Ham Radio Forum

Jan van Vugt

There is a new webpage called “D-STAR for the Second Century of Amateur Radio.” You will find it at: http://www.icomamerica.com/amateur/dstar/ . I think that most hams will appreciate this document because it is not an “ICOM Only” document. It covers all aspects of JARL’s D-STAR, including home brewed repeaters, Digital Voice (DV) and Digital Data (DD). There is already a home brewed D-Star repeater in Portland Oregon.

I only wish that the complete document were available in PDF format, so that any interested ham could download it for easy reference.
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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

ICOM Snip · 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
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will not work
Guest

20 Nov 2005 1:17 Re: Jan van Vugt – VE7TKO – on the Icom IC-V82 D-STAR Ham Ra

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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.

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Matthew F. Yellen K7DN
Systems Engineer

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

ICOM actually takes up more band width. Thank standard anolog.

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

I'm sorry old man, but I judge these things strictly by actual results, not by the fact that somebody does or does not promote whatever it may be, hoping that by doing so their investment will not be wasted.

I noted how you went on at great length about how D-Star *can* be used with radio but in the end, you had to admit that the Internet alternative is pretty much inevitable if it is to "perform" at a reasonable price and level of difficulty.

My way of looking at amateur radio applications is that if you have to put aside the use of radio in order to make it "perform", then it has no creditable performance at all as an amateur radio application.

D-Star, like Packet Radio and other digital ham radio setups, is subject to the same old laws of physics. You can get more speed at higher frequencies, where the expense and complexity rises in a geometric progression. Long before you get the kind of performance that is being hyped, those factors go way beyond what the great majority of amateurs would ever consider. - So you end up copping out on ham radio and hooking your new miracle digital setup to the Internet instead.

I'm only really interested in digital amateur radio, and if you stick with that, D-Star does nothing that Packet Radio cannot do far cheaper and with a good deal more flexibility.

My feeling is that you've been sold a bill of goods and hope to have company in this, so you won't feel foolish for having paid so much extra only to end up with yet another digital system that is subject to the same laws of physics as all of the rest.

I would wish you luck in your promotional endeavor, except for the fact that it would mean that other innocent hams would have been hoodwinked and ripped off as well.

If I were you I would ask for my money back... I sure would not try to save face by "promoting" the same misfortune upon my fellow hams.

The really good stuff does not require any significant promotion, in my experience.

No hard feelings OM, and there is certainly nothing personal to it, but this how I see it. I am well known for calling them as I see them, so don't let my opinion upset you. - Just see if there's any way you can get your money back.

Charles Brabham, N5PVL

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

KD7BWB says:

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.
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Paul Pollock
KD7BWB
D-Star is an expensive joke!

HAM RADIO STUFFING SAYS:

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.

KD7BWB SAYS:
It is cheaper to buy a BRAND NEW analog repeater, than a D-Star product. And that's the point. I haven't seen a single NEW repeater that even gets close to the cost of a D-Star repeater (althoug some can approach $3000).

Don't get me wrong, Digital audio radio is coming. I am especially excited by the notion of digital voice radios for shortwave ham bands. This doesn't work very well when you operate digital audio with an analog radio; but a specialized digital radio would work quite well.
Alinco already has a protocol that works and is built into some of their VHF/UHF radios, it also works fine through the analog repeaters as long as you still send the PL-Tones properly. But these radios really shine between radios simplex.

D-Star is mutually exclusive. It requires its' own repeaters, and analog radios cannot travel via D-Star repeaters, while D-Star radios cannot use an Analog repeater. That's how picky they are. I think there is room for digital audio, but making them inoperative with analog repeaters makes the whole proposition very expensive and time consuming. It also means there will be multiple effort expended (one an already present system of analog repeaters, and the other will be the growth of a D-Star system; fighting over the same spectrum). This is NOT going to be a pretty picture.

I live in Arizona, and there is already over 100 repeaters in this state. This means there is two problems, frequency spectrum AND places to put repeaters. Many Amatuer repeaters in Arizona have to share physical space with public services, which brings into play jurisdiction problems with access to facilities that are also shared with government. Government facilities managers are going to have very little sympathy for Amatuers wanted to install another system of repeaters for the same radio spectrum with zero voice advantage.

In my view, the digital data advantages require an enourmous commitment of resources that have absolutely nothing to do with Amatuer Radio. Facility conveniences are a nice idea, but cellphone already supplies them already, and none are required for emergency situations. They are all fun stuff that requires a lot of Human hand-holding. Cellphone companies already has commercial and manpower resources to provide these services. Re-inventing this wheel misses the point of Amatuer Radio. We are precluded from commercial investment or profit. And carrying out these features on a day-to-day basis is going to make Amatuer Radio look more and more like something that needs FCC commercial service supervision.

What Price Glory?

Thanks for your input, it was a great post <grin>!
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Paul Pollock
KD7BWB
D-Star is an expensive joke!

KG7HQ SAYS:

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
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Thank You,

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

KG7HQ SAY MORE:
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

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

Radio_Girl · Joined: 26 Feb 2007 Posts: 10

I'm not particularly fond of ICOM, as I can never get good service from them.

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

hamradiostuffing · Joined: 02 Oct 2005 Posts: 18

by K5ADF on March 25, 2007 I will try posting my comments on here since they were removed from the product review section. It seems as though I made some ICOM lovers unhappy with my opinion.

ICOM is pushing D-STAR. They have several transceivers on the market including the IC91, which I own. I am happy with it and the price I paid. I was awaiting the IC2820 D-STAR dual band radio with my money in my hand. I had talked to the ICOM representative at HamCation in Orlando in February. Even though I have never purchased a new product before it had been on the market for at least six months, I was ready to submit my order.

Then it happened. ICOM announced that it was ready to ship. I went immediately to my local dealer to place my order. What a shock to say the least. The IC2820H is priced at $650!!! That would not be too bad IF it included D-STAR. But it does not. That is an additional $300 making the total price with D-STAR $950!! I guess ICOM does not really plan to sell many of these radios.

The Yaesu FT8800 sells for $375, $275 less than the base IC2820H making the IC2820H almost twice the price as the Yaesu. The IC2720H, which the IC2820H replaces, is rated by 159 eham users as 3.3 with a lot of complaints about the final. The FT8800R is rated by 107 users as 4.5! It seems as though the FT8800R users are a much happier lot.

Therefore not only would I be paying a $275 premium for the basic rig but the radio it replaces leaves much to be desired. The rating difference is why I have FT8800R rigs in both my vehicles. I was ready to bite the bullet and hope that ICOM had solved their VHF/UHF mobile problems so that I could have a D-STAR mobile. Yes, I know about the ID800. I should be grateful however since now I will not be the one to find out the rig is perhaps no better than the one it replaces in terms of reliability.

I love my ICOM 956Pro and would not trade it.

Too bad ICOM - you really blew this one!!