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D-Star – a Delight or a Disaster? – Another Perspective – Guest Author 29 - July - 2008

Posted by k9zw in Amateur Radio, Emcomm, K9ZW Just Rambled.
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Jeff WA4ZKO has been kind enough to pen a guest article on the D-Star scene:

 

 

WA4ZKO's QSL Card

WA4ZKO's QSL Card

 

I’m a repeater sysop myself and know many others. The going trend across the country is that most analog repeaters set silent 99% of the time. I can’t count the number of sysops that have told me they are going to run current gear till a major repair comes up, then it will fade away. Even SERA had an article in their journal magazine about “where have the users gone” not so long ago.

So? Conventional repeaters are fading away one by one due to lack of activity. I just don’t see that the introduction of DSTAR repeaters is going to change this trend. We’ll just have more repeaters, even more expensive to install/maintain, setting around idle most of the time. Sure, you might get a burst of usage in the beginning that quickly fades as the “new” factor wears off. DSTAR has been around for several years now…nearly a decade?

I find it interesting that only ICOM offers DSTAR gear and none of the other manufacturers have joined in after all these years. Plus when you factor in the poor quality of most ICOM gear of late, not good. In fact I gather DSTAR gear sales have been so poor they recently started all kinds of promotions. The only DSTAR system in my area is, interestingly, heavily sponsored (read subsidized) by the local ham radio gear dealer and ICOM.

I’m also disturbed by the misinformation (outright lies at times) and exaggerations often used by the DSTAR crowd when it comes to “is this a repeater or not,” and the comparisons with APCO25.

Then to build this on another proprietary CODEC is, IMHO, a big mistake. Why reinvent the wheel when a well defined digital standard already exists. It would of been much wiser to use a interoperable standard (ah, APCO25 anyone).

Yeah, I know the codec is still proprietary JUST LIKE DSTAR’s. At least this would offer INTEROPERABILITY options for those that want to have commercial/ham channels in one rig..legally. Plus it would allow hams a great deal of choice in terms of obtaining commercial grade gear to be used for the repeaters…just like we do today with analog repeater hardware. ICOM’s repeaters have never been known to be a very good value and reliable.

From what I’ve seen of it, DSTAR would be an administrative nightmare to use in a typical real world emergency. This is especially so if you’ve got users coming in from out of the area to assist and they are not already setup on the system. Not to mention the potential for system failure with such a setup. The audio quality of DSTAR leaves a lot to be desired in comparison to just about any P25 radio I’ve used. The P25 commercial gear is unarguably much more durable than ICOM’s toys anymore.

In many cases, APCO25 gear can do both analog and digital. DSTAR repeaters (sorry, a repeater is a repeater) are digital only. Yes, the mobiles/handhelds can do analog FM and DSTAR, but not the repeaters. Granted you probably wouldn’t want to be doing both on the same system on a daily basis, but it’s a nice fall back option to have there. AKA, flexibility.

Before someone comments that APCO25 locks you in to Motorola gear, it just isn’t so. You can buy all kinds of APCO25 gear from a multitude of manufacturers. APCO is a public safety group that defined the standard, a standard created with a lot of thought towards the future, interoperability, and preventing vendor lock in. We hams don’t know it all and could learn a lot from today’s communications leaders and pros.

Most hams are just glorified appliance operators anymore. That’s not always a bad thing, everyone is in the hobby for their own reasons. Problem is that many need to learn just how far behind the rest of the communications world we are. A great example was the hoopla created when SERA tried to get the 2m repeater owners to adopt PL tones (something public safety adopted decades ago). Yeah, the way SERA went about it didn’t help, but to read the rational behind the resistance to it was an eye opener for many as to why our hobby stands where it is today. Even Riley Hollingsworth made comments that made it clear we needed to get at least halfway in sync with the rest of the communications world!

Many of your repeater owners are going to want to carry commercial gear on their hip, not a 2nd radio just to work DSTAR. It would of been much better to take the existing digital standards and design for interoperability. I’ve been around a lot of this group and they are not impressed the DSTAR gear and choices made. Digital is the future for sure, but implementation is key.

If they wanted a data layer, then strap it on top of an existing standard and allow backward compatibility to APCO25. This layer should be completely open and extensible. Let us hams do what we used to do best…innovate. Seems we didn’t learn much from Katrina and 911.

