7 Year Itch: Global Digital Repeater Growth

With cooler weather here to stay for a while, its time for another global digital repeater roundup brought to you by Steve K2GOG of Hudson Valley Digital Network.

This has been a 7 year in the making project tracking the different digital voice modes currently leading VHF/UHF repeater deployments, according to data from repeaterbook.com

Every May and October, data has been collected from the leading source of the most accurate source for repeater details globally.  While some local options might exist that may be more up to date, ideally that information should be shared with repeaterbook.com to help out lazy travelers or those visiting an area for the first time who would more easily find this website compared to local club or individual websites.

Leaders:  Most Popular Options

By now, its defacto information that both the proprietary Yaesu Fusion and the quasi open standard multivendor DMR options are by far the most popular.   Low cost equipment helps drive the reasons which justify having more repeaters for these modes.

In the last year, there have been no major developments for new mobile or handheld equipment aside from some small refreshes on existing models like the popular Anytone or Alinco DMR radios. Yaesu has only given us the FT-5DR and FTM-200DR which is pretty good considering they are the only company that makes fusion capable radios which can be used on its 3200+ strong network of repeaters.

P25 is a commercial standard and is not marketed directly to amateur radio operators in any off the shelf non-professional grade equipment, but its growth rate is very strong. Based on how long it took for D-Star by Icom to become popular before flattening out, could we see P25 or NXDN become the dominant force in digital modes?   The answer is likely not, but that is where a new mode called M17 will come into play.

More then digital voice:  M17

All the digital modes mentioned all can do some other tricks beyond just voice communications.  Icom D-Star probably has the most advanced options from sharing location, photo, text and more with other users who have Icom equipment or the no longer made Kenwood TH-D74.

Yaesu Fusion really misses the mark to some degree, but most Fusion radios support analog APRS which increases interoperability for certain use cases.  There are a few DMR radios with very basic analog and digital APRS functions.

M17 which is absent for now on the digital repeater list promises us a true open digital standard for voice with some additional tricks up its sleave such as location sharing or text messaging.

The what's next

This would be a complex opinion based discussion, so lets use the airwaves or social media to discuss this fun stuff instead. Doink! 

HOPE: Global Digital Repeater Round Up 2022

 

Life has been busy for Steve K2GOG and that is reflected in the lack of recent blog entries on HVDN Notebook.  This post "should" have happened in late May or early June, but that was not possible due to 1,000 other distractions such as our Hudson River Radio Relay on June 11th, ARRL Field Day on June 25/26, a new job, countless family adventures and other stuff..

However, lets get things back on track here since it has now been five years since HVDN began and this is an appropriate way to re-energize with HVDN readers via our twice a year global digital repeater roundup series. Look for more stuff coming soon plus BIG news regarding HVDN if you live in the Hudson Valley of New York.

First off, let me apologize for having to use July 10th 2022 data to provide the 1H22 reporting data.

This extra month plus a few extra days should not really throw anything too far off, since its still clear that the total global digital repeater mode leader in volume is DMR. However, P25 is the true leader if we look at overall CAGR.

As noted in the table above, data is shown from May of 2018 and through July of 2022.  Measurements are taken every end of May and end of October.  Raw data per mode is shown for each period and CAGR was calculated for the May and October periods independently. An average of both periods can be found at the far right of the table.

The below table shows the included 2016 data if you were wondering how long we have been tracking things if you are a new reader and missed the past nine other articles. 

Report:  What has happened in digital voice since October 2021?

Well this is rather interesting to say the least. In our October 2021 edition, I predicted some growth projections as found in "SPECIAL EDITION: 10,000+ Digital Repeaters - October 2021 Global Digital Repeater Roundup" and I was not "too" wrong.  

