Why I wont get a D-Star Radio
Posted by Mike G7FEK on Sat, 25 Apr 2015 15:41:40 +0100

VHF amateur radio is not so busy these days. Is D-star good or bad for Amateur Radio.

Back in the 1980s when I was first licensed, the 2m band was fairly busy much of the time. There was a call for a shift from 25 KHz to 12.5 KHz channel spacing and that eventually became the standard, doubling the number of FM channels.

In 2015 there is hardly a sound on 2m FM, at least where I am located, and more than enough channel space. FM Repeaters are just beacons most of the time. So what is the benefit of moving them to a proprietary digital mode?

Digital is an expensive investment for the average Amateur, considering we already own FM transceivers and they can also be bought cheaply. Why not just use the equipment we,ve already got for now, and if we do want a digital system, why not pioneer our own. A dual mode, compatible open system, rather than use a system intended to tie us to Icom radios. That,s the way we used to do things. We didn,t just buy stuff.

Amateur radio is an unimportant, obsolete technology today. Moving to digital will not make it any less so. It is now just hobby radio, so lets not raise the price barrier too high when we dont need to.

Anyway, that,s my thoughts and ramblings, I,m sure its been said already time and time again, but i was asked today why I didnt have D-Star. I guess the simple answer is that I don,t think its worth the investment just to talk to people I can already talk to on FM. Id much rather see people do try VHF simplex on both FM and SSB, but I think those days are long gone.




Comment by 'Mick M5AED (G-QRP Club 9486)' on 11 Apr 2016 - comment
“Mike, I fully agree with your D Star comment. My Yaesu FT991 has Fusion. Used it once with a local station, unpleasant compressed audio. I remember when FM simplex channels were busy but no need for more modes / channels today. Enjoyed the QRP contact on 40m today, forgot to ask which part of the I.O.W you were on ?”

Comment by 'Andrew' on 27 Apr 2015 - comment
“Sorry I did not intend to post the same reply 3 times, operator error... 😁”

Comment by 'Andrew' on 27 Apr 2015 - comment
“The audio quality is amazing, Q5 at 0 signal level is easily obtainable with digital. I won't says its true HiFi.. there is a slight roboticness to its sound, but you soon get used to that. I have heard better with some of the commercial PMR digital transmission but its 0 noise with your spoken audio is great. The one small drawback here though is if your in a fringe area to the repeater, instead of your audio fading into the noise floor you do tend to " drop off a cliff" with digital but the rf does seem to carry further with dig than it does with analogue fm, in a watts for miles type comparison. With digital You also transmit data at the same time as voice, people usually send their name and qth info, but you can also send your GPS location. Which you can read from the radios receiver. So you can have a bearing and distance away from the person you are talking to. The data transmission also allows you to send pictures or pc files whilst you are talking. The dstar protocol allows you to choose where to link or not link your repeater, by sending a simple data string. You can connect to another dstar repeater or one of the many chat rooms (reflectors ) which as said in an earlier reply could have an average of 60 or so other repeaters also linked in. So there is usually always someone to talk to. Andrew.”

Comment by 'Andrew' on 27 Apr 2015 - comment
“The audio quality is amazing, Q5 at 0 signal level is easily obtainable with digital. I won't says its true HiFi.. there is a slight roboticness to its sound, but you soon get used to that. I have heard better with some of the commercial PMR digital transmission but its 0 noise with your spoken audio is great. The one small drawback here though is if your in a fringe area to the repeater, instead of your audio fading into the noise floor you do tend to " drop off a cliff" with digital but the rf does seem to carry further with dig than it does with analogue fm, in a watts for miles type comparison. With digital You also transmit data at the same time as voice, people usually send their name and qth info, but you can also send your GPS location. Which you can read from the radios receiver. So you can have a bearing and distance away from the person you are talking to. The data transmission also allows you to send pictures or pc files whilst you are talking. The dstar protocol allows you to choose where to link or not link your repeater, by send a simple data string. You can connect to another dstar repeater or one of the many chat rooms (reflectors ) which as said in an earlier reply could have an average of 60 or so other repeaters linked. So there is usually always someone to talk to. Andrew.”

Comment by 'Andrew' on 27 Apr 2015 - comment
“The audio quality is amazing, Q5 at 0 signal level is easily obtainable with digital. I won't says its true HiFi.. there is a slight roboticness to its sound, but you soon get used to that. I have heard better with some of the commercial PMR digital transmission but its 0 noise with you spoken audio is great. You also transmit data at the same time as voice, people usually send their name and qth info, but you can also send your GPS location. Which you can read from the radios receiver. So you can have a bearing and distance away from the person you are talking to. The data transmission also allows you to send pictures or pc files whilst you are talking. The dstar protocol allows you to choose where to link or not link your repeater, by send a simple data string. You can connect to another dstar repeater or one of the many chat rooms (reflectors ) which as said in an earlier reply could have an average of 60 or so other repeaters linked. So there is usually always someone to talk to. Andrew.”

Comment by 'Mike G7FEK' on 26 Apr 2015 - comment
“Thanks for the info Andrew. Ill look into it in more depth. But I still cannot see why we need to split the already sparse number of VHF users into incompatible sub groups. I,d like to know, What real benefit does D-Star offer over FM that makes it worth the extra investment?”

Comment by 'andrew' on 26 Apr 2015 - comment
“Dstar is not a closed system to only ICOM radios. Dstar was the creation of the JARL. Its is an open platform, only the vocoder used is the intellectual property of dvsi the company that builds the chip. There is a lot of homebrew and experiments going on in dstar. There are repeaters that only use a pc's soundcard, there are manufacturers who provide equipment to work dstar interfacing to your analogue radio. There are many many other hardware developers and experimenters where dstar is concerned Google dvrptr v1, or moencomm or dvmega or g4klx dstarrepeater or nw digital. So when your local FM repeater is quiet come join us on a mega reflector, when maybe 60 or so dstar repeaters, hotspots and nodes could be connected at any one time.. Andrew.”