No I’m not saying that the average ham needs to be able to access a local public safety system via APCO25 using ham gear. In most, if not all cases this would be illegal for a variety of reasons. But what many need to realize is just how many hams that are active in public service are also employed in public safety. As radio systems are upgraded across this country, guess what’s replacing them? APCO25 gear. Many of these guys/gals are already carrying high quality APCO25 gear on their side are not going to go for yet another expensive digital radio because ICOM couldn’t go with a standard. Hence ICOM immediately lost themselves a good chunk of users, users that are often the front and center face of ham radio to the agencies we serve. Give this some thought folks.

From what I gather from my travels and talking with other repeater sysops, most hams going digital are deploying P25 commercial grade gear. These P25 repeaters are seeing more interest/usage than comparable DSTAR repeater systems, but even they admit that usage is nothing compared to the 80’s and 90’s. In general the attitude from these guys is that if you’re going to do digital repeaters, then you do it right and use an open standard like P25. Yeah, P25 stuff is expensive, but DSTAR isn’t cheap either. Both will come down over time and P25 surplus gear is already pretty easy to find on ebay.

Many other concerns about DSTAR exist, but I think just the above will prevent it from ever being anything more than a niche toy. The sad part is that if it had been done right, we wouldn’t be closing in on nearly a decade of DSTAR with so little actual usage beyond a few highly vocal niches.

Both DSTAR and APCO25 are interesting technologies with pros and cons both ways. In the end things will have to stand on their own merit, not hype. I predict ICOM and the DSTAR folks are going to regret their choices.

73

Jeff
WA4ZKO

Link to Jeff’s Web Blog 

WA4ZKO’s Ham Radio & IT Weblog

I find myself agreeing with Jeff WA4ZKO’s take – D-Star has too many issues to be a viable Emcomm tool and remains a limited Amateur Radio experiment after years of full scale pushing by Icom.`

73

Steve
K9ZW

Original Article: D-Star – a Delight or a Disaster?

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Comments»

1. Mark Morgan kb9rqz - 31 - July - 2008

I like the looks of say d-star but I look at the cost and my wallet reachs out for my throat

I can’t see what about it cosy so much more than than the Non D-Star product

2. k9zw - 31 - July - 2008

Perhaps the cost is in part to recover the cost for the very expensive CODEX, which as discussed is NOT public domain.

Recently several DRM software packages were pulled out of circulation until they could be rewritten to use a Open Source DRM CODEX.

D-Star is in the same boat, if the CODEX license is pulled the expensive D-Star gear may well be idled.

73

Steve
K9ZW

3. Scot, KA3DRR - 3 - August - 2008

Compelling. Insightful. And straight from the heart. One of the best I’ve read in awhile.

Jeff, thank you.

73
Scot KA3DRR

4. Mark Morgan KB9RQZ - 7 - August - 2008

wll I don’t know the answer and since asking question and geting answers is how we all learn thing and I am never shy to admit the limits of my knowledge

why would the codex be so costly or what makes the codx so expensive?

or rephrase the question to something where you copuld answer if possible

now anyone that is curious will hopefully get an answer because I would ask

5. k9zw - 7 - August - 2008

Hi Mark KB9RQZ

The CODEC is a bit of intellectual property.

Programs use various CODEC to essentially do the heavy lifting in translating from a format the machine uses internally to the transmission format and also the reverse on receive.

See http://encyclopedia.thefreedictionary.com/Codec for more.

CODEC is related to CODEX which were the sort of “Master Books” in Latin to share ideas during much of the Dark Ages and after.

http://encyclopedia.thefreedictionary.com/Codex is an interesting aside on that topic.

Back to CODEC costs, if a CODEC developer has invested (or is just clever enough) to create a significantly better COmpression/DECompression routine, then they often charge the market to recoup their inventions investment and to further make a profit as a reward for risking the CODEC’s development costs.

There are interesting aspects of fee-model CODEC businesses – even where software devlopers will settle for a “good enough” CODEC rather than their ideal, based on a lower delivered cost.

Hope this helps!

73

Steve
K9ZW

73

Steve
K9ZW

6. Ralph Javins, N7KGA - 8 - August - 2008

Good morning;

Regarding D-Star and the CODEC for it: I thought that it was in the public domain, having been developed by the JARL Digital Committee and was then handed to Icom for use in their radios. It was also offered to the other Japanese radio manufacturers.

