Dragonfly RX-666: Some Points to Consider

Having spent quite a few hours with the RX-666 over the weekend, I feel confident enough to come up with an evaluation of the receiver and its interaction with software. The link is here.

Dragonfly RX-666 - A New Player?

(Updated AUG-9 2020)

I have been playing with the new, China-manufactured RX-666 for quite a few hours the past couple of days. There has been quite a bit of interest in this device, especially since it claims to sample a whopping 32 MHz of bandwidth. I will do a write-up soon, but since questions are plentiful, I will outline some points of interest below.

1. The RX-666 is the brainchild of IK1XPV Oskar Steila and his project BBRF103. There is no controversy on this. The Chinese manufacturers (whoever they are) used his open-source project, which is completely legal. What surprises me (and him) is that they never let him know about it. 

2. It uses an LTC2208 ADC from Analog Devices. This is a 16-bit ADC. Some say it is the same that sits in the Excalibur G31/G33 etc. series. I can't confirm that. Oskar's original design used the LTC2217 ADC.

3. For VHF/UHF use, it uses the R820T2 tuner chip. It has capacity for 8, possibly 10 MHz, for instance for use on the FM band. The modified HDSDR exes are needed for sampling 2, 4 or 8 MHz. On the official HDSDR version, it will only sample 2 MHz. VHF/UHF will always start fully attenuated, leaving you to assume that there is no coverage.

4. Current sampling rate options are 32, 16, 8, 4, and 2 MHz. Alias-free ranges (limited by firmware filters) are 28.8, 14.4, 7.2, 3.6 and 1.8 MHz. Minimum LO setting is 1000 kHz with 2 MHz sampling. This means that with the current dll, minimum tuneable frequency is 100 kHz. No VLF reception yet. 

5. There is no LNA in the circuit, so sensitivity is a bit low. A good-quality preamplifier resolves this.

6. On an i5-6500 PC with 8 GB RAM, full sampling requires 30-55 % CPU. Recording 32 MHz to an external hard drive is more challenging, resulting in stutter. Playback of a 32-MHz file in SDR Console is ok.

Sampling 32 MHz with original BBRF103 dll and official HDSDR software

7. Software is available from the manufacturer in some sort - a version of HDSDR which does not seem to be original, an ExtIO dll and assosiated files, and Cypress drivers. Driver must likely be installed manually (I had to). No problems though.

8. The RX-666 will run from an official HDSDR installation. And more: It will run with the dlls that Oskar developed for his BBRF103 project.  I strongly recommend any RX-666 owners to use the original HDSDR software and the original BBRF103 dll files.

9. Temperature control: None except the box which is warm but not hot. Internal air temperature is around 40 Celsius after 6-7 hours with full sampling. Ambient is 23 Celsius.

10. DO NOT USE THE OPTIONAL 5VDC CONNECTOR!   You don't need it either.

QSL: Shetland Islands Broacasting Company 96.2 MHz FM

An excellent July 1 Es opening towards mostly Denmark and Sweden (192 logged stations) ended with  exceptionally strong signal levels from stations in Shetland and the Orkneys. SIBC had a good signal for about half an hour, with RDS decoding most of the time. An MP4 video with an "SIBC" jingle on was sent to the station. Shortly afterwards, I received a friendly response along with an e-QSL. SIBC shares the Bressay tower with BBC transmitters - at one time it seemed like it was the only transmitter location that was heard on my FM band. 1800 km.

Thanks Svenn M. for sharing v/s.

FM Logs For June 2020

June was a good month for FM DX up here. Most openings were to the south, meaning Russia, Belarus and the Baltic states with some stations from Poland, Germany, Sweden and Denmark too. The complete June log is available as a pdf file here.

A Mega Combo for FM DX

The short version: Use a wide-band SDR, HDSDR for surveillance and recording, and SDR Console for playback. And FMList for loggings!

As a Jaguar for Perseus user, I am used to being able to see (quite literally!) if there are potentially interesting signals on the MW band, both live and for the past minutes/hours/days if I’ve been away for some reason. Continuous or scheduled IQ recordings then make it possible to «go back in time» and log stations. This is a massive step forward compared to «linear» DX-ing and makes the DX hobby a lot more interesting. Why? Because you hear more stations! Of course, you can record IQ files at random for later analysis, but you must listen through them all to be sure not to miss anything. You do not have that much time. So, seeing potential DX is a vital part of the DX hobby in my view.

What about FM? There is no Jaguar software equivalent for FM. Es and Tropo conditions are much more random by nature than MW propagation. So, if you want to log FM stations, you need to be there when it happens, either by sitting in front of the radio yourself or rely on alerts from fellow DX-ers or FMList.org. Openings are easy to miss – you may have other things to do – and sometimes openings close, just to open up again half an hour later. And you were not there were you?

