Monthly Archives: August 2019

The Ham Radio Workbench 12 VDC Power Distribution Strip Kit

I had a number of important plans and goals yesterday which I conveniently set aside to build kits instead. Have you ever had one of those days?

Building kits is a little like therapy for me. I find it relaxing, fun, and it gives me an opportunity to tune out everything else in the world while that soldering iron is hot.

The first kit I built was one I purchased this year at Hamvention: the Ham Radio Workbench 12 VDC Power Distribution Strip.

I’ve been on a search for two types of fused Anderson Powerpole distribution panels: a portable one for the field with at least 4 ports, and a large one for the shack with 12-16 ports and at least two USB 5VDC ports.

Sadly, there is no large one on the market that I would like right now. I checked every vendor at Hamvention and the Huntsville Hamfest this year and while there are large panels available, none of them have USB ports. That and the price for a 12-16 position DC distribution panel can easily exceed $120.

As for the small panels for field use, many of them are a bit too bulky and pricey. The inexpensive ones lack individually fused ports.

My buddy Dave (K4SV) knew I was on the hunt, so at Hamvention he directed me to the Ham Radio Workbench podcast table. There, I found the ideal portable solution in kit form.  And the price?  A whopping $25.

Take my money!

Yesterday, I built the kit in near record time. It went together so fast, I forgot to take progress photos.

What I love about this DC distribution kit is it actually has more features than other products on the market:

  • There’s a green LED to indicate power has been applied to the panel and a red LED to indicate any faults
  • Each position is individually fused with standard blade fuses
  • Each position also has a red LED to indicate if the fuse has blown

I also love the size and configuration.

The kit does not come with an enclosure or base of any sort, so I had planned to simply attach it to a dielectric plate to prevent the bottom of the board from shorting on a conductive surface.

This morning, however, I discovered a 3D-printed enclosure from Rocket City 3D:

This enclosure protects the entire panel on all sides so I’ll be able to throw it in my backpack and not worry about the connectors snagging on other items. The price is a reasonable $12 shipped. Done!

This little DC panel pairs well with the 4.5 aH Bioenno Lithium Iron Phosphate battery I purchased on sale at the Huntsville Hamfest. Together, they’ll power the portable SDR system I’m putting together. More on that in a future post! Stay tuned!

Click here to check out this kit at HamRadio Workbech. It’s currently out-of-stock, but you might contact HRW and see if a future run is in the works. Click here to check out the custom enclosure from Rocket City 3D.

UPDATE: I understand Ham Radio Workbench may eventually print the circuit boards for this project. In the meantime, another affordable option I’ve used is this pre-built panel from Electro Sales on eBay: https://ebay.us/UyJPkh


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Next on Encore: Classical Music on Shortwave

Encore – Classical Music on Shortwave – Broadcast on Sunday afternoon in Europe and USA

Encore – Classical Music this weekend is being broadcast as usual by Channel 292 (Europe) on 6070 kHz at 15:00 UTC Sunday 25th August.
And by WBCQ on 7490 kHz at 00:00 – 01:00 UTC Monday 26th August
There is a repeat on 6070 kHz on Friday 30th August at 19:00 UTC.
This week’s show has quite a lot of Xylophone, but also a Strauss lieder, some Tchaikovsky, Schubert – a piano duet played by Richter and Britten (people forget what an extraordinary pianist Britten was).
There will also be some Vivaldi, Debussy, and a treat from Brahms to finish with.
Both Channel 292 and WBCQ do live streams if the reception is poor in your location. Easy to find their sites with a google search.
Thank you for spreading the word about Encore – Classical Music on Shortwave. And thank you to everyone for letting us know how well/badly the signal is received where you live.
Brice Avery – Encore – Radio Tumbril.
Regular Broadcast times are:
15:00 – 16:00 UTC Sunday, and repeated 19:00 – 20:00 UTC Friday on 6070 kHz (Channel 292 Germany).
00:00 – 01:00 UTC Monday on 7490 kHz 9WBCQ – Maine).
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AirSpy HF+ Discovery: First Impressions on Medium Wave vs. Elad FDM-DUOr

The highly anticipated AirSpy HF+ Discovery SDR has been in the hands of early adopters for about two weeks–and I’ve seen nothing but positive comments!

After a long run (2007-2013) with a Microtelecom Perseus, my SDR of choice became the Elad FDM-S2, and more recently an Elad FDM-DUOr “hybrid” SDR receiver. The two Elads have the same core processing components and identical performance when the DUOr is connected via SDR software.