There are many claims made for the capabilities of the D-Star System, but I have not yet seen any clear demonstrations of any significant advantage of D-Star over conventional voice FM. Speaking of conventional voice FM, the D-Star demonstrations I have heard have not been convincing of any superior voice quality. To me, the D-Star voice quality reminds me of some of the narrow band cellular telephone channels where I must ask for repeats to get the message to me. It is not always that clear.

The data capabilities will not live up to the expectations of the data users they are courting, but that is due more to the users’ expectations than any real deficiency in the data mode capability. The claims of “Internet like data capability” that I have heard from some proponents I think are coming from people who have never used 2 Meter 1200 Baud packet. At least the D-Star literature does say that the 128 Kb data rate is found only at 1.2 Gc and above.

I do have some questions about the pricing of the D-Star equipment. Please note that I do have a 2 Meter D-Star equiped radio, but there are no 2 Meter D-Star repeaters that I can find in the Puget Sound Area. I have never used my own radio in Digital Voice Mode. Yes, I live in Icom-America’s backyard, but we do not yet have much in the way of D-Star capability here. One of the main objections I hear is the pricing; the lowest cost D-Star radio for 2 Meters in the HRO catalog is $ 470; $ 330 for a 30 mm by 38 mm PCB addition to a $140 regular 2 Meter FM radio to make it also able to talk D-Star. That is over twice the price of the whole radio just for the PCB.

Technical CODEC comparisons aside, if Icom-America is truly interested in developing D-Star in North America, someone in their marketing group needs to look at the numbers.

Enjoy;

Ralph Javins, N7KGA
n7kga@arrl.net

7. k9zw - 8 - August - 2008

Hello Ralph N7KGA !

Thank you for reminding me that I’ve never explained how the D-STAR Standard (which is openly available) is different than the Advanced Multi-Band Excitation (AMBE) CODEC.

D-STAR as a standard covers much more territory than just an agreed Voice CODEC. It covers every aspect of how D-STAR units “talk” to each other, from handshaking & link establishment, to in the case of Voice, how they will use a common CODEC.

Advanced Multi-Band Excitation (AMBE) is the CODEC the D-STAR Standard calls for when in Voice Mode.

Advanced Multi-Band Excitation (AMBE) is a very powerful proprietary & commercial speech coding standard developed by Digital Voice Systems, Inc. and is NOT open source.

Digital Voice Systems, Inc. licenses the AMBE CODEC for D-STAR use.

It is the Digital Voice Systems, Inc. business plan to usually only offer their CODEC products as dedicated IC Chips.

Though their is potential for someone to write an open source substitute for the AMBE CODEC it is unlikely due to the closed nature of AMBE, the development costs and the likely expensive legal battle with DVS Inc if any question of intellectual property rights presents itself.

Additionally as AMBE is usually an embedded firmware carrying chip, there is less opportunity to substitute a new CODEC in existing D-STAR equipment if a new standard would be selected – it could even be that DVS’s licensing might preclude moving away from AMBE (the licensing agreement is not available, and may be considered proprietary.)

This doesn’t mean that AMBE isn’t a fine product – but rather D-STAR in Voice Mode is dependent on a licensed Close-Source Commercial CODEC Product that not only adds significant cost, but leaves an entire portion of D-STAR a technical mystery.

73

Steve
K9ZW

8. Gary KN4AQ - 22 - August - 2008

I’ve been following D-STAR development for some time now. I’m not a total advocate, but Jeff (and other respondents) had his own exaggerations and misinformation, so here are my comments in reply.

First, the AMBE 2020 chip costs $20, and you can buy one from DVSI in lots of one. Normally they sell a minimum of five, but they’ve made an exception for hams and the 2020. It is proprietary, but not expensive.

“I find it interesting that only ICOM offers DSTAR gear and none of the other manufacturers have joined in after all these years.”

All these years? D-STAR didn’t really start moving until the 2006 Dayton Hamvention, when ICOM introduced the ID-800 dual-band mobile and IC-91 Handheld. Before that, the product line was quite limited. That’s two years now to launch a whole new technology. I’d call it an infant.

