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COAA Beaconsee and COAA Radio Clock

COAA Beaconsee and COAA Radio Clock

MT COAA Software Gold Mine Part II: and BeaconSee REVIEW By John Catalano

s I wrote last , I have found the A Radio Timepiece to Tune Centro de Observação Astronómico Most of us remember, with nostalgia, our For our first attempt we’ll tune to a time A no Algarve (COAA) website to be a early days of radio monitoring when we first station with a strong signal and minimal signal “gold mine” filled with many interesting and heard the rhythmic pips of a fading. From the Command menu under the unique radio programs. Last time, we explored station. In the USA it was WWV and its sister “Transmitter” menu, select the time station you just two COAA “veins”: OrbcommPlotter and stations, although CHU was my first are monitoring. This automatically selects a PlanePlotter. logging. In Europe you probably listened to MSF decoder mode to match the station’s digital time OrbcommPlotter easily qualifies as a unique from Rugby, England, or DCF77 on encoding method. label. It is the only program I know of that tracks . In Asia you had RWM from Now look at the top right of Figure 1. and decodes signals from low earth orbiting satel- and in VNG. Just about anywhere on There you will see a broken vertical line. Tune lites (LEO). And, if it has to do with tracking and the globe you can receive a time standard sta- the receiver so that the horizontal white dashes plotting commercial aircraft, PlanePlotter is up tion. pass through the line break. makes to the job with its decoding and plotting of VHF Feeding the audio signal from any of these Setup and tuning very simple. ACARS and HF ACARS signals. Selcal decoding time stations into COAA’s Radio Clock program Going back to my listening roots, I used and direction finding and plotting are also part of will guarantee that your PC’s clock will be syn- CHU Canada on 3330 kHz. Figure 1 shows Radio the PlanePlotter package. chronized to an atomic time standard. Then all Clock displaying CHU audio. Using the PC’s There is much more gold to be had on the PC time-sensitive applications will be “on-the- mixer screen and receiver output (if variable), COAA site … if we keep digging. money.” adjust the level of the source until it appears as in Figure 1. Too high a level and the pulse will not ❖ Simultaneity just a Phantom be cleanly formed and noise will fill the Setting our PC clock to the “correct” time Let’s get right into it. Download the free between the pulses. can be very important. It’s the difference between 500kB program from the COAA website www. Once correctly tuned and the level set catching that rare scheduled DX or just hearing coaa.co.uk/radioclock.htm. Running this self- properly, allow the program to run for a hiss. But one of the conclusions drawn from extracting program will lead you through the or two. When the program synchronizes to the Einstein’s of relativity is that there is no simple and quick setup procedure. Connect the station’s data, the small windows at the bottom such thing as an occurring exactly simul- audio output of the receiver to the PC’s sound- of Figure 1 will display some interesting data. taneously for two separated observers. Not even card’s mic or line input. Using the soundcard First, the program’s last reset time, in our case, setting two . mixer screen, ensure that the input is not muted 10:03. Next are the synchronized time and our Why? Well, to start with, there is no preferred and is set to mid level. The mixer screen can be GMT offset, 10:03:30 [UT-05]. And finally we . Wherever each of the observ- accessed from the Control Panel or via a right see our PC’s clock time, 10:03:28. Comparing ers is in (x,y,z) and time(t) is the “correct” mouse click of the speaker icon in the lower right the last two windows shows that the PC clock is location, and will have a constant speed at program tray. 2 behind real time. each location. That’s just the starting point for Soundcard calibration is a major part of the We can use this info to manually set the PC’s evolving the concept. But suffice it to say, simul- setup program. It all happens automatically with clock to the “exact” . If you want (or need) taneity does not exist, and setting two clocks to just a mouse click or two. One more setting and continuous automatic PC clock setting, you’ll exactly the same time is not possible. we’re done with set-up. have to pay 25 euros to register the program. The key word is “exactly.” In the space-pa- Time stations use Coordi- This will enable the automatic PC clock setting rameter tolerances of our everyday lives, we can nated (UTC) or (GMT) function. neglect the extremely small difference and call an standard for their time “zone.” GMT is defined The program’s excellent Help file has a event simultaneous. But remember, we are defin- as the time at 0 degrees , called the wealth of information. Here is what it says about ing our own “,” which is different from the . UTC is a similar standard, but CHU, “Unlike the other signals decoded by Ra- reality of the . (Perhaps you can use this uses terrestrial and celestial co-ordinates. For our dio Clock, CHU (Canada) uses a single sideband fact of Einstein relativity on your boss next time purposes the two are equal. transmission with re-inserted carrier. As such, it you are late to a meeting …that is, if he is not a Radio Clock automatically converts UTC/ can be received in AM mode as well as SSB. If .) GMT to the PC’s local once we enter SSB or CW mode is used, the tuning does not Now having said all that, how would you like how many our time zone is offset from need to be offset in order to recover the correct to have a free program that sets your PC’s clock to GMT. We are now ready to go about the business data tones, which encode the time information. the “exact” time of a cesium ? OK, of radio monitoring. The time code is contained within a 300 bps so it’s not quite exact, but it is really for free! asynchronous data stream transmitted following

