What happens when: Multiple DMR signals & SDRangel

The below video shows native DMR decoding with SDRangel software. On 427.505 MHz is an OpenSpot V1 and on 427.565 MHz is a duplex "China" Spot. 

It is very easy to leave the SDR, in this case the inexpensive NooElec Nano3 tuned to 427.565 and then toggle in the channel down to 427.505 MHz.  Both hotspots were tuned to the same talk group of 31630 during the Tuesday evening Northstar Digital Net.

One thing to notice is that the carrier time keys up quicker and also "hangs" when a discussion drops compared to the quicker times on the duplex "China" Spot.

With SDRangel, you can "run" multiple decoders for different (or the same modes) at the same time. 

You would leave SDRangel "tuned" to one frequency and you can then tune up or down from that frequency in each decoder. This will work within the SDR's capable bandwidth. In the case of the NooElec Nano3, this is 2.8 MHz. 

Also, you can "run" multiple decoders (Analog FM Narrow, DSD for digital voice, Channel Analyzer, etc) all at the same time on the same frequency to just "hear" for example the buzzzz sound of DMR via the analog FM Narrow decoder PLUS the actual DMR demodulated audio AT the same time.

There is A LOT of capability with SDRangel. Give it a try. You will like it and the ability to customize the layout to your liking for certain tasks.

Rumble: SDR# Versus SDRangel

The new "Community Plugin" option by Rodrigo Perez of SDR Chile for SDR# allows near automatic installation of more than 27 optional plug in functions to the popular software defined radio application offered by Airspy.

Upgrading versions of SDR# is now much easier for those like me who customize this software with  helpful tools such as CTCSS decoders, recording tools, signal analysis and so much more....

While all  plugins will not be useful to everyone, this does make SDR# seem fresh and able to compete with SDRangel, my favorite SDR software for off the shelf, ready to go multi purpose wireless signal exploration. Lets compare the two!

SDR# 1713+Community Package to SDRangel v4.11.9

Only very recently did Edouard F4EXB reintroduce compiled Microsoft Windows to make the use of his fantastic SDRangel software.

Attempting to compare the two is very hard, so will start with comparing the 27 plugins first against features of applicable SDRangel functions.

Lets start out with a few of the stand out plugin options that are exclusive to SDR# compared to SDRangel.

• Plugin Calico CAT - Used for controlling radios such as the Kenwood TS-2000 

• Plugin DDE Tracker - Dynamic Data Exchange. For those interested in scheduling activity related to tracking satellites such as weather imaging NOAA 16, 17, 19, 20. 

• Plugin File Player - Provides the ability to play different audio or baseband files in SDR#

• Plugin Frequency Scanner  - Offers ability to save and scan frequencies in a list

• Plugin Gpredict Connector - Helps control satellite tracking equipment such as Az/El rotators

• Plugin IF Recorder - Records intermediate frequency signals

• Plugin Meteor Demodulator - Decodes Russian weather satellites

• Plugin MPX Output - Useful for streaming FM broadcast audio with RDS signals

• Plugin SDRSharp Net Remote -  Allows remote access and control of SDR#

• Plugin Time Shift - Save and replay spectrum almost like a Slingbox or VCR

What is actually missing from the larger list is more detail about decoding digital voice modes such as DMR, TETRA, D-Star, Fusion/C4FM, NXDN and P25.

While the SDR# Community Plugin does add in DSD+ functionality and Tetra decoding, it is not as straight forward to use compared to SDRangel's implementation of DSD. SDRangel also adds in FreeDV and a LoRa decoder as additional "channels".

SDR# through the television plugin allows the viewing of PAL, SECAM and NTSC analog signals, whereas SDRangel only allows PAL and SECAM but also adds DATV for amateur TV enthusiasts.  These are the older analog television protocols no longer in use, so will not enable the reception of newer digital broadcast television directly with an SDR.

Final Verdict

In summary,  SDR# along with the plugin additions may create better feature sets for those interested in certain recording and signal analysis features plus better satellite related decoding or ground station control.  SDRangel does not offer any of this, but does provide some basic recording and signal analysis.

Both pieces of software really can not be easily compared since they do many things better than the other.  The big point to make is that between both pieces of software, you have almost everything one could need that appeals to a modern radio hobbyist not just looking to monitor typical amateur radio or shortwave activities which SDRuno or SDR-Console seem to appeal towards more easily.

