Ham Radio Forum

Jan van Vugt

The D-STAR digital transceiver is a development of the JARL (Japan Amateur Radio League) to answer the needs of hams for a true digital audio amateur radio system. D-STAR is an open protocol that is owned by the JARL and can be used by any ham radio manufacturer on their equipment. ICOM is the first manufacturer to build radios with this protocol, but they are not the owner of the protocol.

The Japanese Government, through its agencies, has spent many millions of dollars since 1998, to bring D-STAR to where it is today. See http://www.icomamerica.com/d-star/DStarHistory.asp for more details.

A D-STAR ham radio meets the legal requirements of the FCC and Industry Canada by automatically attaching the stations call sign to every packet that is transmitted. The Amateur Radio Operator can see, on the display of his radio, whose radio is being used, (except on the ICOM IC-2200H) even if the operator is using a different call sign. D-STAR allows for up to eight characters to be programmed in to the radio to identify the station.

It is now up to ham radio operators to make D-STAR a success by supporting the manufactures that build this equipment for us. The possibilities of D-STAR are only limited by your imagination. See my other article (D-STAR – The Most Exciting New Mode), at http://www.eham.net/forums/Digital/2319 . Ask your clubs elected officials to get in touch with repeater manufactures and encourage them to make D-STAR a priority. The sooner that we get a network of D-STAR repeaters in place, the sooner we will be able to enjoy the full capabilities of the D-STAR Internet Gateway.

Ham buddies or families anywhere on the globe will be able to keep in touch with each other, with little or no effort on their behalf. Once they have programmed their radio, they only have to turn to the correct memory slot and make the call. With “call sign to call sign” calling, the D-STAR ham radio software will automatically connect two D-STAR repeaters together as long as both radios have made their presence known by using the repeater.

D-STAR is 21st century technology. It is ours to build on. What new ideas can you come up with for the possibilities of D-STAR?
_________________
Jan van Vugt - VE7TKO
"I am 100% sold on D-STAR"
I Monitor D-STAR DV on 145.600 MHz
Jan - The D-STAR Man

oldretiredguy23 · Guest

Dstar requires an exspensive backbone. Most hams in the US do have the money to pay for it. DSTAR in theory works great. The problem ham radio here in the states is slowly dying, becuae folks under thirty are not getting into the hobbie anymore.

Jan van Vugt · Posted: Sat Nov 12, 2005 4:20 am Post subject: Re: I do not agree

DSTAR · Guest

If you try to talk through an analog repeater, in digital mode, it will not work. The repeater must be able to receive a digital carrier and re-broadcast a digital carrier.

Since a digital carrier is different than an analog carrier, a non-digital radio can not re-broadcast the digital carrier. It's not just digital data, it's an actual digital signal. If you try to transmit, in digital mode, into an analog repeater, all the analog radios on the repeater will simply hear white noise and a digital radio listening will hear nothing. The digital radio will see activity on the signal strength meter, as would be normal when there is analog activity on the frequency.

_____________________________

Kevin McClinton, W7JRL
Amateur Technical Trainer

ICOM America, Inc.
2380 116th Ave. NE
Bellevue, WA 98004
Ph. (425) 454-7619
Fax (425) 637-8417
www.icomamerica.com

DSTAR · Guest

The answer is, NO it will not work.

The reason is simple, the modulation scheme is not compatible, nor is the repeaters circuitry.

In a typical analog repeater, an FM demodulator is used to demodulate the FM signal, effectively "decoding" the voice signal imposed upon the carrier, by way of Frequency Modulation. The analog repeater then takes the analog audio, and passes it to the repeaters transmitter, where it is "re-encoded", by the FM modulator and sent over the air.

In a D-STAR repeater, an IQ demodulator is used, to "decode" the data imposed upon the carrier, by way of Gaussian Minimum Shift Keying. Once the digital signal, effectively ones and zeros, is extracted, it is buffered and regenerated. The regenerated signal is sent to the transmitter where it is "re-encoded" and sent out over the air.

As you can see, the operation is similar, up to the point where the signal is received, by the repeater, but after that, the process, and type of signal (one being audio and the other be data ones and zeros) is very different.

Any type of digital system, that uses tones, or audio, to represent data, can be passed through an analog repeater, because that’s what analog repeaters pass, Audio. Not all analog repeaters will pass that digital signal well, since there can be level and fidelity issues, but it should work. That’s also why D-STAR a "true" digital system will not go through any analog repeater.

_____________________________

Matthew F. Yellen K7DN
Systems Engineer
Report msg +5pts

Paul Pollock · Joined: 24 Nov 2006 Posts: 3

I must tell you, after talking to a Icom rep (at ICOM America) about D-Star, and getting few good answers to my questions, I must tell you this is going to be an enourmous boondoggle. For one thing, there is no question of D-Stars' increased cost, for zero voice communications gain.

For one thing, while performance for digital radio is quite good, at normal signal levels, poor signal levels begin to show real problems. Digital voice either works or it doesn't, and the drop out generally occurs sooner than analog total unintelligability. Marginal signal for Digital, is normally quite readible at the same level on analog (if you allow the same amount of noise to be present that might be present in a SSB shortwave signal). This is not an exageration, it is simple fact.