Figure 1 - Radio Clock’s one and only display.

68 MONITORING March 2008 the 1 kHz seconds pulses for each of the 31 to purpose of these volunteer operated beacons is to words per minute followed by four one-second 39 seconds in each minute. The minute marker “… help amateur and commercial dashes. The callsign and the first dash are sent at is a full second of 1 kHz tone.” radio users assess the current condition of the 100 watts. The remaining dashes are sent at 10 Don’t miss exploring Radio Clock’s Help ionosphere.” watts, 1 watt and 100 milliwatts.” The decreas- file. The NCDXF website www.ncdxf.org/Bea- ing power levels add another dimension to the con/BeaconSchedule.html provides location, resulting propagation information. Time’s Up callsigns, sample audio files and current opera- Each beacon transmits every three min- I enjoyed using Radio Clock and decoding tional status for each beacon. This is their descrip- utes, twenty-four hours a on an exacting different time signals on short and long wave. tion of a beacon transmission, “A transmission time schedule. However, this is done in a pre- The only problem I encountered was a displaced consists of the callsign of the beacon sent at 22 determined sequential pattern with one beacon display as seen in Figure 1. No starting immediately after the other what program or PC dis- has finished. Each transmits for ten play setting I tried, the result was seconds during its allocated time the same. The spectrum display period. was pulled to the right and the The beacons use four frequen- lower right operation windows cies, 14.100, 18.110, 21.150 and were not fully open. This was just 28.200 MHz, but not at the same a minor irritation in an excellent time. For example, once all beacons program. have had their 10 second transmis- Radio Clock is free, so give sion on 14.100 MHz, they all move it a try. It’s a nice meld of radio up to the next frequency, 18.110 monitoring and useful computer MHz, and again start their sequential application. Now let’s dig for transmissions. another nugget. The key to utilizing this meth- odology is accurate timing. The PC which is controlling your receiver’s ❖ “Seeing” frequency must have its time set Propagation in accurately. If it is off, it will be “looking” on frequencies for trans- Real-time missions that have long ago ended. The Northern California Hummm, accurate tim- DX Foundation, NCDXF and ing. Sound familiar? This is where the International Amateur Radio COAA’s Radio Clock can set your Union, IARU, have set up eigh- PC’s time accurately so you will be teen shortwave beacons at various Figure 2 – BeaconSee’s full screen during set-up. on the right frequency at the right locations around the Earth. The time.

