D-Star in Dixie
Okay, this is not strictly SDR, but this site is dedicated to discussing the latest and interesting technologies that are being used in Amateur Radio. Like a lot of hams, I had sort of dismissed D-Star as an expensive niche product. Last field day, a ham friend on mine mentioned that a new D-Star repeater had been brought up in the area. After the discussion, I thought I would take a second look at D-Star. I was surprised to see so many D-Star repeaters had sprang up in Georgia (about 26 and still growing). As a matter of fact, D-Star repeaters are popping up like weeds in the Southeast. Other areas of the country are also seeing growth in D-Star repeaters. I was also quite amazed to see that there were about 18,000 registered D-Star users worldwide . If you want to see the the statistics of how quickly D-Star is growing, take a look at the D-StarUsers.org Watch D-Star Grow page. The daily number of new users joining the network is pretty eye-opening.
After some time spent researching the technology, I decided to take the plunge. So, I thought I would jot down my experiences with D-star from the “newbie” perspective and dispel a few myths if you are considering getting into D-Star. I had the opportunity to test three pieces of D-Star hardware for this article. The Icom ID-880H mobile, Icom ID-80AD HT, and the DVAP Dongle. I will be posting my impressions of the hardware in future articles, but for this article I will primarily focus on D-Star.
Getting on D-Star
One reasonably inexpensive approach to get on D-Star if you have poor or no access to a D-Star repeater is the DV-Dongle. The DV-Dongle is a USB device that plugs into your computer and gives you access to the D-Star network using the computers speaker and microphone. Before you can use the DV-Dongle you will have to register as a D-star user on the D-Star network with a system admin of your nearest D-Star repeater.
The registration is free.(Some repeater owners don’t take registrations, so you may have to register on another D-Star repeater in your area). You only need to register once to have access to the D-Star network. The process can be a bit slow depending on the sys admin, but don’t register on multiple repeaters as this may cause you additional issues. Your better off to be patient or email the system admin if you don’t hear from them in a reasonable time. To register go to the D-StarUsers site Repeater page and look up the repeaters nearest you. By clicking on the link to the repeater you will see if they have a Gateway Registration link. Follow the link and follow the registration instructions. You do not have to register to use your local repeater, for local conversations using a D-Star radio. However, your repeater may be attached to a D-Star Gateway linking it to another repeater or to a Reflector that has multiple repeaters linked. You won’t be able to use the Gateway without D-Star registration.
I hear a lot of DV-Dongles being used on D-star, so they are apparently pretty popular. Some hams use these as their primary D-star access devices and others as a secondary device for use at home in addition to an HT or mobile D-Star radio. The DV-Dongle runs about $200.
D-Star Equipment is Expensive
Yes and no. This one you hear a lot. I have already discussed the DV Dongle as an inexpensive way of getting involved with D-Star. Since I have a D-Star repeater in my area, I decided not to use the D-Star Dongle, but the RF approach to access the repeater. First off all, my QTH is in a repeater unfriendly location. This primarily due to being located in a low spot with lots off trees and not being able to use outside antennas. The D-Star repeater is located approximately 30 miles away from my QTH. Since, I did not have much luck using the analog repeaters in my area due to my location, I wasn’t sure how accessing the D-Star repeater was going to work out. My understanding of D-star range was that it was about the same as analog FM (I would say that it is a little shorter because if you don’t get a good signal to the radio, the digital decoder can’t clearly decode the signal).
First of all, when you start looking at D-Star radios, your choices are pretty much limited to Icom. There has been some erroneous information floating around that D-Star is a proprietary format owned by Icom. This is not true. There is no reason that other radio manufacturers can’t produce radios incorporating D-Star. With D-Star becoming so popular that might eventually happen, but for now it’s primarily Icom. I thought I would start my testing with the Icom ID-880H mobile attached to my attic VHF/UHF vertical and see how things went. As far as cost goes for a D-Star mobile, the Icom ID-880H is right in the middle of the price range for VHF / UHF mobile rigs from all vendors. There are 6 VHF /UHF rigs cheaper (some of these are only slightly cheaper at that) and 5 rigs more expensive. The most expensive Icom D-Star rig is the IC 2820 with the optional D-Star board installed (also the most expensive VHF /UHF rig). You can get a D-Star rig a little cheaper by getting a 2 Meter IC-2200H and adding the UT-118 D-Star board. However, I feel that the ID-880H offers a better value for a little more. So in the mobile category D-Star is not really that much more expensive than other VHF / UHF radios.
However, D-Star HTs is where D-Star can cost you a bit more than other UHF / VHF HTs. The D-Star HTs are at the top of the price list. There are two D-Star capable HTs from Icom, the IC-80AD (which I tested) and the IC-92AD. The basic difference between the IC-80AD and the IC-92AD is that the IC-80AD is a VHF / UHF one band at a time radio and the IC-92AD has dual band receive via a sub receiver. Again, you buy an inexpensive 2 meter HT from Icom and add the optional D-Star board, but not a really good value when compared to the other Icom D-Star HTs. Icom has announced a single band UHF single band HT with built in GPS coming out. However, no price has been announced yet, but it could be cheaper.