This week I’ve compared the HF+ Discovery ($169) against the FDM-DUOr ($899) using Studio 1 software and identical modes & settings. The following video features the radios’ performance on a crowded daytime medium wave band from suburban Seattle-Tacoma USA.

Click here to view on YouTube.

Notes:

  • Software used is two “instances” of Studio 1, version 1.06e
  • Antenna is an east-west oriented Wellbrook ALA1530LNP Imperium loop
  • Mode, filter bandwidth, AGC, etc. are the same for each radio
  • 768 kHz sampling bandwidth used for both receivers

Stations tuned are:

  • 1320 KXRO Aberdeen WA, 74 miles @ 5 kW (in-line with antenna)
  • 1110 Oak Harbor WA, 78 miles @ 500 watts (in antenna’s null)
  • 1040 CKST Vancouver BC, 147 miles @ 50 kW (in antenna’s null)
  • 1430 KBRC Mt. Vernon WA, 85 miles @ 5 kW (in antenna’s null)
  • 750 KXTG Portland OR, 118 miles @ 50 kW (in antenna’s null)

I purposely sought out signals difficult to hear in the presence of powerhouse stations. Only 1320 kXRO (in-line with my antenna) and 750 KXTG are what you might consider average or fair quality signals. Headphones are recommended for most of these, particularly 1040 kHz.

You’ll note that the pass band has been “pulled” over the edge of the carrier frequency by a few hundred Hertz. This is an excellent trick that can often reduce noise and/or improve intelligibility. It’s a feature unique to Perseus, Studio 1, and SDRuno software; it works in sideband modes and in selectable sideband Sync AM (SAM) mode.

After listening to the signal comparisons, what are your thoughts on the HF+ Discovery? Please leave your comments below.

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

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SAQ receives 438 listener reports

Grimeton VLF mast

(Source: Southgate ARC)

Alexanderson Alternator station SAQ says it received 438 listener reports — ‘an incredible amount’ — for its June 30 Alexanderson Day transmissions from Sweden including 8 ‘super’ DX reports, five from the USA and three from Canada.

The historic electro-mechanical transmitter, which dates back to the 1920s, is fired up periodically throughout the year on 17.2 kHz.

“We are very thankful for all your enthusiastic and positive feedback, with images, recordings, videos, and even Morse ink writer strips,” SAQ said.

The station is a World Heritage Site in Grimeton, Sweden and SAQ’s June 30 message commemorated the 100th anniversary of the first east-to-west transatlantic voice transmission from the Marconi station in Ireland to Cape Breton Island, Nova Scotia.

SAQ has posted an interactive map showing the locations of all received listener reports from recent transmissions and video of the Alexanderson Day transmission event has been posted to its YouTube channel.

https://www.youtube.com/user/AlexanderSAQ/videos

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Guest Post: Decoding Inmarsat L-Band AERO and STD-C messages using the SDRplay RSP SDR

Many thanks to SWLing Post contributor, Mike Ladd (KD2KOG), who shares the following guest post. Note that the following tutorial is also available as a PDF (click here to download).


Basics to decoding Inmarsat L-Band signals using the RSP SDR

by Mike Ladd

Note: CHECK WITH YOUR LOCAL LAWS BEFORE DECODIING ANY SIGNALS FROM THE INMARSAT SYSTEM

Hardware used

SDR: RSP1a SDR from SDRplay? https://www.sdrplay.com/rsp1a/

Antenna: Modified GPS patch antenna for L-Band from SDR-Kits, model A154.? https://www.sdr-kits.net/L-Band-Receive%20Antenna

Software used

SDRuno v1.32
https://www.sdrplay.com/downloads/

VBcable (Donationware) vPack43
https://www.vb-audio.com/Cable/

VAC (Paid for use) v4.60
https://vac.muzychenko.net/en/

JAERO (Free) v1.0.4.9
https://github.com/jontio/JAERO/releases

Tekmanoid STD-C Decoder (Paid for use) v1.5.1
Requires Java JRE, check your local laws before using this decoder.
http://www.tekmanoid.com/egc.shtml

https://www.java.com/en/download/

Introduction

(some text taken and edited from the RTL-SDR Blog website)

This document is not a definitive guide to Satcom, L-Band transmission or the Inmarsat system. This is a collection of information that I have found scatter throughout the internet and re-compiled into a document, this document. My aim is to help you get started and hopefully guide you in the right direction. Expect typographical mistakes, inaccuracies, or omissions

Inmarsat is a communications service provider with several geostationary satellites in orbit. Inmarsat provides services such as satellite phone communications, broadband internet, and short text and data messaging services. Geostationary means that the Inmarsat satellites are in a fixed position in the sky and do not move.