Estimates I predicted last October for May of 2022 included:

• Yaesu Fusion Global Repeaters = 3135 forecast (Actual 3218)

• Icom D-Star Global Repeaters = 2429 forecast (Actual 2471)

• DMR Global Repeaters = 4009 forecast (Actual 2003)

• P25 Global Repeaters = 569 forecast (Actual 630)

• NXDN Global Repeaters = 160 forecast (Actual 167)

Lets first talk about Yaesu Fusion's latest developments.  My guess is that the latest crop of radios which have come to market over the last 8-9 months may have pushed some clubs or repeater trustees to put up some additional repeaters to support the people who paid money for digital technology. 

A few radios like the mobile FTM-300DR and FTM-200DR plus FT-5DR handheld added to an existing pool of equipment available with C4FM capability.  The strategy of "Make more Fusion radios" is probably working well for Yaesu as a single vendor ecosystem.  Go Yaesu! You blew past my forecast!

Yaesu FTM-200DR pictured which retails for around $380 USD
and is competitive against other digital mode offerings for competition modes

Oh, sad sad Icom.  Will you figure things out when it comes to D-Star? To your credit, I was surprised just a little as I had expected that you would lose repeaters according to repeaterbook.com but you did actually gain a few. 

Now I am not sure if all 2471 around the world are actually active and if repeaterbook.com removes incorrect data as frequently as they should.  I do know that when traveling not every D-Star repeater is on the air though....so your secret is safe with me for now.

Maybe people who now have the super fun Icom IC-705 and IC-9700 have put pressure on magical repeater gnomes to conjure up a few more repeaters to use those expensive radios on or the new handheld ID-52 which finally is shipping. Maybe this is true, but CAGR still does not lie.  

Hovering around 1% CAGR is not fun to see, but perhaps if some cost effective equipment that supports D-Star ever comes to market, that should change things like we see with Fusion and DMR.

Be honest, did you buy a $1700+ Icom IC-9700 radio to talk on your local repeater?
If yes, I would love to hear about that

Ok, now for the record, I currently own more D-Star capable radios than I do for DMR. However, DMR is the mode I use the most still when I have time to play radio.  

The Alinco DJ-MD5XTG continues to be my favorite "ham" grade DMR radio and I sort of wish something more expensive and with features like the D-Star Kenwood TH-D74 or Yaesu FT-5DR would come to market. The RFinder B1 is a really cool radio which supports DMR but I am not interested in a smartphone based device for $1000 USD.  

With continued impressive repeater growth numbers for DMR, most people probably are using Anytone or Alinco equipment plus who ever is still supporting TYT and Radioddity based equipment.  The key thing here is that lower cost gear gave DMR a boost and repeater ninjas knew what to invest in.

For DMR, there is even a rather good  Under $30 basic radio called the COTRE CO01D which only can program 16 channels, but otherwise is great to use with a hotspot on limited talk groups. It is doubtful we will ever see a competing D-Star option at this price since the JARL license for D-Star is 2-3x the cost of just one of these radios. 

Alinco offers the MD520 which offers dual band 2m/70cm plus 220 MHz and VHF air receive. Anytone has a comparable D578UVIII for sale at around the same price. Both compete with the Fusion radios for close to the same price.

I was really close to my P25 prediction and was only off by 1. That is actually pretty nice.. Growth of P25 is fueled by surplus commercial equipment. NXDN is pretty much the same story and actual versus predicted growth from October 2021 to today  Not much really to talk about for equipment since options for new gear are from commercial companies only and surplus options are too varied to discuss.

The growth of P25 is interesting to continue to see though. As more municipalities change radio systems around, it should be interesting to see how P25 and NXDN evolve within amateur radio.

M17:  Will it happen ever?

Being nice here, but I own 3 total M17 T-shirts, a bunch of stickers and a semi-functional TYT MD-380 converted to be used via hotspot for this open source FDMA based mode.   I have yet to find people local to me to try simplex M17 to M17 but have done that at a hamfest.  

Every day that goes by  possibly gets us closer to off the shelf turn key equipment for M17 and I am hopeful that this mode explodes once it has some reliable equipment to support it. The back end infrastructure to connect repeaters to is already in place and a few "test" repeaters are sort of available to a few people. 

