The BE CON WEST MOUNTAIN RADIO Quarterly Newsletter Quarter 2 - 2019 NEW PRODUCTS! See Page 6 for More Information CLRmodule: DIY DSP Filtering! Pg 2-5 Short Wave Utility Monitoring by Sholto Fisher, K7TMG Pg 6 CLRstereo: Filter Two Stations at Once! New Product Spotlight by Craig Dominski, KC9VFA Pg 7 Hedy Lamarr by Laura Schneider Pg 8-11 Radio Sloyd and the Rebirth of Collegiate Amateur Radio COMING SOON! David Kazdan, AD8Y N8XJK Battery Booster Shortwave Utility Monitoring by: Sholto Fisher K7TMG What are Utility Stations? Where Can I Hear these Stations? Utility Station (Ute) monitoring has The maritime Shortwave bands are been and continues to be a popular and generally harmonically related in a similar integral part of Shortwave Listening fashion to the Amateur bands. A useful “rule (SWL). The term Utility Station refers to of thumb” frequency guide to remember is any transmitting station that is not an 2.1 MHz, 4.2 MHz, 6.3 MHz, 8.4 MHz, 12.6 Amateur or Broadcast station; so it is a MHz, 16.8 MHz, and 22.1MHz. These make very broad catch-all term which covers good places on the radio dial from which Government, Military, Commercial, and to explore. Private transmissions. There are also published lists of various As Shortwave Radio has given way to the Maritime stations you can consult such as internet and telecommunication satellites, William Hepburn’s excellent Telex Broadcast the volume of utility traffic has naturally list, which gives very detailed information decreased but you can still find plenty to useful in identifying and selecting stations monitor on the Shortwave bands even to monitor. in 2019. (Monitoring Government and Military transmissions may or may not The 8 MHz Maritime band is often a very good be legal in your country, so if in doubt, place to start as it is available to most areas consult your national telecommunications day and night. For this reason it is probably body guidelines) the most active band for transmissions. This article is going to concentrate on Most Telex broadcasts will be in SITOR-B monitoring the various Maritime “digital mode. This is more or less identical to our data” stations you will typically encounter Amateur digital mode AMTOR-B (remember on Shortwave. The transmissions you can B for broadcast). It was also widely known monitor include weather reports (SYNOP), simply as FEC when it was a common mode navigational warnings, FAX images, heard on the Amateur bands, and it is positional/situational reports, and general common to hear it described as NAVTEX. information relevant to mariners. They are SITOR-B is a synchronous data stream transmitted in a variety of digital modes so with a symbol speed of 100 Baud. It uses learning how to successfully monitor them Forward Error Correction (FEC) with each will increase your knowledge and ability character repeated to help overcome the in recognizing common modes heard fading typically encountered on Shortwave. on Shortwave. WE WANT TO HEAR FROM YOU! If you would like to submit an article for consideration in future newsletters please contact [email protected] 2 Shortwave Utility Monitoring by: Sholto Fisher K7TMG (Continued from previous page) With a fair signal and good decoding Pactor and CW decoding is currently equipment, it is often possible to get available in F6CTE’s software MultiPSK. 100% accuracy of received text over a All modern decoding software uses your considerable length of time! computer sound card as a capture device. Simply hook up receiver audio to your mic or line-in jack on the pc and you are ready to decode. Figure 1: An extract of William’s list for the 8MHz Maritime band. From William’s list you can also see RTTY 45/170, CW (Morse Code) and Pactor listed as modes used. Figure 2: SeaTTY Decoding a SITOR-B How Can I Decode these Stations? (NAVTEX) Transmission There are a number of software programs NAVTEX messages are numbered and available to decode these transmissions. SeaTTY will organize them into a list by Some are free and some commercial. received time and date. A well regarded program specific to The station DWD (Hamburg) broadcasts Maritime monitoring is the SeaTTY package RTTY SYNOP data 24/7. These are weather available from Sergei Podstrigailo. It is reports coded in WMO format and can capable of decoding SITOR B (Navtex), be automatically displayed by the free RTTY, FAX, GMDSS DSC (HF & VHF) and NavTMsgs companion software for SeaTTY. SAME transmissions (used in the US for There is also a SYNOP decoder in MultiPSK. certain Weather alerts). Pactor decoding in SeaTTY is not currently supported but Sergei is working on an update to include that feature. 