Spec t ru m Mon i tor Amateur, Shortwave, AM/FM/TV, WiFi, Scanning, Satellites, Vintage Radio and More

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1 T h e Spec t ru m Mon i tor Amateur, Shortwave, AM/FM/TV, WiFi, Scanning, Satellites, Vintage Radio and More Volume 4 Number 6 June 2017 Ya esu FTM-100 DR: A mateur Fr iendly Digital Operating P l u s : E a r l y R a d i o O n-a i r S t u n t s We a k-si g n a l Mo d e s E x p l o r e d F C C R e w r i t e s S o m e Ha m /C B Ru l e s R e p a c k i n g T V s T o p M a r k e t s

2 Top: MSK144 waterfall using the WSJT-X suite as displayed on the author s computer. Below top and bottom: The front and back of West Mountain Radio s RIGblaster Pro USB ($270) USB digital interface for your transceiver. Right: Tigertronics SignaLink ($120) USB radio interface. Both eliminate the need to attach to your computer s existing sound card. (Graphics courtesy: Universal Radio) Using Weak Signal Software to Reach for the Sky! By Robert Gulley AK3Q Occasionally, something comes along in the world of amateur radio that is simply revolutionary. Joe Taylor s weak signal mode software suite WSJT-X, fits squarely in this category. In this article I ll give an overview of the software, highlight some of its many uses, and suggest some applications beyond simple contacts/station loggings. Many have no doubt heard of renowned physicist Joe Taylor K1JT, or at least JT65 or JT9 software. But weak signal mode software has progressed leaps and bounds since the introduction of these modes only a few short years ago, thanks in part to some great contributions from people around the world. The WSJT-X suite of software represents the outgrowth of these modes, and its latest incarnation, v. 1.70, has added even greater capabilities. Here is a brief description of the suite from the WSJT-X Users Guide: WSJT-X is a computer program designed to facilitate basic amateur radio communication using very weak signals. The first four letters in the program name stand for Weak Signal communication by K1JT, while the suffix -X indicates that WSJT-X started as an extended and experimental branch of the program WSJT. WSJT-X Version 1.7 offers eight protocols or modes: JT4, JT9, JT65, QRA64, ISCAT, MSK144, WSPR, and Echo. The first four are designed for making reliable QSOs under extreme weak-signal conditions. They use nearly identical message structure and source encoding. JT65 and QRA64 were designed for EME ( moonbounce ) on the VHF/UHF bands and have also proven very effective for worldwide QRP communication on the HF bands. QRA64 has a number of advantages over JT65, including better performance on the very weakest signals. We imagine that over time it may replace JT65 for EME use. JT9 was originally designed for the LF, MF, and lower HF bands. Its submode JT9A is 2 db more sensitive than JT65 while using less than 10% of the bandwidth. JT4 offers a wide variety of tone spacings and has proven highly effective for EME on microwave bands up to 24 GHz. All of these slow modes use one-minute timed sequences of alternating transmission and reception, so a minimal QSO takes four to six minutes two or three transmissions by each station, one sending in odd UTC minutes and the other even. On the HF bands, world-wide QSOs are possible using power levels of a few watts (or even milliwatts) and compromise antennas. On VHF bands and higher, QSOs are possible (by EME and other propagation types) at signal levels 10 to 15 db below those required for CW. As this description shows there are multiple modes offered in this (free!) software suite, each with a specific application to a particular type of weak signal operation. June 2017 The Spectrum Monitor 19

3 I should mention here that this software is not just for the amateur radio operator, but also for the shortwave radio hobbyist. I have received several QSL (reception reports) card confirmations from shortwave listeners, along with requests for electronic confirmations on eqsl.cc, an online logbook. I confess to initially being something of a skeptic of software like this, particularly of JT65 and JT9 as they were presented to me several years ago. The demonstrator was emphasizing how little one had to do to make a contact, and being an old button pusher and knob turner, there was not much appeal. Recently, however, I was reintroduced to the software by a friend of mine who was mentioning he was close to working DXCC (100 countries confirmed) and had already WAS (worked all states) on multiple bands, having only used the software for several months. Chances are good that if you are an amateur radio operator or an active shortwave listener you know we are in a declining solar cycle, with several years yet to go before hitting the solar minimum. This means that signals are getting harder to come by, made even more difficult by the varying geomagnetic disturbances and solar winds we have been experiencing. After spending many relatively fruitless days tuning around the amateur bands for signals, suddenly these digital modes started sounding pretty