Hopefully this article encourages further experimentation with SDR# if you have forgotten about it or have yet to try SDRangel.

International Space Station to be visible on Sept. 19-20

The International Space Station to be visible on Sept. 19-20. The key word being "visible" and is not the only time you can see the ISS though.

Radio amateurs can listen via wireless during most passes with the hope to either listen in during a scheduled astronaut contact with a school or to use the digital packet relay system known as a "digi-peater" to bounce short text messages through the ISS and back down to Earth.


Non-Visual Voice Communication

The astronauts do not have much time for casual amateur radio operation, but you might be lucky if you give the station a call on 144.490 MHz in North America or 145.200 MHz elsewhere in the world. You will need to listen to 145.800 MHz for transmissions from the Astronauts.

Using different receive and transmit frequencies is known as split operation.  Astronauts have the ISS radio programmed the opposite was as you would on Earth.   The reason for this is to minimize interference and increased reliability.

The below photo is of a post card confirming a contact with the ISS and a local amateur radio operator.  The "QSL" card was sent from a ground station on Earth and was not dropped 220 Miles above from the ISS, if you were wondering.

Non-Visual Data Communication

If you are interested in non-voice communication, tuning in to 145.825 MHz will allow you to receive APRS data through the ISS.  Your AX.25 capable radio will use the same frequency on transmit and receive.  A path of "ARISS" will help ensure your transmission is received by the ISS and passed back down to Earth automatically.


Viewing the ISS

Applications such as "ISS Detector" for Android smartphones, tablets and Chromebooks work great to "predict" when the next pass will come over your area.  Apple device users may use "ISS Spotter".  Many computer programs also exist such as "Orbitron" for Windows users,  "Gpredict" for multiple platforms and "Nova" as being the three most popular or easy to use options.

There are also additional augmented reality and web based tracking tools available that are easy to find.

It is best to adjust your eyesight to the dark for at least 10-15 minutes before looking at the night sky. This gives your eyes some time to adjust for maximum viewing benefit.

On September 19th, the pass coming over the Eastern United States will track from South to North

The following day at just about the same time will see the ISS pass over yet again, but just lower in the sky compared to the night before.

Beyond visual observation, it would also be good to keep an eye on the APRS activity via the APRS.fi website to see if radio amateurs are "bouncing" signals from the space station.

You can track the space station and APRS activity via the RS0ISS call sign which broadcasts from the Russian module of the ISS. It is not always active though.  The best way to confirm recent activity is by looking at the AMSAT satellite status page or by looking at the very active Facebook group focused on the International Space Station A.R.I.S.S experiments.

If anyone would like to take some pictures of the upcoming ISS pass, it would be great if they can be shared in the comments or emailed to info@hvdn.org for a future article.

FCC Approved? Anytone D578UVIII

As of August 29th 2019, the long awaited Anytone Anytone D578UVIII has finally received its FCC approval.  What does this mean?   Expect this US tri-band DMR radio to be for sale, very, very soon.


T4K:  Its what you need

Every legitimate vendor who sells electronics capable of sending or receiving wireless signals requires an FCC ID per device.  Each vendor has a grantee code in order to identify themselves. In the case of Anytone, which is better known to the United States government as Qixiang Electron Science& Technology Co., Ltd, they are issued the code of T4K.

If you are interested in searching the FCC OET ID database, you can use either Qixiang Electron Science& Technology Co., Ltd, or T4K.  If you try "Anytone", you will not find anything.

Anytone D578UVIII  FCC ID Details

Now that you can go and find details on your own, you can visit https://www.fcc.gov/oet/ea/fccid to look at things such as an advance copy of the user manual and various photos and documents required for certification needs. As already reported, the US version would be capable of 2m, 1.25m and 70cm operation along with Bluetooth.

Anything else new learned?

Near all vendors of amateur radio equipment are taking pre-orders for the Anytone D578UVIII, so anyone who has already paid $35 to $50 USD should expect an update on actual shipping soon. Part of the real delay has been some FCC compliance issues for "out of band" operation which has just gone into affect and caused certain vendors to rethink how to sell radios in the United States market.