The Inmarsat 3-F(x) satellites have transponders transmitting data in L-Band (1.5 GHz) that can be decoded. 

The modes we will cover in this document are Aeronautical (Classic Aero or ACARS) and Inmarsat-C (STD-C) using an RSP1a, RSP2/2pro or RSPduo connected to the SDR-Kits modified L-Band patch antenna. The Inmarsat system is not limited to only these types of networks. We are limited to the decoders available.
https://en.wikipedia.org/wiki/Inmarsat

Some regions that use the I-3 satellite services moved and migrated to the Inmarsat I-4 Satellites.  See the following document.  https://www.inmarsat.com/wp-content/uploads/2018/09/INM_C_I3_I4_migration_guide_V3.0.pdf

Two of the most popular decoding applications are JAERO used for ACARS and Tekmanoid STD-C Decoder used for decoding STD-C NCS transmissions on the Inmarsat 3-F(x) satellites

https://www.sigidwiki.com/wiki/Inmarsat_Aero

https://www.sigidwiki.com/wiki/Inmarsat-C_TDM

Software installation

Virtual Audio Cable: A virtual audio cable allows you to pipe audio from application (SDRuno) into another application (a decoder like JAERO) digitally. I will assume SDRuno is already installed with your device attached and functioning properly. 

You can now download a virtual audio cable package.  If you already have a virtual audio cable package installed, you can skip to the next section. If you don’t have a virtual audio cable application installed, you only need to choose one and only install one of the two, either one works fine

Close any running apps, install the virtual audio cable and reboot your computer. When your computer boots back to your desktop, your computer will now have a virtual audio cable pair installed on the system. 

You can verify by going to your Control Panel and double clicking the Sound icon. VB-Cable and Virtual Audio Cable will only install a single virtual audio cable pair, one is for the input (Recording) and one is for the output (Playback). A single pair is all that is needed (as shown below).

JAERO

(some text taken and edited from the JAERO website)

JAERO is a program that decodes ACARS (Aircraft Communications Addressing and Reporting System) messages sent by satellites (in this case Inmarsat) to Airplanes (SatCom ACARS). This is commonly used when airplanes are well beyond VHF range. 

JAERO also allows for decoding and demodulation of voice calls, due to local laws and privacy, I will not show or discuss how to do this. You can find more information about that JAERO feature online.

JAERO can be downloaded from the link provided on the first page of this document. After downloading the installer, simply double click the setup file and install it on your primary drive.

Tekmanoid STD-C Decoder

(some text taken and edited from the USA-Satcoms website)

Inmarsat STD-C is a data or message-based system used mostly by maritime operators. An Inmarsat C terminal transmits and receives on L-Band to various geosynchronous satellites that service each major ocean region. 

The Tekmanoid STD-C decoder will decode STD-C Inmarsat EGC (enhanced group call) and LES (land earth station) messages. Some of these messages contain private information. Reception of these messages may not be legal in your country; therefore, your local laws should be checked.

The Enhanced Group Call (EGC) service is a message broadcast service with global coverage (except the poles) within the Inmarsat-C communications system. Two of the services provided are:

FleetNET and SafetyNET

FleetNET is used to send commercial messages to individuals or groups of subscribers (for example, individual companies communicating with their own Mobile Earth Stations (MES). SafetyNET is used for broadcasting Maritime Safety Information (MSI) such as Navigational warnings, meteorological warnings, meteorological forecasts and other safety related information (including Distress Alert Relays) from official sources.

The LES station acts as an interface (or gateway) between the Inmarsat space segment and the national/international telecommunications networks. 

The Tekmanoid STD-C decoder requires Java JRE in order to run. The link for the Java runtime environment is on page 2 of this document. For information contact the developer direct admin@tekmanoid.com

There are alternatives to using the Tekmanoid STD-C decoder, but in my opinion the other decoders available do not perform as well on low end systems or even work without needing “helper” applications to be installed. Tekmanoid STD-C decoder is very easy to use and works great on my low-end system using minimal system resources.

Putting all the pieces together

ACARS and STD-C messages will transmit via the Inmarsat satellite deployed within your coverage area/region, you will need to choose the Inmarsat satellite that is closest to your coverage area. 

Note that only different frequencies are used between ACARS transmissions and STD-C transmissions. You will only need to receive from one of the available 3-F(x) Inmarsat satellites. 