Enter HDSDR: See the stations

So, to keep on top of DX events, you need to see the signals. And you need to record them without knowing if there is anything interesting on the band. And there is a method to do so which in many ways resembles how Jaguar for Perseus works.

Fellow DX-er OJ Sagdahl and I learned recently about two documented, but to us unknown features in HDSDR: The combination of ‘Low Speed Waterfall’, and ‘Save Current RF Waterfall to Image File – Periodically’. Low Speed Waterfall enables you to slow down the waterfall, thus making it cover a longer time span. The Save Current Waterfall function will save the RF waterfall as a BMP image at intervals you set. Waterfall is far better than spectrum to detect signals, so I suggest you minimize the spectrum display as much as possible. To make the waterfall even bigger, you can collapse the mode section so that only the waterfall and spectrum (or what is left of it) are displayed (see image below). This combination enables you to check a day’s DX by using a minute to scan through your image files and see if anything interesting has happened. Make a note of which times are interesting to check. Then, play back the recordings you made.

If there is nothing of interest in the image files, you can delete the recordings you made (and the image files as well if you want to). This way, you keep hard drive consumption to a minimum.

HDSDR playing with mode section collapsed

Since HDSDR is connected to the SDR you use for scanning the waterfalls, you also need to use HDSDR to record the IQ files. This is straightforward. HDSDR has a good recording scheduler, it is super-easy to start an IQ (or RF in HDSDR terms) recording on the fly, and HDSDR lets you organize your IQ files in a logical matter. Such as one folder for every day. This makes recordings much easier to retrieve. Just be sure to select “PCM 16” instead of “Auto” for sampling rate, because “Auto” is 32-bit instead of 16-bit and your recordings will double in size for no purpose. And speaking of size - individual HDSDR files should be less than 4 GB. I use 3.8 myself.
There is however a better alternative when you want to play back your files.

Enter SDR Console: It’s playback time

Say you find half an hour of interest, you have made an IQ recording and you want to check it. The best option for playback is without a doubt SDR Console. For two reasons: First, Console has an excellent RDS decoder. Some say it is almost on par with the standalone RDS Spy. Second, Console playback is file size independent. Console collects all the files from a recording session to a single playback resource. With Console’s Analyser, you can jump to any minute in the recording, go back and forward in predefined time intervals, and it lets you create a playback loop so you can check a certain time span again and again. And most important, you don’t have to think about loading another file. An overnight HSDR session with dozens of IQ files is handled as one “file” by Console.

Console lets you create MP4 video files on the fly, for your personal archive, for bragging to fellow DX-ers or for reception reports.

RDS display (bottom left), playback analyser (top), file info (bottom centre)

Why use two programs?

Because HDSDR has properties Console hasn’t, and the other way around.

An added benefit from using one program to record and another to play back, is that you can continue to record IQ files while playing back recorded ones.

My own setup comprises three RSPdx from SDRPlay, connected to one PC each. Each of them samples 8 MHz to cover the entire FM band. The IQ recordings are routed to an external high-capacity hard drive connected to each PC. I use Seagate 2.5”, 4-TB drives. HDSDR can handle just about any good-quality SDR available (except newer RF Space and Winradio SDRs). SDR Console plays back HDSDR files extremely well.

FM List (fmlist.org)

FMList, together with MWList, DABList and TVList, is the brain child of Günter Lorenz, and is maintained by him and a large group of editors. It's arguably the best combined source for databases and logging stations on the planet. Using the database to log stations is exceptionally simple, and surely accounts for the large number of FM DX-ers, especially in Europe, who use this resource. It's not perfect in every aspect, but nothing else comes close for the FM DX-er.

Belarus FM QSLs

On June 22 I had a good Es opening to the south, with stations heard from Poland in the west to Moscow in the east.

Especially good signals came from Latvia and Belarus, and I added 15 new Belarus stations to my log. I prepared reception reports to three of them, Radio Relax 87.5, Yumor FM 93.7 and Avtoradio 88.2 MHz. Alex Yankovsky at LLC Vashe Televidenie kindly confirmed all of them. I also had Yumor FM on 91.9 MHz, but there are two of them on that frequency in Belarus, and the local weather update on the full hour was missed in signal loss. So, there was no definite ID on that one.

The distance was around 1860 km.

From Winter MW DX To Summer FM DX

I have lived, and DX-ed, under the assumption that FM DX-ing is a useless effort at my northerly location. However, two years ago following advice from fellow DX-ers I did a "test season" with my relatively new SDRPlay RSP1A, and a very old, 3-element FM antenna placed in the attic. While I only caught one proper Es opening, the result was staggering, with well over 200 stations logged in one afternoon/evening.

