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FYI : Digital vs Analog VHF/UHF

An article that may have relevance for You.

(ripped from Vienna Wireless Society (Fairfax, VA))

Let’s start out with making the choice between analog and digital radios:

Any digital voice radio you’re going to buy will also support analog operation. So, if you choose an analog-only radio, you’re limiting yourself to only analog. If you go with a digital voice radio, you’re not locking yourself out from analog simplex or repeater operations.

I own radios that run all three major digital voice modes: D-STAR, Fusion/C4FM, and DMR. After using them all, for quite a while now, my mode of choice is D-STAR. I’m going to try to give a very brief rundown of my reasoning, hopefully not turning into a treatise.

 

DMR   is highly deployed in the NoVA/DC/MD area. If you want a radio that you program once (probably using someone else’s configuration file, or “code plug”), that has all of the local repeaters, etc. included, you may want DMR. I have not yet done the research about DMR coverage in the other areas you mentioned, or in the areas between those areas (if you’ll be on the road), but you’ll need to either reprogram your radio for each area, or create a relatedly large and possibly cumbersome custom code plug to support operating in multiple areas. DMR radios are very easy to operate once you get all of this programming done, but the programming task can be a lot more work than many hams are able or willing to do. DMR requires registering your radio to get a “radio ID”. When I registered my AnyTone 878 about a year ago, I believe it took a day or two to get my ID. Some of the more recently released DMR radios have an option to maintain a local mapping of radio ID to callsign/operator name, which is a nice feature, except you have to keep downloading the updated list and updating your radio to keep up with the new ops, if you care to use that feature.

 
 
Fusion/C4FM, in my opinion, is the easiest option to use “out of the box”, and has the best sounding voice/signal quality. The initial minimal programming of a brand-new Fusion radio involves entering your callsign, which the radio will prompt you to do when you initially power it on. Of course, you also need to program in local area repeaters, not much differently than you would with an analog radio. Fusion repeaters are designed to work in a combination of analog and digital. Using an internet-connected (aka “WiRES-X”) Fusion repeater to connect to different “reflectors” (virtual chat rooms created by linking multiple repeaters together via the internet) is done through a menu system on the radio, which is pretty easy to do once you learn the menu interface. Fusion’s downside (in most areas) is that it is not as widely available as DMR or D-STAR in most areas. Fusion radios do not require any form of registration, so you can be up and running on Fusion repeaters minutes after taking your new Yaesu radio out of the box, after just entering your callsign and configuring the radio to be able to reach the nearest repeater. Fusion sends operator information with each transmission – no need to keep updating a callsign list on your radio.
 
 
D-STAR involves a little bit of learning, but once you’re up and running with it, it is relatively easy to use. The primary method of using D-STAR involves the use of reflectors (such as with Fusion). From your D-STAR radio, you send commands to your local repeater via RF, which tells the repeater/hotspot to “link” to a reflector. Once the repeater is linked to a reflector, every station using that repeater (if properly configured) hears every other station on the reflector. You can think of a reflector as a “mega-repeater”. D-STAR requires registration of your callsign with any one repeater within the D-STAR network in order to be allowed to perform link/unlink operations, but you can still transmit over/via D-STAR repeaters without registration, and if someone else has linked that repeater to a reflector, your signal will go out over the reflector. I recommend registration via https://regist.dstargateway.org/ , which is a community-run registration portal that often validates registrations within minutes or hours rather than days (sometimes weeks) when registering with some repeaters.
 
 
 
D-STAR radios come with a pre-installed list of all known D-STAR repeaters, worldwide. This means that when you travel, you can go into the radio’s D-STAR menu, and (using the radio’s GPS data) find the nearest D-STAR repeater, and just start using it. You will still want to program in local analog repeaters, but – unless you delete the list (which you can download a new copy from the internet and reload into the radio) – you can almost always find a nearby D-STAR repeater. Whether or not that repeater is “nearby” enough to be reachable, of course, depends on a number of factors. D-STAR also sends callsign and operator information with each transmission, so you don’t need to continuously update a callsign list on your radio (unlike DMR). Many D-STAR radios also support D-PRS, which will send (if configured; this can be disabled) your location and other information to APRS-IS, so APRS users can track your location. Potentially handy for travel, hiking/SOTA, etc.
 
When I travel, I count on D-STAR. A couple of weeks ago, I had to make an immediate, unplanned visit to Western NC. When I arrived at my location, I found that there was no cell coverage, which also meant no mobile hotspot*, so I checked my radio for a “nearby repeater”, and found one that I easily could reach. I used that repeater to connect to a reflector where I could talk to other hams, possibly having them send messages on my behalf if needed. I have also similarly used my D-STAR HT multiple times when traveling for work to connect to repeaters that I had no idea about until I turned on my radio and chose “near repeaters” from the menu.
 
 

*Hotspots: I often use a hotspot – a “mini, personal RF- and internet-connected repeater” – instead of bothering with repeaters. Hotspots allow you to connect to reflectors, just like a full-sized repeater, but have incredibly limited range due to their very, very low output power and tiny antenna. There are multiple options for hotspots, and most will work with all of the major digital voice modes.

 
All of the modes have their positives and negatives. D-STAR is my favorite, due to its flexibility when traveling, and DMR is my least, for its lack in that same aspect. I still use my DMR radio, however, especially around here, where DMR is so prevalent, and D-STAR, not so much.
 
Ok, so this was more information than I had intended to send. Feel free to reach out if I can help answer any other questions.             73 de K7AJG . .