C4FM Thing of the past or of the future?

Discussion in 'VHF/UHF - 50Mhz and Beyond' started by N7BKV, Jun 22, 2019.

ad: L-HROutlet
ad: l-rl
ad: Subscribe
ad: L-MFJ
ad: Left-2
ad: Left-3
ad: abrind-2
  1. KB1UMC

    KB1UMC Ham Member QRZ Page

    I've been out of the hobby for a few years and just getting back in. That said if these communications C4FM, DMR, etc are nothing more or less than VOIP solution protocols are you comfortable with the fact that if you don't have an Internet connection all of this goes away? At least that's my understanding.

    If that's true, then much of the purpose of HAM Radio was to provide communications in disaster scenarios....thus being independent as FM is, these protocols are fully dependent upon an Internet connection.

    Have I got that correct? If not, school is now open!
  2. ND5Y

    ND5Y Ham Member QRZ Page

    Internet (or other private network) connections are only required for linking.
    You can operate digital modes simplex or through a stand alone repeater just like regular analog FM.
    AI7PM likes this.
  3. KF5LJW

    KF5LJW Ham Member QRZ Page

    Internet has nothing to do with it. You can link repeaters with analog copper wire if you want.

    Ham operators days of emergency and disaster communication is long gone. It is just a hobby today. On the commercial LMR and Public
    Safety side of the coin, FM is on life support, in hospice care, and the end is near. Just a few low end biz and poor districts are the only ones left using FM. LMR and Public Safety are going P2 Phase 2. Part of the reason is bandwidth. Today with digital you can put 4 voice or 2 data channels onto a conventional FM repeater channel. Digital is far more efficient and bandwidth is a commodity up for sale to highest bidder. Technology antiquated ham radio operations.
    N7BKV likes this.
  4. N7BKV

    N7BKV Ham Member QRZ Page

    Well said. Technilogically modern telecomm is WAYYYYYY beyond the hobby level. Maybe some hams who work in the telecom industry or teach the stuff in engineering schools can do a bit of it as a hobby. But I suspect that most of us were left on the dock a long time ago.

    Enjoy our hobby. It's like playing chess in an age of video games. And like chess, it will never go away.

    Your move.


    Brian N
    N1OOQ, 2E0JTP and K8HIT like this.
  5. KB1UMC

    KB1UMC Ham Member QRZ Page

    So, I think what you're saying is that FM Analog is being replaced by a Digital signal just like the old analog phone lines have mostly been replaced with Internet VOIP (which is really digital per se).

    I have a few more questions then. If I'm on 2M and 70cm using repeaters nearly 100% of the time doesn't the repeater itself need to support the digital protocol of the radio I'm using to take advantage of the digital signal? So if the repeater doesn't use D-Star and that's what my radio uses what happens? Does it fall back to FM analog or is one out of luck?
  6. KF5LJW

    KF5LJW Ham Member QRZ Page

    Not being replaced yet, a winner has not been declared. On the commercial side, 2 winners were declared. Thus conventional FM on the Commercial and Public Safety side is on its way out. They settled on 2 Standard Protocols.

    That battle has not played out yet with Amateur bands. It became necessary on Commercial and Public Safety because the FCC changed channel bandwidth from 25 Khz to 12.5 Khz or half the bandwidth doubling the number of Frequencies available for sale. No problem with Digital, not only is it no problem to shrink the bandwidth for a single voice channel, you can put 2 voice channels or 1 data channel packed in 12.5 Khz of bandwidth. Much more efficient use of a very valuable commodity.

    You have three competing modes on 2m and 70cm, really any band I think. Who knows if it will be C4FM, D-Star, DMR, or nnone of the above. May not happen at all because some of the modes require the operator to have some logic skills with routing. A 3rd grader can operate conventional FM. The other crowd does not like the voice quality.

    Pay your money, take your chances.
    AD7VB likes this.
  7. ND5Y

    ND5Y Ham Member QRZ Page

    Your radio and the repeater both have to be the same digital mode.
    Some repeaters support multiple digital modes and analog FM.
    Some repeaters are digital only and not capable of analog FM.
  8. KC4FA

    KC4FA Premium Subscriber QRZ Page

    I have DMR, Dstar and C4FM HT radio's with a OS2 Hot spot in my Home. Dstar seems to be the most active with Hot Spot. Every area has different repeater activity. Digital radio has its place in ham radio, but Don't throw away your VHF and UHF FM Analog Hand Held radio's. If the internet goes down, no Internet Digital radio. Make sure your analog FM radios have charged batteries
    K8HIT likes this.
  9. W4EAE

    W4EAE Premium Subscriber QRZ Page

    Yes. Always keep FM radios handy, if for not other reason than that nearly every single amateur also has one.

    No. Internet is necessary for linking repeaters, but no more limited than FM in terms of usability without the internet. Digital repeaters still function as repeater so long as they have power. In fact, digital voice modes over simplex can often outperform FM when the path is obstructed by buildings or foliage at 2m or 70cm . FM still wins in terms of sheer distance over an unobstructed path.
  10. 2E0JTP

    2E0JTP Ham Member QRZ Page

    As much as digital technology has already and will continue to replace analogue, this is a good enough reason not to throw away analogue radios, and I say this as someone who has actively and enthusiastically embraced digital.

    The ability for computer networked radios to communicate across different digital modes is great, but having an underlying simple mode (FM) that allows everyone to talk to everyone else regardless of brand is something we should never be too eager to give up.
    K8RGB likes this.

Share This Page