To help keep M17 top of mind,  presentations can be found all over the place and the upcoming HOPE conference will feature at least two of them talking about this open source mode. 

Feel free to check out open source RF experimentation at 10:00 AM Saturday July 23rd co-presented by Steve K2GOG and Joe NE2Z plus a much more legit one about M17 scheduled along with so many great ones found at https://scheduler.hope.net/new-hope/schedule/# 

HOPE 2022 is going to be epic and hope you can make it in person or virtually

How do I get my DMR recordings?

 

Kraken is coming and we all need to prepare for its arrival.  On Tuesday October 19th 2021, Steve K2GOG was invited to the North Star Digital Net to give a quick chat about what does it do and why its important for the future within the broader topic of "software defined radio".

A few people who could not attend the live discussion had asked Jim WA2UMP and Steve K2GOG to see if they could record the audio presentation.   This is a fun problem that needed to be solved first to start this article, so read onward!

How do you record DMR audio?

Steve K2GOG planned to use his Alinco DJ-MD5XTG to talk via his hotspot which reaches the Brandmeister 31630 (STEM) talk group.  A nice feature with this radio, as well as the popular Anytone AT-878 series of radio, is that it can record transmit and receive audio with timestamps and by who was speaking.

Its easy to scroll through recorded audio files one by one or play all your recordings on a loop to play them all in order. This could be helpful if you thought you may have missed some important scheduled discussion or activity on your favorite talk group.

One annoyance is that the recordings save to internal memory on the radio instead of a micro SD card, like on radios such as the D-Star focused Kenwood TH-D74 or the Fusion based Yaesu FT-5DR. 

Both of those radios and even the Icom IC-705, all require the user to remove the SD card from the radio to access recorded audio but that makes it really easy to access those files  on your computer and send them to someone to share interesting transmissions like during a satellite contact. 

In the case with the Alinco and Anytone, you need to connect up a cable to your computer to access the recordings but you can not pull those files off which is super annoying. The manufacturers software seems to lock this function out but would otherwise clearly support this as pictured below.

If you click any of the files listed in photo above, the recording simply plays through the radio speaker but we are no closer to sharing the recordings.

The Alinco DJ-MD5 series of radio uses a simple USB micro cable to program the radio but does not output audio.  The way to solve this problem is to use the headphone port on the Alinco which uses the standard 3.5mm plug found on most all consumer headphones.

Using a 3.5mm stereo to stereo cable, the other end plugs right into the microphone jack on your computer sound card.  If you have a modern laptop which uses a TRRS (Tip, Ring1, Ring2, Sleeve) style connector, you may instead need to use a USB sound card as mentioned in Steve's explanation video below.

Now that we have that problem solved, you can use a program like Audacity with the sound activated record function enabled to "re-record" the audio from the radio to your computer.  While this takes a little while to do, it lets you easily stitch together the audio segments you want with no gaps. 

If you are over a certain age where you may remember double cassette recorders, this activity may bring back memories of less technological days when you had to get creative to make a mix tape from "borrowed" cassettes or maybe songs off the local broadcast station.

Hopefully this modern solution may give you some ideas on getting more from your DMR radio.

Getting back to Kraken

After all that, now we can finally get to the recording you might have missed! 

Here is an MP3 recording mostly of the segment from Steve K2GOG.  

It sounds like he missed a few parts but is otherwise complete. It looks like a time intensive operation to click on all recordings in order, so bear that in mind if you wish to do something like this yourself.

The recorder function works on any "over the air" DMR signal, so using it also to record simplex activity like what took place during the NEARFEST on US national DMR simplex of  446.075 MHz on time slot 1, color code 1 and talk group 99 is another idea.   

But, if you plan to record audio from Brandmeister you can also just use the "Hoseline" function and route that audio from a talk group into Audacity just as easily using virtual audio cables. 

And with that, I hope you are looking forward as much as Steve is to getting the new Kraken once its starts shipping in March 2022.

Learning about SDR with Rick + Get ready for the Kraken!!!

