topography): http://www2.jpl.nasa.gov/srtm/English | italiano | ?????????? | ??? | +/?Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.. Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:India_(orthographic_projection).svg#mediaviewer/File:India_(orthographic_projection).svg

(Source: Southgate ARC)

India to employ long wave radio technology

Two towers, about three times the height of the Qutab Minar, are likely to be erected at as-yet-undecided locations in the country for disseminating Indian Standard Time.

The National Physical Laboratory, an organisation charged with ensuring that Indian time stays accurate, has signed an agreement with IFR Information Dissemination Services (IFR) Ltd., which will set up the towers and employ long wave radio (LWR) technology to purvey this time to a range of users, from phone companies to railway stations. Customers will need a microchip that can be embedded into everything, from wall-clocks to servers.

“Long range radiowaves from the towers can be reliably transmitted even during major disasters. Other than time, information such as a tsunami warning or weather warnings can also be sent,” Pawan Kumar Kasera, director, IFR, said at a press conference. IFR is affiliated to the Germany-based EFR GmbH, which is in the business of providing similar services in Germany.

The company now requires a plethora of permissions from other government departments to host these towers, each with a range of 1,000 km, and an investment of about Rs. 600 crore, which it will raise privately.

The NPL would help IFR keep their caesium clocks (located in the tower) calibrated but wouldn’t be involved in setting up the infrastructure related to time dissemination. Last year, the Council of Scientific and Industrial Research-body had tied up with the Indian Space Research Organisation to provide time-related services for its satellites. “The advantage of LWR is that the waves travel close to the ground and so can reach out to far-flung locations, even to submarines. We’d advertised through newspapers asking private players to help us disseminate NPL-time to the public. Five companies approached us and we’ve selected IFR,” Dinesh Aswal, director, NPL, told The Hindu .

http://www.thehindu.com/todays-paper/tp-national/coming-huge-towers-to-publicise-right-time/article23377284.ece

Click here to view this article at the Southgate ARC.

The XHDATA D-808 and longwave: how to build an effective antenna

Many thanks to SWLing Post contributor, Mad Radio DXer, who writes:

I said I would share my results for attempting to receive LW signals on the XHDATA D-808, & if I can use a longwire to improve reception on this radio. This was after posting videos when I used around 50 metres of longwire connected to the D-808 for improved Medium Wave reception & to prove it works.

This first video shows that it is not possible for LW, no matter if I connect the 50 metres longwire to the 3.5mm input or the whip antenna. I also compare reception of the same station with the Degen DE1103 PLL using the 3.5mm input. The Degen DE1103 still had better reception even when I used the whip antenna extended at the very minimum when using the LW/MW external antenna trick. I know I should have used the internal ferrite antenna of the Degen compared to the D-808, but in any case I did try off camera & reception was about the same. So unfortunately the D-808 was never going to win this round.

However, there is a solution.

The answer? Build yourself a Long Wave induction antenna as shown in the second video [below]. I made one some time ago, as I grew frustrated at how poor the Tecsun radios were on this part of the band & that there were no LW induction antennas available to buy. I tried a signal on 207 kHz which is RÚV Rás 2 from Iceland. Either a radio with a very good internal antenna or a good external antenna is needed to receive this station at my QTH in southern England.

Placing the D-808 on the induction antenna resulted in a very pleasing result, which was it did get reception of Iceland on 207 kHz. So this shows that it is possible to DX on the LW bands with the D-808 with some “external help”.

For anyone interested making a LW induction antenna as shown above, here is a link to a video that has basic instructions & further results. It may be a very simple build & finish what I did, but for me the most important thing is that it works.

I hope my comments & videos will be a great help to all. Happy DXing.

Regards,

Mad Radio DXer.

Excellent–your comments and videos are most welcome! There are quite a number of SWLing Post readers who are avid longwave DXers. I love the simplicity and efficacy of your longwave antenna–something anyone could build.  A clever upgrade to the affordable D-808. Thank you for sharing!

Addendum: More Notes on the HF+ SDR on Medium Wave & Long Wave

In my recent post on the AirSpy HF+ vs Elad FDM-S2, I commented on medium wave reception only.

This past weekend I swapped out the Wellbrook ALA1530S+ for another Wellbrook loop, the ALA1530LN Pro. This LN Pro model is less likely to overload receivers at my suburban Tacoma, WA location. Both AirSpy and Elad radios performed admirably with the LN Pro and it was nearly impossible to find any reception differences on medium wave.

Before the antenna swap though I experimented with inline attenuation modules (“bullets”), typically used in cable TV installations. I used the same sample rates on the SDRs as described in the previous article. After some tests with different attenuation levels, I came to the following conclusions during daytime comparisons:

FDM-S2 with ALA1530S+ loop, medium wave: needs a minimum of 6 dB attenuation to avoid overloading. Anything less causes saturation of the spectrum & waterfall, “crunching” overload noises, and minimal or no received signal.

HF+ with ALA1530S+ loop, medium wave: I had to search diligently to find any signs of false signals or overloading, but finally noticed a weak image or spur of a S-9+60 dB (-13.5 dBm) local station on 1560 that was appearing very weakly on 1270 kHz, mixing with the station on that frequency. Sometimes it was there, other times the spur or image would drop down and disappear, leaving the 1270 signal alone. If I added just 3 dB of attenuation in the antenna’s feed line, the interference from the 1560 station was gone for good. The S-9+60 dB station is a very strong signal; it’s impressive that the AirSpy HF+ deals with this and similar powerhouse signals so well.

Long wave: Below are two screen captures from my local long wave reception in the evening, made moments apart with each receiver.

FDM-S2

HF+

As you can tell, there are a half dozen or so additional signals seen on the HF+ below 200 kHz that do not appear on the FDM-S2. These extra spikes are images or spurs from medium wave signals that were missing from the FDM-S2’s reception–bravo Elad! However, the remaining spikes on both radios below 200 kHz seemed to be noise or interference.

Each receiver had roughly equal performance in the bulk of the long wave spectrum, when I did A-B comparisons on the same beacon signals. I’m not a LW or NDB DXer however, so I can’t claim any expertise on these frequencies. In short, though, both radios seem neck-and-neck from about 200 to 500 kHz.

The DXer of LW frequencies may want to look elsewhere for a better performing radio than either the FDM-S2 or HF+. SWLing Post reader Tudor Vedeanu has commented that the SDRPlay RSP1A  and the Eton E1 work very well at long wave.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington.  He’s a regular contributor to the SWLing Post.

WI2XLQ: Brian Justin’s annual longwave broadcast Dec 24-26

Canadian Reginald Aubrey Fessenden in his lab believed circa 1906 (Source: Radio Canada International)

Now an annual Christmas tradition, Brian Justin (WA1ZMS) will put his longwave experimental station WI2XLQ on the air to commemorate the 110th anniversary of Reginald Fessenden’s first audio transmission.

WI2XLQ will be on the air from 17:00 UTC Dec 24th on 486 kHz and run for 48 hours until 16:59 UTC on Dec 26th.

Listener reports may be sent to Brian Justin, WA1ZMS, at his QRZ.com address.

If you would like more information about Brian Justin and WI2XLQ, check out our interview with him in 2013. Indeed, I successfully heard the 2013 WG2XFG broadcast and posted this audio clip on the Shortwave Radio Audio Archive.

Additionally, SWLing Post reader, George Stein has a very personal connection with radio pioneer, Reginald Fessenden: click here to read his story.