Editor’s note and update: This article originally appeared on n2rac.com in August 2018. I have again become active on digital radio, particularly DMR and C4FM. I am usually listening in at BrandMeister Talkgroup 51518, which is crosslinked to the YSF network and the DX1ARM System Fusion repeater in Metro Manila. I will need to write another article that explores the world of DMR and crosslinked systems for hams.

Planning to go digital? Here are some considerations

I have often been asked about the benefits and disadvantages of digital radio, having been one of the relatively early adopters of at least one digital standard in the Philippines (C4FM). My answer is, usually, “it depends” and that “there is no short answer.”

To start with, I am a bit ambivalent about the new digital modes. Digital radio, by definition, is actually not new, as the earlier generations had actually utilized digital in some form. In fact, even Continuous Wave and Morse Code can be considered digital, if you count the dots, dashes and empty spaces as “digits”. There were RTTY, PSK, PAKTOR, etc. Any form of modulation that utilized digits instead of voice can be considered a digital means of modulation.

Now let’s focus on the newer kinds of digital modes, such as C4FM, DMR, D*Star, etc. The question is often whether it’s worth it to take the plunge and upgrade. Again my answer is “it depends.”

You need to ask yourself a few questions first:

  • What is your main goal with upgrading to digital? Is it for better clarity? Do you want to make contacts across the globe via internet linkages?
  • Do you have access to internet links, such as a node (Wires-X, DMR, etc.) or a hotspot (dv4mini, openspot, nanospot, etc)?
  • Are you interested or willing to setup such internet linkages should there be no other option?
  • Have you considered the cost of these devices? It’s not just the radio itself, but you might need to acquire additional gear like a hotspot, and a reliable internet connection.
  • What about the community? C4FM seems to be popular, but there is a resurgence of DMR among the amateur community in the Philippines
  • Consider differing standards — each standard or brand comes with its own digital modulation standard/scheme, and they all differ in the way you connect across the network. Each standard works only within the same network, unless there are crosslinks at some point.

In my opinion, “clarity” should not be the main consideration when going digital. Sure, you are assured of 100% great quality audio until a certain point in signal fade. But that’s also something you get with other channels or modes of communication, depending on the codec — say on Skype, Zello, TeamSpeak, Echolink, etc.

In addition, there is a marked difference between digital and analog audio not just in terms of quality, but in terms of how our brain perceives the sound. It is, again, subjective. But many audiophiles appreciate the noise that comes with analog audio. There is character, and there is a certain feel to audio that is real and not just a product of ones and zeros. In fact, some sound engineers deliberately add some noise to song recordings (think of Maroon 5’s “She Will be Loved” for example).

Thus, at least for me, the “pure” and “crystal clear” audio sounds a bit unnatural, especially coming from a radio. When I talk on Zello or TeamSpeak, or a Network Radio, I would expect such. But when I am modulating on RF, I tend to think that some noise adds character. Besides, when you get a Q5 audio and S9 signal, it’s practically like you’re talking to a neighbor, but the voice is still markedly different from the robotic sound of C4FM.

That being said, I believe that it’s the network inter-linkages that will be beneficial here. As I have written before, digital modes enable us to QSO with faraway stations via the internet (by some opinion, just another form of “propagation”). And there are the added features, like APRS, GPS geo-location, text messaging, etc.

I have learned a lot in my involvement in Wires-X nets (technical net, international net), as well as my current involvement in Zello and IRN groups discussing “network radio”. By the end of 2017, I sold my FT2DR, FT70DR and dv4mini, however. I might still venture into DMR or perhaps again C4FM, but not in the foreseeable future.

So, when someone asks me about digital, my answer will be: It depends! But here are some considerations I have raised. You might have a few, and you might have read some opinions. Please do share and be part of the discussion.

You might want to check out a previous article I wrote about digital.

Here is an article about imperfections in audio recording (not mine).

Photo by Drew Patrick Miller on Unsplash

1 Comment

  1. Jojo

    I like the content. Amazing how you explain it.

    Reply

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