Last year I really didn't try much, and I think conditions in general were poor as well. For this season though, I had bought 3 RSPdx from SDRPlay, and an 8-element FM antenna from InnovAntennas. I had sold off my RFSpace CloudIQs and Airspy HF+ so I had some cash ready.

The FM antenna proved an immediate success. It was mounted outdoor on a 6-metre, Ø40 mm aluminium tube/mast and pointed in a southerly direction.

InnovAntennas 8-element FM antenna

I have set up the three RSPdx with three PCs, external 2.5", 4-GB hard drives and let them sample 8 MHz each, to cover the entire FM band. The connection from the antenna to the SDRs is via a 1:5 splitter/preamp from Cross Country Wireless. I monitor and record with HDSDR v. 2.80 since it's quite gentle on CPU and RAM consumption. Playback is done with SDR Console with its excellent RDS decoder.

First Es opening of the season happened on May 30. I will update the FM logs on a monthly basis, and the complete log for May is a good point to start. The most surprising bit for me was Faroe Islands. Not that it was heard, but 8 stations! Some with very low power.

If anyone want more frequent updates, the hangout place for FM DX-ers, especially in Europe, is FMList.org.

It is true though, that in the south, Es and Tropo conditions are much more common. And what's Tropo DX, or even local QRM for some, is Es DX for me. However, I think that northerly locations may have benefits of their own. Such as being able to hear regions that are difficult or maybe impossible to hear for DX-ers in the south. I have ordered another FM antenna from InnovAntennas, and I have some thoughts about where to aim it.

June loggings are due in a week. It will be a long list!

Extending The Arctic MW DX Season Into The Midnight Sun

May 15. At around 18:30 UTC, ABC Newsradio, Busselton WA 1152, with a readable signal. Distance: 13,396 km. On the following night, the sun did not set. Now, how is that for daytime reception?

Our beverages shouldn't even be up at this time of year. The thing is, I need to adjust antenna deployment to reindeer migration. Sounds exotic, doesn't it. Well, there is a logic behind this. The reindeer have their summer pastures at the coast. As autumn comes, they migrate to the inland winter pastures. Around August 25 or so, the area is "clear" for antenna deployment. For obvious reasons, I don't want the animals to have their antlers entangled in our wires. It's not good for the wires, and certainly not for the reindeer. One year, a lonely left-behinder I wasn't aware of got trapped in the 310 beverage wire. I managed to free the animal, though it was a bit scary since it was a full-grown oxen with impressive antlers!

When April arrives, the season is more or less over, and the beverages are reeled in, leaving the area safe for the original "inhabitants" to enter. However, the 80-degrees beverage was left standing this year, because of excessive snow levels on the path. Not much trouble for the reindeer though, they can jump over the visible parts of the wire.

This year, we started to monitor the beverage more closely than previous years since we heard good signals from Australia late in April So, for how long? As it turned out, for a very long time.

There is no sunset from May 16 onwards, and I was quite surprised to hear Adelaide-891 and Wagin (WA) 1296 in the end of April, when midnight was only civil twilight. Adelaide, and even other stations like 5AU on 1242, were heard on May 2. And the following days, until May 15 at least, stations from Western Australia were heard. And maybe we could have heard them even longer if conditioins were right. How could this be?

There are two reasons. First, and definitely most important: Mainland Asia, and especially China, are significantly attenuated at this time of the year. So, even a very weak signal can be copied. Secondly, there is greyline propagation from Australia almost all the way. Only the last few hundred km do the signal propagate through daylight, and then with the sun at a very low azimuth. And daylight reception of distant MW stations is nothing new in the Arctic. It is quite common to log North American stations in bright sunshine during autumn and spring here.

ABC Adelaide 891 at 18:30 UTC on May 5.

Interestingly, the signal from Adelaide crosses China with all their power houses which are not heard at all. As daytime increases, only the westernmost stations in Australia are audible. Such as 1152, 1269 and 1296.

In all fairness, this is not exciting DX, in that one could hope to hear new stations. Still, for us, it's a new barrier being broken. MW DX from 13,000+ km away, while in 24-hour daylight!

Post-Season Antenna Works

Well, "post-season" is a bit premature as today APR-12 I heard several North American stations on the 310 beverage with good signal levels; CJWI-1410, CHKT-1430, WMBD-1470, WGVU-1480, WLAC-1510 etc. And we hope that the two Asia beverages will still provide a week with good signals from Australia. But the most productive beverage, the dual, staggered 340 beverage, was taken down yesterday. After a six-week pause, both Covid-19 and weather related, I finally found a weather window to visit my Kongsfjord site on APR-11. A snow-packed entrance awaited me.

Snow shovel strategically placed outdoor!