This ruling change actually creates a better radio experience for us amateurs who want to ensure no outside interference from commercial frequencies just above or below our licensed spectrum.

38 Pages: That is all?

Most every recent radio of Chinese origin continues to include no good printed instruction manual since the software changes often and would require massive rewrites. Most people will program the radio via computer software and the end user community generally decides to write copious amounts of user guides to help people use new equipment.  Our own collective efforts would likely be much better than the manufacturer could produce.

Beyond confirming cross band repeat and a speaker microphone with built in speaker is standard, much everything else was already known details. Cross-band digital repeat seems an interesting trick too.

For users of the BTECH 6x2,  Alindo DJ-MD5TGP or Anytone AT-D878,  this new mobile radio should be easy to use. Further updates to follow once HVDN members start to receive shipment of this new radio.

Download preliminary Anytone AT-D578UVIII Manual

Access Anytone AT-D578UVIII Facebook User Group

Pro Tip: Finding DMR Activity

As more and more users of digital voice amateur radio shift towards hot spot devices instead of local repeaters, it gets hard to find where people in your area are using DMR.

Since hotspots have such limited range, you would not likely be able to hear them "over the air" and there is not really any way to simply "scan the band" looking for activity like one may do on 2m or 80m.  So, how do you find DMR activity?

DMR: Get Predictive

Is this suggestion cheating? Not really.  There is a way you can use one of the many somewhat hidden analytic tools to find out what talk groups are most active and when.  This will help you learn when and where to spend time "lurking" since there are 1,439 officially set aside talk groups according to this nice Pi-Star DMR BrandMeister Talk Group page.

Using talk group 31630 (STEM) as an example, the chart below is predictive in the sense that every Tuesday evening at 20:00 hours Eastern US time, is a big spike of activity for a little over an hour. This is when the Northstar Digital Net takes place.

Another example on when you may find activity if you are traveling in the state of Louisiana is shown below by looking at talk group 3122.

How about if you want to feel really special and have "Nationwide US" all to your self with fewer people constantly asking for a radio check or signal report?   06:00 AM Eastern US may just be the time for you to sit on talk group 3100.

Where do you get these charts?

Here is where to go and find some possibly interesting talk groups and times to see what sort of activity is taking place.  https://brandmeister.network/?page=callstats

And now you know how to find the best of the best on DMR. 

Alinco DJ-MD5TGP: Upgrade Vocoder Process

It has been widely confirmed that the Alinco DJ-MD5TGP,  BTECH 6X2 and Anytone AT-D878 are essentially the same reference design and only have a few differences in hardware or software.

As discovered by Jason Reilly and his excellent page regarding the Anytone 868 and 878, it is possible for the user to change the vocoder.  This is done via software and is detailed here.

Alinco DJ-MD5TGP Baseband

HVDN was the first to point out that it was possible to expand the frequency range of the Alinco MD-MD5TGP.  The procedure for that was not far different than that of the Anytone, so upgrading the vocoder followed the same procedure with just a few differences.  Proceed at your own risk in doing this upgrade.

In our "Teardown: Expanded Alinco DJ-MD5TGP Review" article in November 2018, we pointed out the SICOMM SCT3258 chip and this is where the magic vocoder resides.

Go ahead and download this file from Jason's Tiny Upload link for the Anytone 878.  You can follow his instructions closely, but for the Alinco DJ-MD5TGP you will need to:

• Hold down # and PTT while turning the radio on to enter boot mode for SCT

• In the SICOMM software, you need to set the speed to 115200, not 9600 baud.

The Alinco DJ-MD5TGP used for this test already had version V2.01.05NJ. It was simple to upgrade to V2.01.07BA.  The receive audio seems to be even more pleasant now on DMR and preliminary audio reports seem positive, but more testing needs to be done.

Thank you Jason for all your great documentation!

More about the Alinco MD-5TGP via HVDN:

• Teardown: Expanded Alinco DJ-MD5TGP Review

• Review: Alinco DJ-MD5T Series DMR Radio

• FLASH NEWS!: Alinco MD-5 Series Cleared by FCC

• The Official "NOT" Review of the Alinco MD-5 Series

• Frequency Expansion: Alinco DJ-MD5TGP

• October 2018 Global Digital Repeater Round Up

More SDRangel goodness: FreeDV demod added & much more

Sorry, I need to stop being such a fan of SDRangel, but new features continue to roll out worth talking about.