D-Star Radios are Hard to Program
Not hard just different. Programming analog repeaters is the same as always. Programming D-Star does require a slight learning curve. I won’tgo into a lot of detail here, there are articles on the web that explain it much better than I can. I found this tutorial was actually pretty easy to understand. The real magic happens in the MYCALL discussion, so pay attention. Most of the linking functions of D-Star happens in this area. If you plan to just program the radio for your local FM and D-Star repeaters it is pretty easy to do by hand. If you are going to program in lots of repeaters, Public Service frequencies, and MYCALLs, I would suggest you spring for the USB programming cable and software from RT Systems. Even though you get free programming software from Icom, I feel the RT Systems software is better and easier.
There is No One to Talk To
This myth is not even close. While it may be true that your local D-Star repeater is not terribly busy, link to one of the D-Star Reflectors and that all changes. The Southeast Reflector REF030C stays pretty active with users from all over the Southeast and the world. The reflectors typically are grouped by geographic regions or function such as weather nets. D-Star also allows you to send data with programs such as D-Rats, so there are Reflectors dedicated to data. D-Star gives you the capability to talk with hams across town and across the word. Here is a list of the various D-Star Reflectors available. D-Star is usually compared to Echolink which is a voice over ip ham radio application. Even though Echolink can be setup for mobile access with the proper hardware installed at the repeater or the users station, it is more typically used with a computer. In comparison, D-Star can be more easily used either way especially if you have access to a local D-Star repeater. D-Star appears set to become the standard for Amateur Radio digital communications. D-Star can also perform similar functions as APRS when equipped with a GPS receiver. Icom sells GPS equipped mikes or you can roll your own GPS interface.
So, How Did it Work Out?
In a word great! I love the noise free reception of digital radio (zero noise floor). The only issues I noticed depended on the radio reception and the equipment being used to transmit. The audio can sound a little synthetic at times. The audio overall was very good the majority of the time. Mal-adjusted DV Dongles audio could be a little low at times. Weak signals will cause packet loss that will cause the audio to degrade into gibberish (also known as R2D2). I noticed this more when mobile units got into spotty repeater coverage areas. The mobile rig let me hit the local D-Star repeater with 25 watts from my attic antenna with good reception and good audio. The HT was another story. Cranked up at 5 watts it would not hit the repeater on VHF and a little bit on UHF. The UHF access was not good enough to be reliable. Our local repeater usually stays linked to REF30C on VHF and I could not reliably hear the transmissions on VHF. Installing a higher gain whip did help with receive, but not much. I guess I could link to REF30C on UHF and hear it, but I hate to mess with the configuration of the repeater. There is a good deal of traffic on REF30C, so there is plenty to listen to and talk to. So, in my location the mobile worked great, but the HT not very well.
Enter the DVAP Dongle
I really wanted to use the HT to keep up with the D-Star activity, but the poor reception in my area made that impossible. I did a little research and found out there was a solution, the DVAP Dongle. Okay, I was curious so I arranged to try one out. The DVAP Dongle is different from the DV Dongle. The DVAP Dongle when connected to a computer creates a D-Star “Hot Spot” in and around your house using 100 milliwatts on VHF. It is pretty much a mini D-star repeater. It uses your computer and internet connection to allow you to link to a D-star repeater or Reflector. You still need to have a D-Star capable radio to use it since it doesn’t have a decoder / encoder chip built in like the DV Dongle does. It works great. I can now have no problem using the HT around the house or even outside the house (way outside). I have it connected to a cheapie 800Mhz netbook that runs 24 / 7 on my wireless network. The DVAP Dongle doesn’t require much computer horsepower to run and the netbook doesn’t use much power. I see a lot of these in use on D-Star. I have even heard some hams using them as they traveled. They are connecting them to a laptop in their vehicle that has access to 3G or 4G data services via a network card or a wifi hotspot through their cell phone. Cool! Others take the DVAP Dongle with them when they travel so they can use their D-Star radios where there are no repeaters by using the laptop with WiFi or 3G / 4G data services. Another thing I like about the DVAP Dongle is that you can use it to link to another repeater or reflector independent of your local repeater. In other words if you want to link to an Italian reflector to brush up on your Italian, you won’t be bothering the users of your local D-Star repeater. Another nice benefit is that you can set up your HT to scan both your local repeater output and the DVAP Dongles output. This allows you to keep up with activity on both your local repeater and whatever you linked the DVAP Dongle to.
Conclusion and Final Impressions
I will have to say that D-star is now pretty cool and it has certainly allowed me to enjoy VHF / UHF more than I have in the last few years. I highly recommend it. It is not as expensive as you might think. The programming is not that hard if you are willing to spend a little time learning something new. The DV Dongle is a great way to tip your toe into the D-Star waters at a very reasonable price. There is certainly plenty of users to listen to and talk to. The other thing I noticed, is that some areas are setting up D-Star to be used for emergency communications use. This is certainly the case in Georgia. Almost the entire state is linked by D-Star repeaters. There has been some discussion as to how reliable D-Star is versus analog FM repeater for emergency communications use. In my opinion D-Star has tremendous potential for emergency communications. I am sure we will see improvements in reliability and certainly more hams are moving to D-Star everyday. I would have to say that D-Star has finally become a fairly mature, useful, and fun technology.
and a Big Shout Out to the local hams who helped me out with learning about D-Star.
Stay tuned for more impressions of the gear I am using!