I would be nice if other manufacturers would join ICOM and offer more variety, though ICOM’s product line is now pretty deep in D-STAR. Why don’t they? Kenwood was a D-STAR development partner, but pulled out of the Amateur market and focused on a commercial derivative.

“I’m also disturbed by the misinformation (outright lies at times) and exaggerations often used by the DSTAR crowd when it comes to ‘is this a repeater or not,'”

The vast majority of the D-STAR crowd considers D-STAR systems to be repeaters, and only consider operating them in repeater spectrum. A few D-STAR system owners, mostly in California and desperate for spectrum, skated on the thin ice of a misunderstood exchange of misleading correspondence with Bill Cross at the FCC to claim that it was not.

“Then to build this on another proprietary CODEC is, IMHO, a big mistake. Why reinvent the wheel when a well defined digital standard already exists. It would of been much wiser to use a interoperable standard (ah, APCO25 anyone).”

DVSI makes both chips – AMBE for D-STAR (and other uses) and IMBE for P-25. So maybe it’s not a whole new wheel. Does anyone know what it would take to license P25 technology for ham equipment? When I interviewed their sales manager (that’s where I got the $20 quote), I didn’t ask about IMBE.

“it would allow hams a great deal of choice in terms of obtaining commercial grade gear to be used for the repeaters…just like we do today with analog repeater hardware.”

I know a ham who is about to put a commercial (GE MSTRII) repeater on the air with full D-STAR compatibility, using the AMBE-2020 codec. I don’t think ICOM’s rather weak repeater offering will be the only options for long.

“From what I’ve seen of it, DSTAR would be an administrative nightmare to use in a typical real world emergency. This is especially so if you’ve got users coming in from out of the area to assist and they are not already setup on the system.”

Getting set up on a D-STAR system consists of one “ker-chunk” and the repeater puts it’s call in the proper slot in your radio. But it’s true that there is a learning curve with D-STAR, and hams who have trouble programming CTCSS will have more trouble with D-STAR.

I’m not sure what the “administrative nightmare” would be. D-STAR repeaters work pretty much like analog repeaters. Control of who comes and goes through the network (the Gateway) is weak. Repeaters in use for an emergency would probably want to set up a separate network so they’re not subject to intrusion by hams who don’t know what’s happening.

“Not to mention the potential for system failure with such a setup.”

Why would it be any more or less failure-prone than any other repeater system?

“The audio quality of DSTAR leaves a lot to be desired in comparison to just about any P25 radio I’ve used. The P25 commercial gear is unarguably much more durable than ICOM’s toys anymore.”

I’m not a fan of D-STAR audio. P-25 is a little different, but I don’t find it better. D-STAR appears to have better signal-to-noise. P-25 seems to have a persistent background burble, while D-STAR is pretty much dead silent between words. The fidelity of both is poor “communications quality” and fatiguing for long-term listening.

True, much of the commercial equipment is more durable than most ham equipment. But hams doing Emcomm don’t universally use commercial equipment in the analog world. They use ham equipment (though i see a lot of commercial equipment used on the ham bands in Emcomm command center vehicles).

“In many cases, APCO25 gear can do both analog and digital. DSTAR repeaters are digital only. …it’s a nice fall back option to have there. AKA, flexibility.”

The fall-back is a completely separate, redundant analog repeater. Nobody’s advocating an all-D-STAR Emcomm solution.

“APCO is a public safety group that defined the standard, a standard created with a lot of thought towards the future…”

P-25 is about to go through a complete protocol revision, to Phase 2. This is completely incompatible with the first generation of P-25 equipment (though some of that equipment can be upgraded). Will the amateur community be “Phase 1″ for years, or upgrade to “Phase 2″?

Ham use of P-25 was expedited by the appearance of inexpensive surplus equipment as the first wave of equipment reached its 10 year life cycle and was replaced (hence the “all Motorola” impression, as it took time for other manufacturers to join the P-25 bandwagon, so most surplus stuff was Motorola. Sound familiar, as with ICOM and D-STAR?). It’ll be some time before we see affordable Phase 2 hardware, but that’s where the compatibility will be, isn’t it?

“If they wanted a data layer, then strap it on top of an existing standard and allow backward compatibility to APCO25. This layer should be completely open and extensible. Let us hams do what we used to do best…innovate.”

Innovation and compatibility are often at cross purposes, and we see that in the expensive and sometimes painful transitions when the advances of innovation are just too great to pass up any more for the sake of keeping everything working the way it was. That’s happening faster and faster today.