Software Defined Radio is eating the world.  SDR devices have become common place in both the amateur radio and electronics hobbyist world for many years now and the good news is that hardware comes at different prices in order to appeal to different users.

On October 5th 2021 during the North Star Digital Net,  Rick W1RHS, will be talking about the inexpensive RTL-SDR USB dongles and where they fit in along side other much more expensive devices aimed at the amateur radio community.

For under $30 USD, this popular RTL-SDR V3 has been covered before on HVDN and Carl Laufer who is the manufacturer of this SDR has even shared some HVDN articles on his very popular RTL-SDR.com blog

And, because HVDN and Jim WA2UMP who runs this excellent DMR weekly discussion are close friends with Rick W1RHS, here is a quick link to Rick's upcoming presentation which will be live on talk group 31630 (STEM) on Brandmeister next Tuesday.  

Its also possible to listen to the discussion without a DMR radio by looking for 31630 in the talk group list at https://hose.brandmeister.network/#/ 

What about the software?  What about the Kraken?

Rick covers some really great detail on hardware plus some ideas for software, which is really needed to get your "software" defined radio to do anything.

Between Rick's latest presentation and one that Steve K2GOG did a while back on "Sensing the world around you", you will see many of the same references to certain software, like SDR#, SDR Play, SDRangel and a few others. Since the below chart was created, another cross platform application worth a strong look is called SDR++

One area which both presentations did not talk about is something called a phase coherent software defined radio which actually combines multiple radio's together in order to provide very unique capabilities.

The RTL-SDR.com website not only offers its inexpensive SDR many just call the "V3" but also a device called the Kerberos and its upcoming really exciting update to this called the Kraken. 

This topic on phase coherent SDR is best left for another time, like how to change some code to use the older Kerberos hardware with the newer software meant for the Kraken.

Please give a listen to support Rick and his October 5th SDR presentation by marking your calendar now incase you have other things in the Hudson Valley or beyond taking place the same evening.

Presentation: NanoVNA Overview

Before the popular Hackaday website made the wider hobbyist world aware of the "Nano VNA", there has been continued discussion taking place on the Northstar Digital Net about this inexpensive device and its different capabilities.

Hudson Valley resident, Neil Goldstein W2NDG, recently gave a fantastic presentation in person at the Overlook Mountain Amateur Radio Club (OMARC) about this sub $50 USD device if shopped for carefully and its abilities for analyzing antennas, finding breaks in a length of feed-line, tuning filters and so much more.

Neil has shared his slides on his Fofio blog and real time discussion can be had with other users of the Nano VNA every Tuesday on the Northstar Digital Net run by Jim Miller WA2UMP. A copy of the presentation has also been added to the HVDN Presentation Library in the affiliated section.

For those not familiar with the Hudson Valley, the OMARC club is one of many local member driven organizations and caters to serving amateur radio operators in Dutchess and Ulster counties along with a wider reach into Columbia and Greene Counties.

Based on a quick chat with Neil who is a member of multiple organizations such as the Long Island Mobile Amateur Radio Club (LIMARC) to the south of the Hudson Valley, here are are some more details if you were not among those who attended the live presentation in Kingston, NY at the recent OMARC meeting.

What was the main reason you bought the Nano VNA?

Mostly for antenna analysis.  I have an antenna analyzer that I built from a project article, but it maxes out at 30 MHz.  It would be nice to have something for testing any kind of antenna I might use from LF antennas up through 70 Centimeter antennas.  I also have quite a collection of unidentifiable HT antennas that I can now test and label accordingly.  Additionally, it will come in handy for testing bandpass, and lowpass filters from some of my future kit projects.

Is it fair to compare a $50 USD Nano VNA to a commercial $11,000 USD piece of equipment?

In most cases I would say NO.  I see this argument all the time on some of the email groups where people complain that the IC-7300 just doesn't have as good a waterfall as the (insert $5000 radio here). We're used to seeing people comparing apples to rutabagas in this hobby.  In this case though, it holds up for casual use.  Very few of us need the accuracy of the $11K model, and something like this is what we have been looking for, but it's nice to know that it does compare on some level.

