AmateurRadio.com

The other evening I was having a cup of tea and checking out my new QST that just arrived and found myself very interested in a piece written by Steve Ford in his column Eclectic Technology. The title caught my eye "When a signal is barely a WSPR" Steve looked at how the Raspberry Pi could be used for WSPR transmissions. Seeing I have the Raspberry Pi3 this sparked my interest. It was pointed out that all you need to turn your Pi into a WSPR transmitter is a board from TAPR called QRPi.  The board is offered at a very reasonable price of 29.00 U.S and it's set for 20m at 100mW. Before I got to excited about this little project  I wanted to see if using 100mW's would net me any results. I have seen other hams in the past net great results with far less than 100mW's and WSPR is known for it's great decode at very low power........BUT.......I do have a challenging setup here. On Friday late afternoon I gave WSPR a go on 20m at 100mW and was I impressed with the results. I was received by DK6UG for a distance of 39383 miles per watt and also ON7KO for a distance of 37285 miles per watt. I was amazed that my setup was able to produce those results! Now another question I wanted to consider is at 100mW how much of that actual power makes it to my antenna? To do this I referred to a coax calculator I punched in the type of coax (RG8X) the SWR (1.4:1) the length (30 feet)  the frequency (14) and finally the power (100mW) The calculated amount I was informed was 92mW of raw power! So this bumped my miles per watt to 42810 for DK6UG and 4053 for ON7KO! It's not timo look more into the TAPR project!!

2.5mH 136kHz loading coil at WH2XND

For the past few weeks, Ron, NI7J in Phoenix, has been activating his experimental station, WH2XND, in the LF band ... on 75.550kHz (WSPR), where he is licenced to operate.

Last night I decided to put my nightly 630m WSPR beacon on hold and have a listen for Ron's signal using my 10' x 20' loop.


Ron's main experimental operating has been on 630m and 2200m WSPR mode but his recent activity on 75kHz has sparked a lot of interest among dedicated summertime listeners. WH2XND is licenced for 10W ERP on 75kHz, not a number that's easy to muster considering the poor antenna efficiency produced by typical amateur installations ... however, judging from Ron's coils, his installation looks far from 'typical'!

Ron's signal is being well heard, even up in Alaska, in spite of the noisy summer conditions and it will be interesting to see how well it propagates once we move into the fall and quieter winter nights.

The big loop seemed to do well with Ron's signal last night, resulting in 55 decodes starting at around 2300 local time and continuing to sunrise.

Timestamp                    Call                   SNR         Grid  
  
2016-07-12 12:28      WH2XND            -28            DM33xt     
2016-07-12 12:20      WH2XND            -27            DM33xt     
2016-07-12 12:16      WH2XND            -25            DM33xt     
2016-07-12 12:12      WH2XND            -28            DM33xt     
2016-07-12 12:08      WH2XND            -27            DM33xt   
2016-07-12 12:04      WH2XND            -28            DM33xt     
2016-07-12 12:00      WH2XND            -29            DM33xt     
2016-07-12 11:40      WH2XND            -25            DM33xt     
2016-07-12 11:36      WH2XND            -20            DM33xt     
2016-07-12 11:32      WH2XND            -18            DM33xt     
2016-07-12 11:28      WH2XND            -18            DM33xt     
2016-07-12 11:24      WH2XND            -19            DM33xt     
2016-07-12 11:20      WH2XND            -19            DM33xt     
2016-07-12 11:16      WH2XND            -20            DM33xt
2016-07-12 11:12      WH2XND            -20            DM33xt     
2016-07-12 11:08      WH2XND            -19            DM33xt      
2016-07-12 11:04      WH2XND            -19            DM33xt      
2016-07-12 11:00      WH2XND            -20            DM33xt     
2016-07-12 10:56      WH2XND            -20            DM33xt      
2016-07-12 10:52      WH2XND            -21            DM33xt      
2016-07-12 10:48      WH2XND            -22            DM33xt      
2016-07-12 10:44      WH2XND            -23            DM33xt      
2016-07-12 10:40      WH2XND            -24            DM33xt      
2016-07-12 10:36      WH2XND            -25            DM33xt      
2016-07-12 10:32      WH2XND            -26            DM33xt      
2016-07-12 10:28      WH2XND            -24            DM33xt      
2016-07-12 10:24      WH2XND            -24            DM33xt      
2016-07-12 10:20      WH2XND            -25            DM33xt     
2016-07-12 10:16      WH2XND            -24            DM33xt     
2016-07-12 10:12      WH2XND            -23            DM33xt      
2016-07-12 10:08      WH2XND            -26            DM33xt      
2016-07-12 10:04      WH2XND            -25            DM33xt      
2016-07-12 10:00      WH2XND            -26            DM33xt      
2016-07-12 09:56      WH2XND            -26            DM33xt      
2016-07-12 09:52      WH2XND            -27            DM33xt      
2016-07-12 09:40      WH2XND            -26            DM33xt      
2016-07-12 09:36      WH2XND            -25            DM33xt     
2016-07-12 09:32      WH2XND            -24            DM33xt      
2016-07-12 09:28      WH2XND            -26            DM33xt      
2016-07-12 09:24      WH2XND            -26            DM33xt      
2016-07-12 09:20      WH2XND            -28            DM33xt      
2016-07-12 09:16      WH2XND            -27            DM33xt      
2016-07-12 09:08      WH2XND            -27            DM33xt      
2016-07-12 09:00      WH2XND            -27            DM33xt      
2016-07-12 08:56      WH2XND            -28            DM33xt      
2016-07-12 08:52      WH2XND            -29            DM33xt      
2016-07-12 08:44      WH2XND            -29            DM33xt      
2016-07-12 08:40      WH2XND            -27            DM33xt      
2016-07-12 08:36      WH2XND            -28            DM33xt      
2016-07-12 06:44      WH2XND            -32            DM33xt      
2016-07-12 06:32      WH2XND            -31            DM33xt      
2016-07-12 06:28      WH2XND            -31            DM33xt      
2016-07-12 06:24      WH2XND            -30            DM33xt      
2016-07-12 06:20      WH2XND            -30            DM33xt     
2016-07-12 06:12      WH2XND            -29            DM33xt      