good! Software Setup Setup was relatively easy since I already have some experience with digital modes in general, but I will give a few pointers here for those who may be new to interfacing the computer with a radio, as well as a few things to watch out for in terms of audio settings. While the built-in soundcard of a laptop or desktop computer will work for this software, if possible, I recommend having a secondary soundcard source or interface, preferably external, such as the SignaLink USB, RIGblaster, or similar commercial or homemade device. There are plenty of plans on the Internet to make your own interface with a minimum of parts. The reason you want a secondary sound interface is simple you want to be able to isolate the sound input/ output from the regular computer system s sound output to avoid interference with the digital mode encoding/decoding. If you must use the standard soundcard, keep in mind the possible conflicts, and turn off any system sounds you can in order to avoid as much interference as possible. I am constantly surprised by how many times I hear the familiar Windows ding or brringgg sounds being transmitted along with a digital mode signal! Audio level adjustment is the biggest obstacle some folks encounter when setting up for any digital mode, particularly in terms of transmit audio. If your radio will not transmit properly it is likely an audio level setting in the operating system that is the culprit, or an incorrect selection of the audio source. Again, there are countless tutorials online for setting up soundcard interfaces, so I will leave more detailed 20 The Spectrum Monitor June 2017 Settings (Courtesy of the author) explanations to them. As for the software setup, WSJT-X uses a common interface for each of the modes; so that much of the configuration settings will only have to be done once. The User s Guide has specific information for each mode, and good results are likely if followed. Unlike many user s guide, the one for WSJT-X is easy to understand and clear, while still being concise. Almost any modern computer may be used for this software in terms of speed, and minimal memory requirements. Various operating systems and/or versions of the operating system may have different requirements for installing sound interfaces or setting audio levels, but the WSJT-X software itself is basically consistent across operating systems. A critical factor in operating any of the modes provided by this software is the accuracy of your computer clock. You simply cannot rely on it to be set close enough to NIST standards without some utility to regularly check time sources and adjust your clock as needed. The weak signal modes require an absolute minimum of 2-second accuracy, and less than one-second deviation is strongly preferred. There are several free programs to do this, and my program of choice is By all means, if there is a friend or group using the WS- JT-X software already, this can save some time in choosing the proper settings, but I will highlight a few of the more important ones here. Under <File> there is a <Settings> option where most of the configuration takes place. From this category, there are General options, Radio, Audio, TxMacros, Reporting, Frequencies, Colors and Advanced options. The default settings in most cases will be fine, but for CAT (computer) control of the radio you will need to know

4 the COM port, the speed of your port, and the usual data settings for the port. They must match with the radio you are using. If you use other software for CAT control those same settings will work, but be aware only one program can use the COM port at a time. If your logging program uses a COM port for controlling the radio, you will want to make sure you start the WSJT-X program before starting the logging program so that WSJT-X has control of the port. As a side note, at least with my Windows10 system, anything that loads a sound driver often wants to make the speakers the default device, and this sometimes leads to the transmit audio being sent out the speakers rather than the USB Audio CODEC. A minor annoyance, but I have to go into the Control Panel/Sounds panel and change the defaults. Under the <Radio> settings tab the PTT will also need to be set if transmitting, in my case, VOX is selected, but other interfaces may use the COM port or CAT control. In the <Audio> settings tab make sure you do not get confused by the soundcard setting Input requires a Microphone (USB Audio CODEC) input setting, and Output goes to the Speakers (USB Audio CODEC) output. These always refer to the computer side of things they are the reverse from the radio side, as the computer speaker output becomes the radio input, and the computer input is the output of the radio. Using the Programs I will start by discussing the two most popular modes, JT65 and JT9, and then we ll move on to some of the other modes (sample screen top of next column). Once the configuration settings are done and the program is restarted (just a precaution to make sure everything is loading properly), go to <Mode> at the top of the screen and select either <JT65> or <JT9 + JT65>. If your radio has wide enough filters (able to cover more or less the full width of a 3-kHz signal), you can select the <JT9 + JT65> mode which allows for both modes to be received at once. Also, assuming your screen space allows, if it is not already displaying the waterfall, go up to <View> and click on <Waterfall>. Even if you decide you do not need to see the waterfall during normal operation, you should at least familiarize yourself with it as there are real advantages to having it available at times. At the bottom of the waterfall display there are some user settings that might need adjusting, although the default settings are OK. The <Bins/Pixel> setting can be set to 5, and the <Start> can be set to 200 Hz. I like the <Blue3 Palette>, but that is a personal choice. You want <Flatten> checked, and <Spec> at 25% - these are suggested starting points, but feel free to adjust as needed, and changing settings will allow you to test them to see what works best for you. The only other setting I would suggest you make is to check the box on the main program window which says <Lock Tx=Rx>. This will ensure the two stay aligned, with the added benefit of when you click on the Waterfall your Sample QSO screen (Courtesy of the author) Tx/Rx frequency will both move as needed. There are times when you will want to select a calling frequency just above or just below a station to get out of a pile-up and increase the chances of being heard (bonus tip, no extra charge!). The waterfall allows the use of the mouse to click on a frequency/ area without having to type the change in manually, which is much faster, and sometimes speed is of the essence! The lower left part of the screen is where the band selection option resides, and if CAT is set up, the radio will tune to the band selected automatically. If manually entering the frequencies, the suggested frequency is shown in the drop-down menu next to each band option. Watch the top-left portion of the screen under Band Activity to see stations that have been decoded. Depending on when in the 60-second cycle you press the <Monitor> button, stations will either decode around the 50-second mark, or they will decode on the next cycle. See sample screen shot above. You will notice in the sample screenshot here there are multiple color highlights over various screen entries. Depending on the colors set in the <Colors> option settings, these indicate DX stations, CQ calling stations, and stations calling you (of course they can t call you unless they have heard you). Lines with no color highlight mean these are stations heard which are already in the middle of a contact. For the shortwave listener, a contact may be considered valid after IDs have been exchanged and signal reports have been traded as a minimum. Some stations will not log an entry until 73s have been successfully sent (the equivalent of saying Best Wishes or Good Luck) and signing off the contact. A tip for following along a contact s progression is to follow the Frequency listed next to the callsign you are tracking. Since there are many stations communicating at once, the frequency listing is a good way to quickly find the June 2017 The Spectrum Monitor 21

5 Left and right: JT9 and JT65 conversations. (Courtesy of the author) station you are following.) For an amateur operator, once a station is found calling CQ on the left panel (highlighted in green or pink depending on color settings), you have about 12 seconds to double click the call (or any part of the highlighted line), to initiate a contact. The program will auto-fill the <Generate Std Msgs> fields with the typical macros, and at the start of the next 1-min, cycle, transmit the first macro. This macro includes the other station s call sign, your call sign, and grid square. The next cycle will await a response, which, if it receives it, will answer back with their call and a signal report. This will show up highlighted in red (or whatever color you chose), and it will also appear under your message in the right pane titled <Rx Frequency>. After receiving this response, you once again have about 12 seconds to choose you next macro, typically <Tx3>, which sends their call, your call, and your signal report for them. They will send back a RRR message to affirm their reception of your report, and then you send <Tx5> which sends both calls and 73. The final return is the other station s 73. Above is a sample screenshot of a typical contact: EI7HDB calls CQ (Green); I respond (Yellow); he responds (Red); I respond (Yellow); he responds (Red); I respond (Yellow); six minutes total time for the contact. There are variations to this, depending on whether you or another station initiates the CQ call. If someone is answering your CQ, then you would send TX2 in response, then TX5 as shown in the above screen capture on the right. Here I called CQ; W6AER answered me with a grid square; I sent my reception report (Tx2); he sent his Roger and reception report; I sent my 73 (Tx5) and