March and April (so far) have been challenging months this year, weather-wise. Lots of snowfall, and lots of wind that packs the snow in certain areas and cleans the terrain in others. As luck would have it, the starting point of the easternmost wire is in the "packed" area. Though 150 cm high, the support was covered by another 75 cm of snow. It took quite a bit of shoveling, and not least find the correct spot to shovel! The end points were also covered - in ice! The rest of the wire was above the snow, and in excellent condition. So, after a 1h 45min exercise, 2 x 350 metres of wire had been reeled in.

340 starting point

I think next year I will attach a fiberglass mast to the pole so at least I know where to begin.

The other beverages were up and in good shape. But the 310 beverage starting point is buried in even more snow. It will likely come down the coming weekend, along with the 50 beverage. Happy days...

Next, I connected the standard KiwiSDR antennas to KongSDR and ArcticSDR. The 70-metre longwire and the NCi Megadipol were connected, and an outdoor connector failure for the Megadipol was repaired. The Kiwis are now back to their excellent SW reception. The Megadipol on ArcticSDR is superior for higher SW reception (12 MHz and up). KongSDR is a good alternative for lower SW and MW reception. DRM reception has been enabled. Kiwi users please observe that the Stats tab now has sunrise and sunset times available. Times of course UTC.

Sunrise and sunset times, thanks to Jari Perkiömäki.

To end this blogpost, the photo below was taken upon departure at 16 local. The clouds had finally given way to a very bright sunshine. The 100-km return trip was a breeze.

A Brief Summary of The 2019-2020 Season

In the early days of April, the MW season on 71 North is soon coming to an end. The days are already 15 hours long, and northern signal paths are becoming increasingly attenuated. So, maybe time for a little round-up!

On a personal level for the KONG crew, the season started in the worst possible way with the loss of a great friend and excellent DX-er, TJ Bråtveit. TJ was a part of the KONG crew for many years, and will always be missed. The remaining three of us, me, OJ Sagdahl and Ole Forr, will keep up the tradition, which includes two annual gettogethers at Smøla island, and two, including the main KONG DX-pedition, in Kongsfjord.

The Kongsfjord antenna line-up was similar to previous years; four beverage antennas. The dual, staggered beverage to the North American west coast proved exceptionally efficient this season, surely a result of feedline and grounding replacements. Throughout the season there was a steady flow of new California loggings - partly due to conditions but surely also due to "cheating" with daytime power. Our temporary, 1000-metre remote setup at Mount Loran also logged lots of nice stuff for us. It was probably the last autumn we were allowed to use that site. We'll see what to do the coming autumn. "We have a plan"!

One of the new logs this season.

The Pacific DX was.... I wouldn't call it disappointing, but... But yes it was. There were some interesting openings, especially towards Western Australia, but I don't think we ever spotted a truly great opening. Some new stations from Australia and New Zealand were logged though. Personally I got my first Tasmania station, but on x-band so not "really".

The three of us have our own PCs and SDRs running in Kongsfjord and Smøla, and activity levels between us vary quite a bit.  I am certainly the lazy bugger of the team but I did hear a few great stations myself, or with the help from the other two, which can be found in the logbook below. Most common stations omitted. Speaking of which: DX-ers have always shared loggings. Nowadays, the methods of sharing vary a lot more than in the days of paper-based publications. Things have become much more fragmented. My own logs are found in the HCDX Log and MWList.org. I am surprised to see though that many DX-ers these days never publish their logs anywhere - but are more than happy to publish their QSLs. I am somewhat at loss to the logic behind this.

Click here for Bjarne's log.

Weather this winter has been very challenging, much more so than usual. Windy, snowy, stormy. And no sign of spring as I write. Apart from one short outage, the new fiber connection has worked superbly though, even (although with reduced capacity) during a fiber breakage out at sea. Much better than the old 4G connection. Despite the dreadful weather, only one short power outage was noted. Thanks to clever internal power management, all equipment came up again except two KiwiSDRs which needed some extra help.

The beverage antennas will likely be dismantled during the Easter holiday, as the reindeer migration to summer pastures is underway.  I bought an 8-element FM antenna from InnovAntennas recently, and hopefully this summer too will see a few Es-openings. They are exceptionally few on this latitude, but intense! Three SDRPlay RSPdx should provide enough FM coverage.

For MW, the Perseus SDR continues to be our receiver of choice. There are two reasons: 1) The Jaguar software is developed especially for the Perseus. The integration is virtually seamless and Jaguar provides a massive improvement in efficiency over any other software for dedicated MW DX-ers. 2) The Perseus is still in many ways a benchmark SDR. You will find other SDRs with similar or even better specifications (such as the Winradio G33DDC). However, replacing the Perseus and porting Jaguar to a new platform would be a massive cost for many DX-ers. Still, what the future brings nobody knows.

And in late August, another KONG season starts again!