L-Band ACARS transmissions are in the 1.545 GHz range but STD-C messages are on fixed frequencies (shown on page 8)

Since STD-C transmissions are broadcasted on fixed frequencies, we want to monitor the TDM NCSC channel, again these are fixed for the following Ocean Regions. Choose the region closest to your location (page 9).

Again, some regions that use the I-3 satellite services moved and migrated to the Inmarsat I-4 Satellites.  See the following document.  https://www.inmarsat.com/wp-content/uploads/2018/09/INM_C_I3_I4_migration_guide_V3.0.pdf

STD-C transmissions are broadcasted on fixed frequencies, NCSC channel. The NCSC frequency per region is noted below.

Inmarsat satellite: Inmarsat-4 F3 (AOR-W)
Direction: 98° West
Frequency: 1.537.70 GHz

Inmarsat satellite: Inmarsat-3 F5 (AOR-E)
Direction: 54° West
Frequency: 1.541.45 GHz

Inmarsat satellite: Inmarsat-4 F1 (IOR)
Direction: 25° East
Frequency: 1.537.10 GHz

Inmarsat satellite: Inmarsat-4 F1 (POR)
Direction: 143.5° East
Frequency: 1.541.45 GHz

I will assume you have located the Inmarsat satellite that covers your region. I suggest using a compass on your mobile phone to pinpoint the general direction. The direction is in ° (degrees). I am referencing true north, not magnetitic north (traditional analog compass). https://en.wikipedia.org/wiki/Magnetic_declination

You can also download an app for your smartphone called Satellite AR (Android and IOS). After you locate the correct direction of the Inmarsat satellite, you will want to place the L-Band patch on a flat metal surface. I have read that the receive pattern of this patch antenna is z (about 85-90°, straight up). Point the top of the antenna facing the Inmarsat satellite. Using the roof of my car worked just fine, just remember to point the front of the antenna at the satellite.

https://www.u-blox.com/sites/default/files/products/documents/GPS-Antenna_AppNote_%28GPS-X-08014%29.pdf

Launch SDRuno and click the PLAY button, remember that if the RSP(x) is in ZERO IF mode, give frequency separation between the VFO (top frequency) and LO (bottom frequency). In LOW IF mode this is not needed. I suggest running a sample rate of 2 MHz, larger bandwidths are not needed. 

The SDR-Kits patch antenna requires that the RSP(x) Bias-T be enabled. The Bias-T option is enabled within the MAIN panel of SDRuno. See the SDRuno manual located here. https://www.sdrplay.com/docs/SDRplay_SDRuno_User_Manual.pdf view page 17.

With the Bias-T enabled. Set the RSP(x) RF GAIN to max. The RF GAIN slider is located on the MAIN panel. See the SDRuno manual located here. https://www.sdrplay.com/docs/SDRplay_SDRuno_User_Manual.pdf view page 17.

For more information about the RF GAIN settings of the RSP(x)
https://www.sdrplay.com/wp-content/uploads/2018/06/Gain_and_AGC_in_SDRuno.pdf

Select the Virtual audio cable as the output in SDRuno, this is selected via the RX Control panel. SETT. button and clicking on the OUT tab.

Have SDRuno’s Volume slider (RX Control) at about 35-40%

Upper sideband is recommended but I found the best mode to use for L-Band ACARS or L-Band STD-C decoding is DIGITAL with a filter width of 3k. 

Be sure to set a proper step size (right click the RX Control frequency readout). The step size is not important for STD-C transmissions because these signals are only on one frequency for the satellite in your region but L-Band ACARS signals will be on many frequencies. Setting the proper step size will avoid issues when you point and click on signals you want to decode using the JAERO decoder.

You will want to center the signal with a little breathing room within the AUX SP filter passband. The filter slopes are very sharp. Keep the signal centered and away from the extreme edges (red markers). 

Select your virtual audio cable within the decoder’s audio input preferences.

The Tekmanoid STD-C decoder sound properties are located under Settings in the toolbar menu.

JAERO’s sound settings is located under the Tools menu and Settings.

For STD-C decoding use the frequency from page 8 of this document, remember we only want to monitor the TDM NCSC channel in the Tekmanoid STD-C decoder.

For JAERO decoding, I suggest you start in the 1.545 GHz portion and observe the constellation in the JAERO decoder. 

The signal to noise ratio (SNR) needed for successful decoding in these decoders will need to be greater than 7dB. When working with a weak satellite signasls, try decimating the signal using SDRuno’s decimation feature. (MAIN panel, DEC).

Click here to view on YouTube.

Additional resources

Videos:

Click here to view on YouTube.

Click here to view on YouTube.