Will it replace any other "test equipment" you currently use?

I'll probably not use my homemade antenna analyzer much anymore.

What do you think is the best way to get started with the Nano VNA?

There are multiple websites with getting-started articles on these, as well as a very active Groups.io group.  Buy a decent one (Amazon seller KKMOON is where I got mine) and start with learning the calibration steps, and try out the basics.  Stick a Baofeng antenna on it and run SWR.  Watch some YouTube videos.  There are plenty to choose from.

How would a user know the readings they see are accurate?

Test a known quantity.  Maybe an antenna from a major-brand radio, although the cheapies are surprisingly accurate.  My Baofeng dual-band antennas showed clear SWR dips at 446 MHz and 146 MHz.  Test a commercial lowpass or bandpass filter with a known cutoff.  Compare output from the device with someone else's antenna analyzer output if you don't have one.   

Why is your blog called Fofio?

Fofio was the name of my imaginary friend when I was 2-3 years old.  I think the name was some sort of toddler-mispronunciation of Volvo, but I'm not sure.  It was also the name of the only dog my family had when I was growing up (named by guess-who).

Are any other "test and measurement devices" on your radar for the budget minded hobbyists?

There will be future versions of the NanoVNA coming with more capability and more features.  Watch the forums, and the groups.io NanoVNA group for info.  Other than that, I have seen several very inexpensive scope projects around.  I don't know of any specific ones, but the large buildathon at this years FDIM QRP get-together was focused on one of these cheap oscilloscopes.  Simple spectrum analyzers are also out there, based on RTL-SDR dongles, or SDR radios like the AirSpy and/or SDRplay models.

Nano VNA: Further Reading

If you have not already seen Neil's great presentation, he includes some helpful links and we are sharing them here just for back up.  Hudson Valley Digital Network (HVDN) looks forward to sharing more about this great piece of equipment in future articles, on the air discussion and at various in person meetings.

• Hex and Flex getting started 1, 2, and 3:  https://hexandflex.com/category/uncategorized/

• Electronics Notes, What is a VNA?:  https://www.electronics-notes.com/articles/test-methods/rf-vector-network-analyzer-vna/what-is-a-vna.php

• nanoVNA vs. Keysight N9913A at HF: http://ae5x.blogspot.com/2019/09/nanovna-vs-keysight-n9913a-at-hf.html

• Original Project at GitHub:  https://github.com/ttrftech/NanoVNA

• RTL-SDR posts about NanoVNA:  https://www.rtl-sdr.com/tag/nanovna/

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.

North Star Digital Net: Presentation on BlueDV

The weekly North Star Digital Net held every Tuesday evening at 9:00 PM Eastern on DMR talk group 31630 (STEM).  Any amateur radio operator is welcome to attend. 

Access via All-Star and Echolink is possible to through Hudson Valley Digital Network with details on that at stem.hvdn.org for those without a DMR radio or not able to use a radio at the time of the discussion.

Net control, Jim WA2UMP often turns over the floor to someone knowledgeable on a specific topic followed by a Q&A  session.

This week featured Rick, W1RHS who shared information about the popular BlueDV application. BlueDV allows you to create a hotspot for digital ham radio modes under Windows, Linux, Android and iOS. 

BlueDV allows you to create a digital communications platform under these operating systems using only a computer, tablet or phone and using the computer or devices speaker and mic.  

The presentation covers the DVMega radio/modem board combined with the BlueStack board for USB or Bluetooth connectivity and the AMBE 3000 dongles with AMBE Server.  

There is a comparison between BlueDV and PiStar and a review of the DVMega Cast network radio. Not covered in the presentation is "Peanut" which is one of many growing applications used to augment access into digital voice infrastructure today.

Download a copy below and be sure to check back next week if you have further questions.

More details:

• North Star Digital Net

• BlueDV for Digital Ham Radio Presentation