Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

   Home   Help Search  
Pages: Prev 1 2 [3]   Go Down
  Print  
Author Topic: Dstar and Emcomms  (Read 17953 times)
AE6ZW
Member

Posts: 100


WWW

Ignore
« Reply #30 on: May 02, 2011, 01:13:05 AM »

I heard internet was one of the most useful things in japanese earthquake.  may 10 ghz d-star back born to connect shelters or connecting eoc  to eoc  or connection to winlink system may be useful,  i guess we can use d-star as emergency internet link.  1.2 ghz dd also can be used but it s limited to 128 kbps
Logged
AB8OU
Member

Posts: 3




Ignore
« Reply #31 on: May 05, 2011, 12:49:52 PM »

 From my reading of the comments on this forum, it appears that many assume that DStar infrastructure is only the repeaters and link to the internet.  I consider the actual physical DStar radios in the hands of hams to be the most important part of the infrastructure.  If you don't have radio's to talk to others, there is no communications.

Looking at some crude numbers, there appears to be about 700,000 licensed hams in the US and about 22,000 repeaters.  This works out to about 32 hams per repeater, assuming every ham gets on a repeater.  From the ICOM offers, it appears that they feel that you need 10 users minimum to keep a DStar repeater on the air.  My quick and dirty count showed about 300 DStar repeaters in the US.  At 10 users per repeater that works out to about less that 0.5% of the US ham population.  With 32 users per repeater, market penetration goes up to almost 1.5% of the US ham population with approximately 10,000 DStar radios.  If the adage that "The first thing every ham does when he receives his license is to buy a two meter handheld." is true, two meter FM probably has greater than 90% market penetration.

Questions that need to be considered are;

1.  How many DStar equipped hams could you turn out in a disaster situation including consideration that only 25% of your group will be available in a disaster?

2.  How many of your government and other served agencies have DStar equipment installed as compared to VHF/UHF FM?

3.  How many DStar radios can ARRL provide under their HAMAID program to a disaster scene?

4.  How many of the walk-in or mutual aid hams will have DStar radios with them?

5.  How many owners of DStar radios will be willing to leave their expensive radios behind when their shift ends?

Having gotten in to ham radio when the AM/SSB war had reached the point where the technical superiority of SSB was being accepted, it still took almost 10 years and the availability of much less expensive SSB gear before SSB dominated the HF bands.  Even so, most HF rigs today still include the ancient modulation mode.

In the ARES group that I am a member of, I am not aware of any members that have DStar capability.  One or two may have DStar capable radios but have not seen any reason to spend the extra dollars to add the DStar board.

Until DStar has significant penetration in the ham population, basing an emergency communications plan on it would appear foolhardy at best.

zeke
Logged
K1CJS
Member

Posts: 5878




Ignore
« Reply #32 on: May 09, 2011, 07:42:09 AM »

Zeke, it isn't only the radios that form the infrastructure.  It is also the cabling and the other parts of the station.  Many hams already have these things, and if it weren't for the high cost of D-star equipment, possibly many more hams WOULD have them.

In case it slipped your mind, there is a pretty bad recession that this country is trying to come out of right now, and all too many hams don't have that much in the way of disposable income.  For many of us, those new radios will just have to wait--and D-star digital STILL isn't as good as plain old FM and the digital modes used with it.
Logged
KD8NGE
Member

Posts: 35




Ignore
« Reply #33 on: May 09, 2011, 08:18:09 PM »

Our local clubs seem to think it has a future.
At this moment I can't afford to purchase a D-STAR capable radio, and I lack the expertise to convert an existing rig.
I know my Yaesu has WIRES capability, but no repeaters nearby ... another good idea shot.
No, D-STAR is something I'm going to sit back and watch for a while.
Logged
AB8OU
Member

Posts: 3




Ignore
« Reply #34 on: May 10, 2011, 02:05:54 PM »

Chris

I agree that the required infrastructure is everything involved in the communications loop, including the power sources, cables, antennas, radios, repeaters, computers, internet connections, and the ham operators.  I was trying to comment on the earlier comments that were limiting consideration of the infrastructure to the repeaters and the internet connection.  Price is definitely one of the factors impacting D-star adoption. However, I think the majority of the US ham population having not accepted D-star as either a superior technology or the apparent winner in the digital mode de Jour race as being much larger factors.  The one "early adopter" of D-star that I hear on the air now spends more time mentioning the problems and limitations than how great it is. 

Internet connectivity between radios is available with analog voice as well as through D-star.  My impression is that locally ham radio VOIP activity, such as Echolink, has greatly decreased from what it was a few years ago.  Many local repeaters seem to have dropped their connections with the internet along with phone patches due to lack of use.  My suspicion is that many have discovered that the radio is really not needed for internet chatting.

The recession is not something I had considered as impacting D-star sales even though I am one of those who got 'retired' earlier than planned.  D-star or D-star compatible radios did not even make my short list last year when I added dual receive FT-8900 and VX-7R radios to the collection. ICOM radios had dominated my shack and actually continues to dominate it, even with the new radios.  My selection criteria was based on dual receive, additional bands beyond 2M & 70cm, and of course price.  D-star capability did not add any points to my evaluation and hurt on the price.

I still have not decided if D-star is the future or just another flash in the pan.  Currently it does not offer anything I really need or even that I wish I had.  Right now, my long term acquisition wish list includes a back-up hf radio and a hf mobile radio but no D-star radios.  Only time will tell if D-star is a solution looking for a need or desire to fill or an actual solution to a real need or desire.
Logged
K1CJS
Member

Posts: 5878




Ignore
« Reply #35 on: May 17, 2011, 10:42:23 AM »

Zeke,

I'd say flash in the pan.  For instance, there are instances where D-star equipped radios can NOT get through while traditional FM rigs will.  They'll get through poorly, but the FM rigs WILL GET THROUGH.  Granted that those instances are fringe communications instances, but they still show a weakness of D-star equipped radios, and nothing done so far has gotten past that weakness.