On average, D-Star voice over 2-meters (the cheapest of the bands for performance/dollar) is more than 100% more expensive to install than a good quality analog 2-meter repeater. This is no joke, for the average repeater club. I can read a price list from any retailer for D-Star. Just for a 2-meter repeater requires at least three(3) basic components, totaling more than $4000, and we haven't even gotten to power supplies, duplexers and antennas.

A good Hamtronics repeater is less than $1600 for the basic chassis. And they've got hardware in orbit. Trying to do D-Star in space will require much more cabinet space, power and weight.

The other major problem is the vocoder codec is proprietary, requiring (some time in the future, you know, when JARL figures there's real money in it) a use license for each radio maker/user. Like P-25 (a competing vocoder) the license is beyond the price range of even the largest Ham club. What this means to the average user is that there is no way a Ham can design/build his own D-Star hardware. Some people are still building their own repeater hardware (Hamtronics still supplies receiver/transmitter kits for repeaters, and they are the best analog repeater RF equipment available [don't get me wrong, I don't own any Hamtronics]). This kind of hands-on experience will be impossible via D-Star. After all, people are still building transcievers for VHF, and Ten-Tec still produces the T-Kit 1220 2-meter transceiver. I built one of these and it works quite well, into all of the most popular repeaters in my area.

I like toys, I even like expensive toys. But D-Star is a STUPID expensive toy, that will tend to destroy more of VHF ham radio, because of its' proprietary nature. Ham Radio is about radio communications, not sending voice by any means possible.
IRLP and like systems are NOT Ham Radio expanded by Internet, it is Internet with a radio gateway. And D-Star is not radio expanded by digital, it is contract digital transcievers/repeaters paid for by Amatuers. Commercial Radio would love to have such a technological diversion.

D-Star is a long way from a good idea.
_________________
Paul Pollock
KD7BWB
D-Star is an expensive joke!

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

Paul, you have made the point quite well. It is cheaper to get a used hand me down VHF anaolg repeater from the public service agency then it is buy a DSTAR reapeter.

How many clubs have the budget to buy a DSTAR system. Secondly who wants wants to obsolete there current working anolog equipment and throw it away.

Paul Pollock · Joined: 24 Nov 2006 Posts: 3

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

Here is a DSTAR SNIP from:

http://www.northwestradio.com/bbs/viewtopic.php?t=1203

The D-Star system is a nice arrangement. Unfortunately it's out of bounds price wise for most in the area allowing it's implimentation to stagnate. It's also a proprietary format which closes out others from developing further to reduce the over all cost.
Maybe Icom will re-evalute this in the future and provide a better cost effective means for digital communications.

73's de KG7HQ
_________________
Thank You,

Michael
ARS - KG7HQ
Assistant Director/Technical Specilist
Northwest Division
ARRL
kg7hq@arrl.net
http://www.wetnet.net/~kg7hq

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

It's too bad that Icom tried to monopolize the market in this area instead of making it open source. I recently saw where they upgraded the firmware for addtional and improved features. But since the price is still up there, most hams will just thumb their nose at it and maintain normal FM communications with the continuious experimentation using sound card interfaced systems for digital support.
I'm seeing the Terminal Node Controller (TNC) communities take a hit as more look for a less expensive means of facilitating digital comms.
Open source software defined systems are the new rage... I hope the big "3" amateur radio companies pay attention and get invovled soon.

73's
_________________
Thank You,

Michael
ARS - KG7HQ
Assistant Director/Technical Specilist
Northwest Division
ARRL
kg7hq@arrl.net
http://www.wetnet.net/~kg7hq

Paul Pollock · Joined: 24 Nov 2006 Posts: 3

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

There are two pieces of equipment you would need from Icom to setup a 2 meter D-STAR repeater. You would need the RP2000V which is the repeater and the RP2C which is the controller.

Ham Radio Outlet has the RP2000V listed for $1399.95 and the RP2C is listed for $1459.99.

You will also need antennas, feedline and probably a duplexer to complete the system but Icom does not manufacture and sell these items.

Brian Cheeseman, KE7DIQ
Technical Support

Icom America, Inc.
2380 116th Ave N.E.
Bellevue, WA 98004
Phone: 425-454-7619
Fax: 425-637-8417

kc7qdo · Joined: 23 Jan 2007 Posts: 1

Hmm this is a interesting post. But now that the real data is coming out about D Star makes me not want to try this mode.

The possibilities of this mode are endless granted. But with the costs and ever increasing reports of needing higher signal levels to work each other does not appeal to me.

I think anything digital for ham radio is going to need to be able to work with analog equipment like that digital voice modem that is available for HF operators even though it costs allot.

I am going to keep my analog gear because it works and it will be around for a long time to come. So my FM gear will work with FM gear regardless of manufacturer.

I am glad this information is coming out now so I don't waste my money on a mode that is doomed to go the way of Packard Bell and the Commodore computer.

Thank you for the real data on this mode. Since this data was so hush hush till recently. Crying or Very sad

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

That what it is about money. Money that ham will have to pay to the manufacturers to throw away good working equipment. So actually they are paying twice.

Radio_Girl · Joined: 26 Feb 2007 Posts: 10

D-STAR is a great tool, even though it can be really expensive to use effectively.

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Kenwood TS-480HX / TS-480SAT - TS-480HX/TS-480SAT HF/50MHz All-Mode Transceiver by Kenwood Communications Division