Rick,

What do you consider that has changed that will cause ICOM to "corner 
the market" on D-Star? They have spent rather large amounts of money 
developing and then promoting this approach to digital for many years 
now. Maybe even more than any other company selling into the amateur 
radio market with amateur only products. This is not new technology 
having been begun by JARL with some kind of arrangement with the 
Japanese government in the late 1990's.Even after all these years, the 
adoption rate seems modest, but it is growing in some areas, but no 
other manufacturer is competing in the DStar market, which should tell 
you something. One claim was that Kenwood had shown and was going to 
sell a Kenwood labelled ICOM D-Star unit, but I am not sure if this is 
going to happen.

Meanwhile, with minimal (no?) advertising the amateur publications, some 
radio amateurs are moving toward P-25 and now MOTOTRBO. One of the 
problems with digital radio is that they are not able to interoperate 
with each other and therefore form separate islands of compatibility. 
This is not as much a problem when a local unit of government moves in 
this direction since they are more self contained (however, outside help 
is a problem with communication resources). But amateur radio crosses 
political boundaries so it is a different kind of communications 
"service," where interoperability is much more important. Imagine if 
there were different brands or systems of FM or SSB equipment sold on 
the amateur market that did not work with one another.

The article in QST was very well balanced and it did point out some of 
the pitfalls as well as the advantages. What concerns me the most about 
the digital interest from radio amateurs in VHF and higher frequencies 
is that it is mostly being done because it is *digital,* and not so much 
because of the advantages over existing modes. You can see this with the 
comments some have made about "legacy" modes. For any new mode to 
succeed, it must offer benefits above what you now have in order for it 
to have wide adoption.

Ironically, one of the D-Star benefits is the non radio part whereby you 
can connect systems together via the internet. Although I admit that 
some of this is done now with IRLP and Echolink at very low cost, D-Star 
has more connection technology that might be useful for traveling hams 
who want to connect back to their home area or hams from their home area 
being able to find the travelling ham, assuming that you have D-Star 
systems ubiquitously located at some time in the future.

It seems to me that D-Star's strongest point's are that it:

- has a spectrum conserving narrow bandwidth of 6.25 kHz. This is an 
advantage over other digital systems, and certainly over FM (but not SSB 
which is much narrower). At this time, amateur radio is not under much 
pressure to go to narrower modes. In fact, it is the recipient of older 
FM systems that became available from government sources that were 
forced by the FCC to move toward narrower modes.

- is more open (although apparently not quite as open as we first had 
thought), than the commercial systems which are likely totally 
proprietary. The opendstar.org group may eventually give us a better 
understanding of how it works. One other group tried, but failed to make 
an open hardware solution.

- will be lower cost than commercial systems since it does not require 
the higher standards of commercial equipment design mandates.

The downsides are not insignificant though:

- very poor quality audio compared to FM unless you are in a fringe 
area. This is something that would have to drastically improve for me to 
have any interest in the mode at this time.

- the cost is higher, especially for HT's where the price is essentially 
double, or even more than double the cost of an FM HT.

- the data throughput is unacceptable for a new technology and is about 
as slow or even slower than the very oldest 1200 baud packet on the data 
side.

It may be possible to eventually come up with an improved D-Star that 
would use the entire bandwidth of the 2 meter/440 designs for voice, 
when you operated voice, and data, when you operated data. It seems to 
me that this would help to address some of the design shortcomings.

73,

Rick, KV9U


r_lwesterfield wrote:
>
> There is a very good article about D-star in the September QST. And 
> from the looks of it, Icom is poised to corner this market in fairly 
> short order. It is selling HT’s, mobile rigs and repeater equipment 
> where no other manufacturer has stepped up to the plate yet. The 
> article in QST is fair and balanced and does mention P-25 (the 
> competing protocol standard) but nobody is selling amateur equipment 
> that supports it. You have to convert commercial gear if you want to 
> play with P-25.
>
> So look up the article when it becomes available on the ARRL web site. 
> I know that I learned a lot and now wish I had the cash to put up a 
> D-star repeater on 70 cm or higher here in NW Louisiana.
>
> Rick – KH2DF
>


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