Concerning the recession, most of the people in emergency communications are of a younger age.  Granted that there are older hams mixed in, but the younger ones are the ones that the recession affects more.  They're still trying to put together their homes, take care of their families and pay their mortgages.  They have less available disposable income.

BTW, nice to find someone who can sit down and construct a reasonable response to a posting.  Too many of the people who post here can't be bothered to do so.

73 and take care!  Chris, K1CJS
Logged
KS4VT
Member

Posts: 141




Ignore
« Reply #36 on: June 16, 2011, 05:14:08 PM »

It only takes one (1) person without the capability to force everyone to go back to analog, so with that being said you must plan for the lowest common protocol available to everyone.  Even public safety, with their exotic digital trunking systems have a plan for analog mutual-aid repeaters in all of the bands (VHF, UHF, and 700/800) for incoming resources that will not have access to the local system(s).

My vote would be for voice communications everyone stays analog because you never know who is going to show up to help.
Logged
G8KHS
Member

Posts: 22




Ignore
« Reply #37 on: June 18, 2011, 12:37:57 AM »

When you have a disaster, systems with their infrastucture dependent on grid distributed power supplies cannot be considered reliable.

The first line emcomms used in the Japanese tsunami disaster was HF radio on 40m.

If I had to trust a single radio system with my life and the lives of others it would be HF based analog SSB or CW.

73 de G8KHS - John
Logged
KC8OYE
Member

Posts: 297




Ignore
« Reply #38 on: June 18, 2011, 08:03:17 PM »

I agree with a lot said here.

D-Star is kinda cool...

that being said.. it is a lot more complicated which offers a lot more to go wrong..

it is very expensive.. so if you decide to use it for emcomms, now you have to get every responder equipped with it.. and I don't know how things are in your counties, but around here, we have enough trouble just getting enough bodies to show up for a fire coordination, let alone bodies with RACES cards (As required by the county), let alone bodies with RACES cards AND D-star radios.

I also have a big problem with it being ICOM-only right now. I'm not speaking to it being proprietary.. just that nobody but icom makes them right now. (my expierence with icom has been less then spectacular too)

for my money, I'll stick with basic FM. 

like someone else said, I just picked up an FT-8900 myself.. $400 for 10m,6m,2m,70cm FM only.. vs $800 for dSTAR radio that only does 2m/70cm? nahh.
Logged
KB2FCV
Member

Posts: 1141


WWW

Ignore
« Reply #39 on: June 23, 2011, 11:42:19 AM »

I am a new user to D-Star. I bought it mainly just to see what it was all about (I was in need of a new mobile rig).

The simplex stuff with D-rats software is defintely neat! I can see where people in emergency communications would like that to send messages, lists, etc around if the internet is unavailable. I would think any EOC would want D-star as an added capability. The whole DVAP/DV-Dongle stuff is neat

It is cost prohibitive and not quite widespread enough. I think one way to help spread it out is to get the technology more available by lowering cost and having other manufacturers offer it. If I recall correctly JARL owns the technology, not Icom.

That being said, it's been fun playing around with it and I've met some real nice people on the repeaters/reflectors.
Logged
KC8OYE
Member

Posts: 297




Ignore
« Reply #40 on: June 23, 2011, 11:57:43 AM »

the funny thing is. we already do everything D-star does with Packet radio on a separate frequency in our emcomm group..

we can send files back and forth, lists.. etc.. we even do damage reports via packet radio.  and standard 2400 buad AFSK packet can be sent via any voice repeater Smiley

as i've said, I'm not saying D-star isn't cool.. nor am I saying it doesn't have it's place... BUT.. to "RELY on it for emcomm" i think that's just going to be hinderance in 'the heat of battle'... I've been out on skywarn ops when all heck broke loose, and i never once thought "boy I wish I could send data right now" ...

for our non-emergency public comms.. D-Star would be a fabulous tool however...


Logged
K1CJS
Member

Posts: 5878




Ignore
« Reply #41 on: June 24, 2011, 09:15:16 AM »

D-star does have capabilities that packet radio doesn't.  Can packet use the same frequency (bandwidth) for voice and data at the same time?  No, it can't, but D-star can.  That is its only really new capability that is worth much.  Other than that, it is a glorified voice/packet system that sometimes can't do the job that regular comms can in fringe areas.
Logged
KC8OYE
Member

Posts: 297




Ignore
« Reply #42 on: June 24, 2011, 01:54:36 PM »

k1cjs

that's kind of what I was getting at... I've never found myself going 'boy I sure wish I could do xxx right now"... and xxx being anything that D-start could do.
Logged
AE5JU
Member

Posts: 223




Ignore
« Reply #43 on: August 08, 2011, 09:48:58 PM »

Is it true that the term "D-Star" is a registered trademark of Icom?  If so, how does this make D-Star attractive to other manufactuers?

73,
Paul - AE5JU
Logged
AE6ZW
Member

Posts: 100


WWW

Ignore
« Reply #44 on: September 11, 2011, 04:42:08 AM »

D-STAR would be good option for emergency communications used by specific groups such as RACES, or shelter to shelter, EOC to EOC communications,  they takes less bandwidth than FM.  and has Data  capability.
Logged
Pages: Prev 1 2 [3]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!