Click here to view on YouTube.

Click here to view on YouTube.

SDRuno:

L-band frequency bank
https://mega.nz/#!jRFRiSaA!CcmRRRpjToxPzyGV9bf7MkDkKnqCYZCwwjC5curWj6g

PDFs:

https://www.inmarsat.com/wp-content/uploads/2018/08/Aero_Service_External_Com_Kit_I3_to_I4_Transition_21AUG2018.pdf

http://seaworm.narod.ru/12/Inmarsat_Maritime_Handbook.pdf

Websites:

https://usa-satcom.com/

https://uhf-satcom.com/

I hope this document helps you get started decoding Inmarsat L-Band transmissions from the I3-F(x) satellites. I am sure I missed some key features, remember this is only a primer/basics to decoding these types of transmissions.

Warmest of 73,
Mike-KD2KOG


Many thanks for sharing your tutorial here on the SWLing Post, Mike! This looks like a fascinating activity that really requires little investment if one already owns an RSP or similar SDR. I’m certainly going to give L-Band a go!  Thank you again!


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Please Take Action: DOD Broadcast and Listener Survey on WWV and WWVH

A WWV Time Code Generator

Many thanks to SWLing Post contributor, Dennis Dura, who shares the following note from Paul English (WD8DBY), Chief, Army MARS:

DOD Broadcast and Listener Survey on WWV and WWVH

From 14-24 August, WWV and WWVH will be broadcasting a DOD message at 10 mins past the hour on WWV and 50 mins past the hour on WWVH. As part of the message, all listeners are asked to take a listener survey at the URL specified in the message.

www.dodmars.org/home/wwv-survey

The results of this survey are shared with WWV/H personnel to show their NIST chain of command how often their stations are monitored and how the various timing signals and messages are used by the listeners.

Please take a listen to this message and take the survey…as the saying goes, “every vote counts” and your input to this survey is being used to help demonstrate the importance of these stations.

Thanks for your consideration in this effort.

Paul English, WD8DBY
Chief, Army MARS

Many thanks for sharing this, Dennis. Readers have also shared this ARRL News item urging listeners to take the DOD survey.

If you appreciate WWV/WWVH, please take a moment to complete this short survey.

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Trial Run of WWV Special Event Station August 24 & 25

WWV’s transmitter building in Fort Collins, Colorado (2014)

(Source: ARRL via Eric McFadden)

WWV Centennial Committee Prepares for Trial Run of WW0WWV Special Event

The WWV Centennial Committee reports that it will conduct a trial run of special event station WW0WWV over the August 24/25 weekend.

Radios and antennas began arriving last week, and a tower and beam will be erected, along with several vertical antennas. WW0WWV will be set up adjacent to the WWV transmitter site in Fort Collins, Colorado. WWV turns 100 years old on October 1.

“We’ll be testing band and notch filtering, in an attempt to reign in the extreme RF environment created by WWV and WWVB,” said Dave Swartz, W0DAS, of the Northern Colorado Amateur Radio Club (NCARC).

The club will carry out the special event operation in conjunction with the WWV Amateur Radio Club and the National Institute of Standards and Technology (NIST), which operates WWV/WWVH/WWVB.

The special event site is within 1/3 of a mile of all six WWV transmitters and the 50 kW WWVB transmitter. “On-air tests will start Saturday afternoon, August 24, and run through Sunday, August 25,” Swartz said, adding that organizers will post specific times and frequencies on the WWV Centennial Committee website.

The WWV Centennial special event is set to run from September 28 through October 2, and round-the-clock operation will take place on CW, SSB, and digital modes. Operations will shift among HF bands following typical propagation and will include 160 meters as well as satellites (SO-50, AO-91, and AO-92) and 6-meter meteor scatter.

Up to four stations will be on the air for routine operations. A fifth station will schedule contacts with schools, universities, and museums, as well as conducting unscheduled contacts. The additional station will periodically broadcast an AM carrier from a radio locked with WWV’s 10 MHz signal.

“At this point we have filled our operator’s slots and met equipment goals, but we need more financial resources to cover basic operating expenses, return shipping, and site logistics,” Swartz said. Members of the Amateur Radio industry have contributed equipment, including radios, amplifiers, and antennas.

NIST has announced that it will not be able to open the doors of WWV to the public for the event. “Due to a number of reasons, the scope of the formal celebration will be limited to only 100 invited participants,” the WWV Centennial Committee announced. “WW0WWV will be the main public event for the centennial celebration.”

Visit the WWV Centennial Committee website at http://wwv100.com/ to see how you can get involved.

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