Showing posts with label MHV TG 31368. Show all posts
Showing posts with label MHV TG 31368. Show all posts

Tuesday, October 2, 2018

October 2018 Global Digital Repeater Round Up

It is truly amazing to see such tremendous growth in digital voice modes the last two years.

What started for Steve K2GOG in 2016 as a theory can now further be validated by fact. DMR was the right technology to invest in as it relates to amateur radio digital voice technology.

In October 2016, he presented an overview of competing digital voice standards at one of the local Hudson Valley of New York amateur radio clubs located in Ulster County. 

Since that point in time, he has taken 4 probes of the total number of repeater counts globally as well as for those just across New York State.

The current global state of just what will be now further defined as "wide area digital repeaters" has seen DMR grow an amazing 78.03% in a two year span. 

Wide area repeaters are one of the best ways to measure growth of digital voice mode adoption because the equipment needed is expensive.  Repeaters usually are only worth the investment if users have appropriate equipment that can access them.

So, a little of "what comes first, the chicken or the egg" scenario usually happens when it comes to repeater deployments.

The N2MCI DMR repeater in Kingston, NY has a core coverage
area in red and extended coverage area in green.
Since repeaters can be expensive and are designed to reach a wide audience of users typically located in a 30 to 60 mile radius, the operators of repeaters typically list these infrastructure resources on the repeaterbook.com website to make it easy for amateur radio users to find out what repeaters may be worth programming into hand held or mobile radios.

The repeaterbook.com website is not 100% perfect as a data source, but comes pretty close to chart growth patterns of amateur radio repeater deployments

The below chart shows the other major digital voice mode repeaters globally at various points in time over the last 2 years.


DMR:  Reasons Why It Grew The Most

Before we get to DMR, lets explore the second highest globally adopted digital voice mode known as Yaesu Fusion.

After a few years of being on the market alongside the Icom D-Star system, both vendors offered comparably priced digital voice equipment and few options to choose from.

The average cost of a digital voice capable hand held radio was just above $300 back in 2016.  This inhibited adoption of Fusion and has certainly had a negative impact on Icom D-Star.

FT-70DR review
The Yaesu FT-2DR when released in 2015/2016 was priced at $379. The 2018 FT-70DR which
also offers Fusion and less robust enhanced features found on the FT-2DR is only $169.99. Currently there are 3 Fusion dual band handheld radios for sale compared to 2 Icom D-Star models

In 2018, Yaesu released the FT-70 dual band FM and Fusion radio which is currently priced at well under $200. This is one reason that made it easier to adopt Fusion thanks to more aligned features and pricing to help it catch up to DMR which has mostly had lower priced equipment from the start.

Prior to Yaesu releasing this moderately priced FT-70 hand held radio, they also released some nicely priced mobile radios as well to help build out the overall ecosystem of Fusion capable radios available for purchase.  Icom in comparison has not done this.

This should partially explain the flat growth of Icom D-Star compared to Yaesu Fusion.

Getting Back To DMR

DMR is an open ETSI standard which made it easier for vendors to offer a product at a good price without having to pay to license technology such as D-Star which is majority owned by the Japanese Amateur Radio League. 

In October 2016, Fusion and DMR had just about the same number of repeaters globally and almost grew at the same pace until mid to late 2017. In 2018, things are clearly different with DMR.



With more dual band DMR options available both in hand held and mobile radio design, users have certainly taken notice and likely helped influence DMR repeater deployments.

As of October 2018, there are now 5 different manufacturers of dual band hand held radios and a few more models spread among them. Examples include:



What about NXDN and P25?

NXDN and P25 are aimed at commercial users, but the amateur radio community has started to use surplus or retired equipment within the VHF and UHF amateur spectrum.

Adoption is low, but its still too early to tell if either of these options in the next 3-5 years will replace DMR as it relates to amateur radio.


Predictions for 2019 Digital Voice Ham Radio

Hopefully this is not going too far out on a limb, but here are the predictions for the coming year.

Alinco was the first main stream vendor to offer a DMR radio with its MD-40, but saw little adoption due to price compared to similar radios like the MD-380.



Alinco's new MD-5 looks like it will be a winner based on features and price and may get the later adopters interested in DMR in case they do not trust some of these newer vendors listed above.

It has been rumored that Alinco, Connect Systems and possibly one other vendor will offer new dual band mobile radios in 2019 as well which will likely go over well globally.