Latest being the better ability to decode FreeDV, which is an open source digital voice mode suitable for use on the HF amateur spectrum allocations.

This voice mode permits FM quality audio in a 1.25 KHz wide channel with no tell tale "hiss" sounds as found while using SSB.   FreeDV outperforms SSB at low SNR.  If this all makes sense to you so far, this should be exciting.   If this does not make sense, the reason why this is important is that lower SNR means better quality audio can be received at lower signal levels, which means overall better performance, range and experience.

If you are involved in transmit capable software defined radio stuff, this latest feature on SDRangel is going to be interesting, along with the already native DMR, Fusion, NXDN, D-Star decoding capability plus DATV reception and transmission for those not just looking for voice modes. No other SDR software has this range of features.

FreeDV was built by an international team of radio amateurs working together on coding, design, user interface and testing. FreeDV is open source software, released under the GNU Lesser Public License version 2.1. The modems and Codec 2 speech codec used in FreeDV are also open source.

Now back to SDRangel v4.11.8

As mentioned back in July 2019, its is now very easy to use SDRangel. A Microsoft Windows executable is now not only compiled, but installable as any other application which makes installation very easy. Linux is still the better operating environment, but there is literally no major difference now with performance on either operating system family now.

You will still need a modern computer to run SDRangel though, which means 64 bit and not 32 bit Windows XP, Vista and earlier, so time to upgrade your computer. You could even run SDRangel on a Raspberry Pi if you really wanted, but that is not the goal of this article.

Here is the latest version you need to download: https://github.com/f4exb/sdrangel/releases/tag/v4.11.8

GD77: The first HT based Pi-Star hot spot

As mentioned here in the past, Roger Clarke is the wizard down under. He is known for his Git repository making the firmware upgrade procedure on MMDVM boards pretty painless and also his work surrounding an open source CPS for the GD-77 DMR radio.

For much of the summer, he has been working with Kai on turning the Radioddity GD-77 into a hot spot which is probably the most exciting thing I have come across recently.  This is such an amazing case of open source software at work and making closed hardware, much more open.

Head on over for a read on Roger's blog for much greater detail and get ready for some fun. My biggest questions are:

• Will this work with the Baofeng DM-1801 and other ODM variant radios?

• How will this impact the "hotspot" market and prices?

• Will other radios see similar innovation (Alinco MD-5TGP, Anytone 878, etc)

Continued Reading:

• GD-77 Hot Spot Mode

• GD-77 Community CPS

• GD-77 Frequency Expansion

• GD-77 Introduction to new CPS

• Improving the TCXO for Duplex Hotspots

Special Event: K1A Live From The 53rd Annual Mid-Hudson R/C Jamboree & History of Flight Air Show

The Mid-Hudson Radio-Control Society will host the 53rd Annual R/C Jamboree September 6, 7 and 8. See well over 100 giant-scale radio control models of vintage aircraft flying all weekend from 8:00 AM to 2:00 PM. 

The event is taking place at the Old Rhinebeck Aerodrome which is home to many vintage aircraft, including a flying reproduction of the Spirit of St. Louis.

The Aerodrome’s full-scale airshows will take place as usual on Saturday and Sunday from 2:00 PM to 4:00 PM, but the morning will host a special event amateur radio station operating under call sign K1A thanks to our friends over at the Overlook Mountain Amateur Radio Club.

The K1A station will be making contact via the HF bands as well as via internet assisted digital voice. Details are as follows:

HF Voice (USB mode)

• 21.300
• 14.230 
• 7.220 

DMR

• Brandmeister Talk Group 31630,

Echolink

• N2HVD-R

All-Star 

• Node 48878

Local Repeater

• 146.805 (-0.6 shift, 103.5 Hz PL)

There will also be demonstrations involving digital text modes such as PSK31 on the 20m band.

Aviation enthusiasts from around the world may be on hand via DMR to talk with too thanks to the STEM talk group and the excellent convergence opportunity between the various hobbies involved it creates.

A generous $5 dollar discount is available to anyone holding an amateur radio license who would like to attend the event.  The address for the event is at 9 Norton Rd Rhinebeck, New York