March 2008 MONITORING TIMES 69 Beacon Hopping unzip and then install it. While you are at it, as seen by the blank area. The Sri Lanka 4S7B If you have one of the listed controllable also download BeaconMap from the COAA beacon shows similar propagation conditions receivers, COAA’s program BeaconSee will website. This program produces a map for these two bands. keep step – in frequency and time – as the displaying the location of the beacon stations. This means that at this time, from this beacons “do their thing.” Using the receiver’s Install it in the BeaconSee directory. receiver location, frequencies around 14 MHz audio and some fancy calculations (fast Fourier Trying to run the program on a Windows are the place to look for transmissions from transforms), the program produces a spectrum Vista PC gave me problems. (Thank you, Vista, (Scandinavia) and Sri Lanka (South display for each beacon. The received signal yet again!) If you are using Vista, I suggest that Asia). Conversely, right now, forget about 21 strengths are plotted for each beacon versus you run the program under the Windows XP MHz for monitoring these areas of the world. frequency and time. This gives the user an compatibility. Do this by right clicking on the Now look under the LU4AA column. accurate, real-time, visual representation of BeaconSee, BeaconMap and Help files. Then This Argentine beacon has just the opposite ionospheric propagation conditions over the choose “Compatibility,” Windows XP (Service propagation results. LU4AA’s 21 MHz signal entire shortwave spectrum. Now what SWLer Pack 2) and select “Apply.” After performing is much stronger than its 14 MHz. Remember, or ham couldn’t use that? Let’s see more about this, the programs worked fine under Vista. propagation results will always be unique to BeaconSee. the locations of the transmitters and receiver. Seeing More When BeaconSee is run, you’ll be - Seeing the Difference “PSee” Requirements ed with the screen seen in Figure 2. As in Radio Over the I’ve used quite a number As with other COAA programs, Beacon- Clock, all program functions are accessed from of propagation prediction programs. The differ- See requires very little in the way of a PC. A one screen. The layout is also similar, with ence with BeaconSee is that it is the real thing, PC running Windows 95/98/2000/XP, a free Command menus at the top, spectrum display in real-time, not a prediction or guessitmate. serial port and a 16-bit SoundBlaster-compat- in the middle, and small function indicators Assimilating all the information on Bea- ible sound card that supports audio capture at (telling us what the program is doing) at the conSee’s spectrum screen takes a bit of finesse. 8k samples is all the PC that you need. bottom. There is a lot here. But after an or so of For automatic operation, a serially con- From the indicators in Figure 2, we can see use you’ll be surprised how much propagation trolled receiver is required. In my opinion, that we have selected all frequencies sampled information you can glean just from a quick this is only way you should consider using this continuously, with a bandwidth of 100 Hz and look at BeaconSee. program. BeaconSee works with many serially a center frequency of 1000 kHz. BeaconSee is available for free at www. controlled including: Icom, Kenwood, The spectrum display in the center of the coaa.co.uk/beaconsee.htm. If you register the Winradio and Yaesu and the TenTec RX-320. screen looks like a checkerboard. Each of the program for US $29, a number of added func- If your receiver can be controlled via a se- eighteen vertical columns represents a beacon tions are enabled including sampling beacons rial port but is not on the list, it would probably location. The four horizontal rows are the four at periodic interval to get a full 24 hours of work using the “Generic” radio set-up menus. transmit frequencies. This is where the signal and unattended screen savings at user- The details of the receiver’s control command strengths of the beacons will be displayed. defined times. These features will allow you to structure and some patience will be needed. Using the excellent figure from the Help automatically build and save a history of actual Even using listed receivers, you may be file, Figure 3, we focus on just the transmis- propagation conditions from transmitter points required to manually enter a few of the radio’s sions on 14 and 21 MHz from the last nine around the Earth. Just sitting and watching interface parameters, such as baudrate, word- beacons in the chain. BeaconSee is a fascinating activity. width, stop bits and parity setting, and for Look at the column labeled OH2B, the some models the radio’s digital address may Finland beacon. We can see that its 14 MHz be required. ❖ More Plotting signal is a visible bar of good size. However, After downloading this 700kB program, No, I’m not referring to plotting against OH2B’s 21 MHz signal is almost nonexistent Julius Caesar on the Ides of March. I’m talking about yet another COAA program, ShipPlotter. Made in the form of the other COAA plot- ter programs, ShipPlotter decodes and plots maritime AIS, automatic identification system transmissions. All it takes is the program and a radio capable of receiving 161.975 and 162.025 MHz.

❖ More Decoding The DSCdecoder program decodes digital selective calling (DSC) signals used by ships in the MF, HF and VHF bands for distress, ship-to- ship and ship-to-coast station communications. It can also decode Navtex and Vessel Traffic Service (VTS) messages. As for this article, we are out of time. But for coverage of COAA’s ShipPlotter and DSCDecoder in Computers & Radio columns. I hope you’ll now agree, the COAA site is a gold mine of unique radio programs. Try some of them and let me know what you think.

CONTACT INFORMATION Centro de Observação Astronómico no Al- garve www.coaa.co.uk/software.htm + 351 282 471180; [email protected] Figure 3 – Zooming in on part of a working BeaconSee spectrum screen

70 MONITORING TIMES March 2008

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