Excluding hotspot devices, network radios and cross connect systems which will all be covered in future articles, it seems that DMR is as close to an FM analog replacement technology within amateur radio.
Perhaps Icom, Yaesu or Kenwood will release a DMR radio in 2019 based on market demand and lost opportunity.
What do you think are some likely predictions for digital voice repeaters or radios in 2019?





Thursday, June 21, 2018

Watch! Two Time Slots & SDRangel In Action

DMR is confusing for some people. SDR is even more confusing for others.  What happens when you combine the two?  Mass hysteria?  Global epidemics? Accelerated excitement?

Due to a delay in circuit board re-design for the the Modern Field Strength Meter project, we bring you something different for this week (and possibly next)

This article builds on past written content and accompanying videos to show some of whats possible today when combining the two.



Some Brief Background First

DMR has seen a lot of growth because it is cheap to get started and talk around the world.  SDR adoption for many started with inexpensive USB dongle type of receivers before moving to something more capable. Many SDR dongle purchasers hoped to hear signals from around the world using these cheap receivers.

For a sum total to a new ham who may invest less than $300 in the amateur radio hobby, they can purchase a dual band DMR/FM hand held radio, multi-mode digital hotspot, USB SDR dongle and a few accessories such as antennas, power packs, etc. All this gear permits both local, global and emerging aspects of the hobby to collide and find people with like interests to talk with others about.

For comparison, when I got started in the hobby in the mid 1990's, the starting point for many was a VHF only Radioshack HTX-202 handheld radio for about the same $300! This permitted only local communication and while it still works today, there is a world beyond 2m.

“You realize that our mistrust of the future makes it hard to give up the past.”
Radio Shack is out of business by the way...

With DMR being the most popular digital voice mode that permits  local and global communication and an SDR being able to receive voice and non-voice communications locally and globally, there is a lot of capability at hand today for a new ham. Compared to local VHF activity, DMR provides the ability to talk with not the same local people all the time, but with the voice quality of local repeaters.

Many new hams experience getting on the air for the first time on the VHF 2m band and some quickly tire by talking to the same few people generally about the same thing. If there are not enough common interests with those locally, that new ham often decides the hobby is not for them.

Even so, many new hams who tire of 2m and move on to HF for long range discussion, get frustrated by higher expense, more planning for antennas and potential lack of people with common interests to talk to depending on when HF bands are stable or not.

The Best DMR Feature

DMR uses similar technology to second (2G) and third generation (3G) cellular communications known as TDMA.  The unique thing about TDMA based DMR is its ability to have two discussions on the same frequency at the same time with zero interference.  More about that here on HVDN.

Many have heard this, but not seen it in action.  Here is a brief video:


The laptop in the foreground is running SDRangel software that is receiving signal from a dual time-slot hotspot on a SDR nano3 USB dongle. The frequency for this test on my dual time slot hotspot is 432.565 MHz.

The SDR Nano v3 retails for less than $30 and is very small.
A standard SD card is shown at left for size comparison
.


On the laptop in the video background is showing the call-sign, time slot and talk group (virtual frequency) as its received by the hot spot.

The audio is being output by the foreground laptop and you will see how it coincides with the information on the background laptop.

This test was conducted at a time when a lot of activity is present on popular DMR talk groups known as TAC310 and Worldwide 91.


The same SDR dongle can be used to receive signals from local amateur radio repeaters that are DMR, analog FM or even some less popular modes such as Yaesu Fusion, Icom D-Star and commercial focused NXDN and P25.

As evidence by the video,  both local US and international amateur radio operators are able to talk to one another without having to invest in large antennas or high powered radios such as those used on HF for voice communication.

What is fascinating about DMR is how many of the older ham radio operators have taken to DMR for casual discussion instead of just using HF.

You never know who you will hear on amateur radio and where they are from. Investing in modern technology will allow a new or experienced ham to try new things for little expense before deciding where else to invest in.  This "modern ham" starter package may cause reason for purchase for things such as:

  • An HF radio
  • Outside HF, VHF or UHF antennas
  • A better computer 
  • A higher end SDR
  • Getting better educated about SDR and DMR
  • More education on computer/ham convergence
If there is interest in anything mentioned in this article, look for many of the HVDN members on DMR TG 31368 which is geographically focused for those residing in the mid Hudson Valley of New York. 

You can also look for discussion of combined topics on the new STEM talk group 313630.  More detail about that and its focus here stem.hvdn.org