3 Shortwave Utility Monitoring by: Sholto Fisher K7TMG (Continued from previous page) Figure 3: NavtMsgs Displaying SYNOP Figure 5: MultiPSK Decoding a Pactor Stations Received by SeaTTY Transmission Station PWZ in Rio de Janeiro uses Pactor mode to broadcast its weather and navigational warning information. Digital Selective Calling (DSC) In the GMDSS (Global Maritime Distress & Safety System) the use of digital selective calling is employed. These transmissions take the form of brief data bursts which contain a variety of information such as safety, test messages and distress. Both SeaTTY and MultiPSK are capable of decoding these. You will see DSC messages from ship or shore stations. Figure 4: SeaTTY Receiving a Kyodo FAX Image Kyodo News (Japan) is the only commercial press transmission left on shortwave radio. There are still plenty of Maritime weather FAX stations operating around the world and in the resources section you can find a complete schedule. 4 Shortwave Utility Monitoring by: Sholto Fisher K7TMG (Continued from previous page) Resources 1. Shortwave Utility Station Monitoring by KC2HMZ https://www.qsl.net/kc2fng/swute.html 2. Worldwide HF Radio-Telex Broadcasts http://www.dxinfocentre.com/ maritimesafetyinfo.htm 3. Worldwide Marine Radiofacsimile Broadcast Schedules https://www.nws.noaa.gov/os/marine/rfax.pdf 4. SeaTTY Digital Maritime Decoder http://www.dxsoft.com/en/products/seatty/ Figure 6: SeaTTY in DSC (HF) Mode 5. SYNOP Companion Program for SeaTTY Help! I Can’t Hear Anything! (English, French, & Dutch) http://home.kpn.nl/da2dr1/navtmsgs/Navt_ If you do not have a very good receiving GB.htm antenna or location, one trick you can employ is to use an online SDR radio 6. F6CTE’s MultiPSK Software Decoder instead. Hook up an audio patch cable http://f6cte.free.fr/index_anglais.htm from your speaker output jack to the mic or line-in jack on your computer and you 7. DWD Hamburg Radio Teletype (RTTY) can decode in exactly the same way! Weather Forecasts https://weather.mailasail.com/Franks- I hope this article has given you a brief Weather/Radio-Teletype-Weather-Broadcasts feeling of what is out there to monitor and some ideas for how to do that. 8. DWD Schedule http://www.ominous-valve.com/dwdschedule. pdf 73, 9. GMDSS Digital Selective Calling Sholto Fisher, K7TMG https://www.sigidwiki.com/wiki/GMDSS_ Digital_Selective_Calling 10. Worldwide online SDR radios https://sdr.hu/ 5 New Product Spotlight: CLRstereo & CLRmodule! by Craig Dominski, KC9VFA Our family of Clearspeech® products is CLRmodule is ideal for those with their expanding! Introducing the CLRstereo own speaker ‘shells’ who wish to upgrade and CLRmodule. to Clearspeech® technology! There are many applications for this DSP CLRstereo is perfect for those who noise reduction unit! use either an advanced radio (with two independent audio outputs), or two Hobbyists can now add to: separate radios simultaneously. This would happen typically when contesting as an • An existing radio that does not have a SO2R station (single operator two radio). factory DSP You can also use it in non contesting • A new “homebrew” shortwave receiver situations as a way to listen to two different or QRP rig radios at the same time e.g. casual • A powered speaker monitoring of two different frequencies/ • A matching external speaker for a radio bands! CLRstereo allows for flexible audio (also requires a small audio power switching so you can listen to Main, Sub amplifier) or both simultaneously! This unit features independent volume, tone and filtering for Manufacturers can: both channels. The CLRstereo unit can be used with stereo headphones or connected • Easily incorporate an audio noise to amplified stereo speakers such as our reduction DSP into a new product COMspkr. Of course, this product has our • Reduce development time by utilizing patented Clearspeech® technology so you a complete DSP solution from West can experience independent DSP noise Mountain Radio reduction for Main and Sub RX or two ® separate radios! Our powerful CLRspeech INTERESTED IN MICROCONTROLLERS? algorithm gives clarity and depth for Check out this page for more info: difficult HF reception! www.westmountainradio.com/pic_resources 6 Hedy Lamarr by Laura Schneider Hollywood Star or Radio Scientist? At first, her idea was laughed at, and people Why not both? told her to “go back to being an actress.” However, everyone came around as they A big name in MGM’s “Golden Age”, Hedy realized just how invaluable her invention Lamarr starred in many films as an actress truly was. Hedy proves that anyone can (Ecstasy, Samson and Delilah), but also be an inventor, if you have the drive and contributed to one of the most crucial passion to make it work! Her system scientific developments of our time. Along allowed for the much-needed security with many other clever solutions, she co- during World War II, but over time it became invented an early technique for spread the foundation of military communications, spectrum communications. This was crucial cellphones and bluetooth! Our wireless to the many wireless communications of our lives are all thanks to Hedy Lamarr and the present day.
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