he responded in kind. I sometimes send as an alternative 73, RR TU 73 AK3Q which just fits the 13-character limit, including spaces. Others find creative ways to say thanks for the contact. Notice the log box that pops up at the end of a transmitted contact (when 73 is first sent by either party). You can simply click OK and the log entry is saved. The WSJT-X program has a built-in logger, and it also creates an import.adi file for importing into other log files such as N3FJP, DX-Labs logging program, or whatever logging program you use which accepts standard.adi files. For those interested in seeing where their signals are going (or seeing a map of stations you have heard) you can go to pskreporter.info and use the Map function. I ll talk about this more in a bit, but for now a screen shot will give you an idea of what you can expect (top of next page.) JT9 Mode JT9 is basically the same in terms of configuration and operation of the software, but it has a slight advantage in terms of having about a 2 db lower threshold over JT65. The bandwidth is significantly more narrow, and this allows a bit more power to be concentrated into a smaller signal. The area for operating JT9 is on the upper end of the bandwidth, above Though the slice of bandwidth is smaller for JT9, the narrow signal size allows more signals into a smaller space. The downside to this mode is a smaller number of people seem to be active on it, even though the WSJT-X program can allow both to run as we have seen. I presume some folks are limited in bandwidth by their radios, and others are simply running the JT65 mode by itself with this or other software. Because there are fewer folks on JT9, the band area is often open, and putting a call out here can often attract users to switch modes to work you (or a DX station to hear you calling them!). Additionally, that extra 2 db can sometimes make the difference between being heard and not being heard. So, give this mode a try as well just be sure to switch the mode to JT9 (and back again when finished) using the <Tx> box just left of the Macro message box. 22 The Spectrum Monitor June 2017

6 Power Levels The common refrain for many with weak signal modes runs something like this: I have worked all around the world with 5 watts on JT65 and JT9. Possible? Yes, no doubt. Likely during this period of reduced propagation and heightened solar disturbances? I think not at least based on my experiences. I am not a big gun with a 200-foot tower and stacked Yagis. I have a 20-meter wire dipole, and a multiband vertical antenna in a very compromised lot. I need significantly more power than 5 watts most of the time to make contacts. I find pretty normal, and 50 watts not all that unusual. Now, much of this depends on one s location, antennas, and local surroundings. One of the best aspects of the weak signal modes is the ability to work stations at greatly reduced power levels, and these are the perfect modes, along with CW and some of the other digital modes, to use with indoor or stealth antennas, or in situations where you want to make sure you do not cause interference to your neighbors. With watts I have worked some 50 countries in a relatively short time, including South Africa (3x), Finland, European Russia and Ukraine (both on 80 meters), Antarctica (2x), Bolivia, Dominica, Azores, Greece, New Zealand, New Caledonia, Australia (3x), Alaska (2x), North Cook Islands, Ecuador, Guadeloupe, Hawaii (2x), Uruguay and numerous other South American and European countries. I have also Worked All States on several bands, and even made contacts on bands I had never worked before such as 30, 60, and 160-meters. I say all of this not to brag, but to encourage the use of this software as another tool in the tool box for enjoying the hobby. 80-meter transmission shows reception across the US via PSKreporter.info (Courtesy of the author) digital mode designed primarily to check signal propagation around the world. The software has a log function, and there is the WSPRnet, similar to the PSKReporter site mentioned above. WSPR has been a very effective tool for using very low power signals, even into the milliwatt range, to probe possible propagation paths. The signals carry one s call sign, grid square, and power in dbm. Stations can be heard as low as -28 dbm! While not designed to be an actual communication mode, I just noticed today the ARRL s Logbook of the World (LOTW) has a category for WSPR in their forms, meaning it is an acceptable proof of contact like other standard loggings. I have used both WSPR and PSKReporter for checking both propagation and to see who is hearing me. I have been surprised more than once after checking these sites to see stations I was sure must not have heard my call did indeed receive me. Now, why they did not come back to me is another matter entirely... ha!! As a bonus, the WSPR software allows for band-hopping if the radio is CAT-controllable. What this means is the program can automatically check propagation conditions on various bands without having someone manually change bands. This is accomplished by coordinated hopping, where a number of stations around the world can move in sync to test propagation on each band. There is a scheduling function to choose which bands are of interest, and the user can supply a batch file/script to make necessary changes to the radio configuration as needed depending on antenna source and mode, etc. MSK144 WSPR Mode WSPR, or Weak Signal Propagation Reporter is a This is simply a mode you must try if you have six or two meter USB Tx/Rx capabilities. Just receiving the meteor scatter signals are fun, and if both sides of the contact show June 2017 The Spectrum Monitor 23