His signal peaked here (shown in blue above) about an hour before sunrise, with almost a dozen decodes in the -18 to -20 region ... not far from audible CW levels which will probably be seen in winter. It was interesting to note as well, that in several transmitting sequences, Ron's signal was stronger in Alaska than it was here and in Washington state ... just the opposite of what one might expect.

In the past, I have had good results on 75kHz with Dex (W4DEX), when listening for his QRSS CW signal, using my normal inverted -L with a 2.5mH RFC inserted in series with the antenna's normal loading coil.

'XRS/5' on 75kHz from W4DEX in NC

If you can give a listen for Ron's WSPR signal and send him a report ... or better yet, upload your spots to the WSPRnet site, he would be very appreciative. For listening, set your receive frequency to .074kHz in the USB mode. The software will take care of the rest. You can upload 'LF' spots with your software by setting the '.074' receive frequency in the program's normal frequency or band window.

24 Hour 'JT' 6m Activity

For the past few weeks I've been able to transmit in the WSPR mode on 630m for the first time. For a long while I've tried to avoid it since the mode does not allow for two-way QSO's to be made. For that, excluding CW, one of the other weak-signal digital-modes such as JT-9 would need to be used. I've been using a new transverter sent to me for Beta testing ... hopefully I'll be able to report more if the unit receives final approval for production.

The transverter develops just over 70 watts output when run on 13V and so far, has been able to take all of the nightly punishment I've been able to throw at it with flying colors. Here is a WSPRnet screen shot taken from a typical night of my WSPR beaconing on 630m:

courtesy: KB5NJD's 630m Info

I was also able to have my first JT-9 mode QSO this week, with Toby, VE7CNF. This mode is the weak-signal WSPR QSO mode, tailored for LF/MF work and allows for calls, signal reports and confirmations (R's) to be exchanged ... the minimum requirements needed to claim a contact. Although additional information can be exchanged, its 13-letter message buffer does not exactly promote ragchew style conversations and some creativity is required to exchange more than the basics.

With many of our newer 'digital-savy' amateurs not necessarily being proficient in CW, I suspect that JT-9 may well evolve to become the go-to weak signal communication mode on 630m, much as it has in Europe. In fact, popularity of this mode in Europe has already spawned a few JT-9 contest weekends on 630m, with high activity levels being reported. I'm really looking forward to a 630m JT-9 QSO party in North America, once the band becomes a reality in the U.S.A.

JT-9 is capable of decoding signals reliably down to -24db SNR and boasts a 50% reliability of decoding at -26db SNR. Audible CW drops out at around -16 to -18db SNR, so communicating with JT-9 is the equivalent of going from 100 watts to around 800 watts ... a significant improvement and very helpful on 630m! Like WSPR, JT-9 will work with non-linear transverters and amplifiers such as the commonly-used and simple to build switching MOSFET Class D/E styles.