D-STAR and P-25 both have this problem. At some point, you have to say “this is what we’ll use” for the next period of time, and not pile on every update that comes from the design lab. But some day, D-STAR – if it is successful – will have to do its own “Phase 2.” The DVSI guy I talked to said they weren’t shutting down their design lab.

“From what I gather from my travels and talking with other repeater sysops, most hams going digital are deploying P25 commercial grade gear. These P25 repeaters are seeing more interest/usage than comparable DSTAR repeater systems.”

Can you back this up? From everything I’ve seen, D-STAR is growing quickly with new repeaters and a network structure, while P-25 is plodding along with stand-alone repeaters.

“Both DSTAR and APCO25 are interesting technologies with pros and cons both ways. In the end things will have to stand on their own merit, not hype. I predict ICOM and the DSTAR folks are going to regret their choices.”

In my QST article “Operating D-STAR” – published an eon ago (Sept. 2007) and written months before that – I couldn’t make a prediction. And I still can’t. Ham radio doesn’t have an APCO to lock in a standard (and then update it 10 years later). I do see enthusiasm for D-STAR, but it is still very much a niche, with a small percentage of hams participating. But the progress has been impressive so far. ICOM has made a huge commitment (and Jeff castigates them for promoting it). They’ve got a lot at stake, but they can’t force us to adopt it. If somebody’s going to come along with something better, though, they need to do it soon.

Lack of P-25 compatibility may be a disadvantage. With analog FM, we could hear the public safety systems on our receivers, and use that equipment on ham frequencies (legally). That advantage diminished with the advent of 800 MHz and trunking. Our radios couldn’t track the trunking systems, and their radios didn’t operate in the ham bands any more.

D-STAR does have unique advantages, like the flexibility of the embedded, raw ASCII data stream, the relatively simple networking scheme, and the fact that it is incorporated in the frequency agile, flexible amateur radio equipment that most of us prefer.

I own four D-STAR radios, and one P-25 handheld (that I can’t program myself). I guess I’ve cast my lot – it would be expensive to adopt something all-new. But I know I’m taking that risk.

73,
Gary KN4AQ
Amateur Radio//Video News

9. k9zw - 26 - August - 2008
10. wa4zko - 15 - September - 2008

NTIA/IAFC report reveals serious fire service concerns with digital-radio systems:

http://wa4zko.wordpress.com/2008/09/10/ntiaiafc-report-reveals-serious-fire-service-concerns-with-digital-radio-systems/

FWIW

Jeff
WA4ZKO

11. Alan N3IMU - 28 - September - 2008

Why don’t we just call this what it is: a good old-fashioned standards war. Icom is pushing D-Star, some enthusiasts are pushing P25. The arguments about interoperability and which system is more “open” are red herrings; this is really about what system hams are going to use in the future. As the long and storied history of previous standards wars shows, that decision will ultimately be non-rational, and at this point it’s completely unpredictable.

If you buy into one system or the other right now, you could be the first on your block to use the technology of the future, or you could be flushing your money down the toilet. D-Star could be the next Blu-Ray, or it could be the next HD-DVD. I’m currently shopping for a VHF/UHF mobile rig, and after reading several pages of these debates on different sites, I think I’ve made my choice: FM.

12. wa4zko - 27 - August - 2009

“The arguments about interoperability and which system is more “open” are red herrings; this is really about what system hams are going to use in the future.”

I would have to say that interoperability is coming up more and more in the world of EMCOMM and I stand behind my opinion (that’s all it is, an opinion from someone with a public safety and ham radio background) that pursuing another digital voice standard that is NOT compatible with P25 is a mistake. Either that or we better come up with a better belt to hold all the radios you’ll have to carry to be effective in a major emergency. A mistake we will eventually regret if the hobby (as we know it today) lasts long enough.

Again, just my opinions.

13. Mike A9VI - 14 - December - 2011

Guys, forget the D-Star. Choose DMR. DMR has over a half dozen manufacturers, is cost competitive, and the MOTOTRBO stuff, in particular has outstanding performance. Not to mention, you get TWO digital voice channels from one repeater in HALF the channel bandwidth of an analog repeater. Plus, yes, there is GOOD diagnostic software out there.

http://dmr-marc.net


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