7 conceivably backscatter. Usually E-Skip conditions are tracked closely enough that a quick check of a propagation banner will let you know if skip is happening, and backscatter will be weak but stable signals with a hollow sound to them. As most backscatter happens in the HF range, there is little chance it will significantly affect signals in the VHF/UHF range. Echo Mode MSK144 screen shot. (Courtesy of the author) up, it is really special. Often there will be only one side received, but it is interesting to see how far away signals are being reflected from the ionized trails of the meteors. There are some differences in the panel and in the waterfall when working with MSK144, as the waterfall actually turns into a fast scan analyzer, showing the present and immediate past scan of the frequency range. I have shown a typical contact result in this MSK144 screen capture (above), as well as a common waterfall pattern for a reasonably strong signal at the beginning of this article. There is also an option on the panel for <Auto Seq> which is a very handy feature. When checked, the auto sequence feature allows me to double click on the station I wish to respond to, and it then automates the rest of the contact. This is nice because unlike the JT65 and similar modes, these contacts happen in 15 second bursts, and it can be a bit difficult to keep up. Another nice feature is if you are unable to complete the series of transfers, if the station comes back a bit later and a different contact has not been initiated, the program will go back into auto sync and complete the contact for you. This mode is suggested to be run at 100 watts or more with a Yagi, but I have had some small success simply using a base vertical antenna for six meters. There is no question one could follow a signal better with a Yagi by tracking it, but these contacts can be made with a simple vertical (the same is true for working the International Space Station). Use what you have! Keep an eye out for meteor shower reports as these can be great times to use this mode, but almost any morning or evening can have some meteor activity. There is always the possibility of picking up local stations antenna to antenna, but looking up the call signs will usually indicate distance, and this is a good indicator of scatter. The other propagation path, which could fool the software into making non-meteor scatter contacts, would be something like E-Skip or Echo mode is designed to allow you to make very sensitive measurements of your own EME signal even when they are too weak to be heard. To use this mode, aim your antenna at the moon, pick a clear frequency, and toggle <Tx Enable>. WSJT-X will then cycle through this loop every 6 seconds: - Transmit a 1500 Hz fixed tone for 2.3 s - Wait about 0.2 s for start of the return echo - Record the received signal for 2.3 s - Analyze, average, and display the results - Repeat from step 1 To make a sequence of echo tests: Select <Echo> from the Mode menu. - Check Doppler tracking and Constant frequency on the Moon on the Astronomical Data window. - Be sure that your rig control has been set up for Split Operation, using either Rig or Fake It on the Settings Radio tab. - Click <Enable Tx> on the main window to start a sequence of 6-second cycles. WSJT-X calculates and compensates for Doppler shift automatically. When proper Doppler corrections have been applied, your return echo should always appear at the center of the plot area on the Echo Graph window. Wrap-Up There are even more sub-modes available in this suite which are variations on the main programs, and the experimental modes for exploring various forms of scatter, and an experimental EME mode QRA64. Some of the experimental modes from the past have become the main-line programs of today, so the experimental modes included in this version of WSJT-X are worth a look. There is also much more to explore in terms of using these programs for serious antenna testing, propagation testing, and even transceiver testing. The powerful functions built into this software are nothing short of astounding, and in the months and years to come these programs will take even bigger strides toward understanding our world of radio signals. In a follow-up article, I will discuss in more depth how to use this software for testing antennas, receivers, and even for identifying RFI issues, so stayed tuned! T S M 24 The Spectrum Monitor June 2017