There also appears to be a fast-growing use of JT-65A on the 6m band this summer, with numerous 'CW forever' operators finding the mode's ability to dig up to 10db deeper into the noise paying off with surprising results. Some western North American operators have noticed that European JT-65A signal levels indicate that they should be in the CW-copiable range yet no CW activity is heard, for which there seems to be no ready explanation. Perhaps more will be learned this summer as the use of this mode continues to expand.

As one of the 'CW forever' proponents willing to try something different, I also have been listening for and working stations on 6m over the past few days on JT-65A. With the IC-756ProIII throttled back to 25 watts, I've found it fairly easy to make contacts when the band is open but have yet to hear or work anything unusual.

I'd love to hear your own comments on the use of JT-9 or JT-65A, particularly on 630m or on 6m ... maybe you can pass along some tips for those of us that are new to the mode on this band.

I may have to reconsider this 'CW forever' thing!

For those of you that are fans of the low-powered "party balloon" floaters, such as the recent S-9 flight by VE3KCL, now comes a different kind of floater and one that really does float ... on the Pacific Ocean!





The "Ocean Floater" is the work of Bob, ZL1RS, who has been very active in tracking the other floaters from his excellent receiving site down-under. Like the balloons, Bob's beacon also utilizes the QRP Labs U3S hardware to transmit data in both WSPR and JT9 modes. The little beacon runs ~100mw on the 30m WSPR band and tracking this one will likely be a bit more challenging than following the high-flying balloons.

Bob's 'Ocean Floater courtesy: http://www.qsl.net/zl1rs/oceanfloater.html

Here is Bob's description as he posted to Yahoo Groups QRP Labs:

A small project inspired by Hans' Voyager ideas at
http://www.hanssummers.com/voyager.html ... the Floater is a 100mW
transmitter on the 30m band with a short base-loaded whip antenna
mounted on a buoy that will drift in the Pacific Ocean. It is sending a
standard WSPR transmission once and hour, followed by two JT9
transmissions giving its position, the temperature, and the battery voltage.

The project was deliberately kept very simple. A QRP-Labs U3S
transmitter and firmware made the electronics side easy. The U3S was
rebuilt on a board with a more open layout to allow experimentation and
the addition of a PICAXE controller to switch things on/off as required
to reduce overall battery consumption. Most of the "hard work" was in
the buoy body and antenna. More information about how this went
together can be found at http://www.qsl.net/zl1rs/oceanfloater.html

Today the Floater left on the yacht Windflower to be released into the
south-west Pacific Ocean in a few days time. This will ensure the
Floater is well clear of the coastal currents around ZL that would
otherwise have 'beached' it along the coast if it been launched from the
shore. Unlike balloon flights, things will happen very very slowly, so
updates to the webpage and tracking map will probably only be made on a
daily basis. WSPRnet spots will show the 4 character Maidenhead
locator position, and the JT9 decodes have a 6 character Maidenhead
resolution. Any JT9 decodes you receive will be appreciated via e-mail
to [email protected]

73, Bob ZL1RS


The beacon will use the call "ZL1SIX" and will be launched shortly, near Minerva Reef. Watch Bob's website for tracking and updates and ... good luck Bob!

The past few weeks have seen many of the VK 630m WSPR stations making it into North America's west coast and points east. VK2DDI, VK2XGJ, VK3ELV and VK4YB have been the signals most often seen. Particularly dominant is the signal from Roger, VK4YB, the northern-most station, located in Moorina, Queensland, near the Pacific Ocean.



Roger's signal has been decoded locally by myself as well as VE7BDQ and VA7MM, creating excitement over the more normal nightly spots from the central states.

2016-04-13 11:10 VK4YB 0.475646 -28  QG62ku 5 VA7MM CN89og
2016-04-13 11:20 VK4YB 0.475647 -29  QG62ku 5 VA7MM CN89og
2016-04-13 11:28 VK4YB 0.475647 -28  QG62ku 5 VA7MM CN89og

2016-04-13 11:28 VK4YB 0.475644 -23  QG62ku 5 VE7BDQ CN89la
2016-04-13 11:36 VK4YB 0.475644 -26  QG62ku 5 VE7BDQ CN89la
2016-04-13 11:52 VK4YB 0.475643 -25  QG62ku 5 VE7BDQCN89la 
2016-04-13 11:56 VK4YB 0.475643 -28  QG62ku 5 VE7BDQ CN89la

2016-04-07 08:54 VK4YB 0.475643 -25  QG62ku 5 VE7SL CN88iu
2016-04-07 09:36 VK4YB 0.475644 -29  QG62ku 5 VE7SL CN88iu
2016-04-07 10:08 VK4YB 0.475644 -29  QG62ku 5 VE7SL CN88iu
2016-04-07 10:18 VK4YB 0.475644 -29  QG62ku 5 VE7SL CN88iu
2016-04-07 11:04 VK4YB 0.475644 -29  QG62ku 5 VE7SL CN88iu
2016-04-13 11:06 VK4YB 0.475644 -24  QG62ku 5 VE7SL CN88iu
2016-04-13 11:10 VK4YB 0.475644 -23  QG62ku 5 VE7SL CN88iu
2016-04-13 11:20 VK4YB 0.475644 -23  QG62ku 5 VE7SL CN88iu
2016-04-13 11:28 VK4YB 0.475644 -28  QG62ku 5 VE7SL CN88iu
2016-04-13 11:32 VK4YB 0.475644 -25  QG62ku 5 VE7SL CN88iu
2016-04-13 11:52 VK4YB 0.475643 -18  QG62ku 5 VE7SL CN88iu
2016-04-13 11:56 VK4YB 0.475643 -22  QG62ku 5 VE7SL CN88iu
2016-04-13 12:16 VK4YB 0.475643 -27  QG62ku 5 VE7SL CN88iu
2016-04-13 12:28 VK4YB 0.475643 -26  QG62ku 5 VE7SL CN88iu
2016-04-13 12:32 VK4YB 0.475643 -25  QG62ku 5 VE7SL CN88iu
2016-04-13 12:54 VK4YB 0.475644 -24  QG62ku 5 VE7SL CN88iu
2016-04-13 12:58 VK4YB 0.475643 -24  QG62ku 5 VE7SL CN88iu
2016-04-13 13:10 VK4YB 0.475643 -25  QG62ku 5 VE7SL CN88iu
2016-04-13 13:24 VK4YB 0.475643 -27  QG62ku 5 VE7SL CN88iu
2016-04-13 13:28 VK4YB 0.475643 -27  QG62ku 5 VE7SL CN88iu

Roger has sent the following information to me regarding his well-planned system:

Today's Sun courtesy: http://sdo.gsfc.nasa.gov/

With the sun remaining reasonably quiet over the past several days, a sudden spike in the geomagnetic field on Saturday afternoon saw a number of trans-Pacific spots showing up on 630m WSPR mode.

courtesy: http://wdc.kugi.kyoto-u.ac.jp/

In the predawn hours of Sunday morning, my own system decoded the VK3ELV WSPR beacon, located in south east Australia, 12,992 km from here. From an e-mail exchange, it seems that VK3ELV is using a 'drifting' IC706M2G on 10Mhz with a VK3XDK Transverter into an old HF AMP (2x 2SC2290) modified for 630m. This is running about 130-140 watts output. The antenna is an inverted L about 30 metres high and 1/4 wave long.

courtesy: https://www.google.ca/maps

VK3ELV 630m

Further to my south, the WG2XGP WSPR beacon run by Larry, W7IUV in central Washington, was reported down under by two different VK's on Sunday morning as well ... VK4YB and VK2DDI, both some distance from VK3ELV.

courtesy: https://www.google.ca/maps

It's interesting to note the time difference for these receptions, with Larry's reception being several hours earlier than my own (1304Z), close to my sunrise. As well, the 'spotlight' effect of propagation over such a vast distance is somewhat intriguing. I would have thought that if I should see any VK's on 630m, it would be the closer ones and not the further one, yet it was just the opposite.

Although VK3ELV's signal was right at the edge of WSPR decoding levels (-29db), it would only take a few more db to allow a two-way JT9 digital mode QSO to take place ... maybe something that will be possible in the coming years of solar minimum and much better LF/MF propagation. To be readable on CW would need an equivalent true power output increase of at least 16 times, requiring VK3ELV to run around 2,000 watts output!

Over the years I have seen ZL6QH a number of times on 2200m (QRSS CW mode) but this is my first reception of VK and, hopefully, not my last.

To keep up to date with overnight activities on 630m, visit the excellent site of KB5NJD. John posts a detailed daily summary of events. In addition, you will find some excellent resources to help you get involved in this part of the spectrum ... and remember, you don't need a big backyard or a big antenna to have fun on 630m.