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: Left-2
ad: abrind-2
ad: L-MFJ
ad: Left-3
  1. W4EAE

    W4EAE Premium Subscriber QRZ Page

    I would be happy if the FCC ruled that AMBE could not be used for amateur radio purposes. Then, maybe, we could get back on track; a bunch of firmware updates that included an open source software codec.
  2. SM0AOM

    SM0AOM Ham Member QRZ Page

    I find this somewhat unlikely in the shorter time-span,
    as there still must be at least one or two radio communications professionals left among the decision-makers within the FCC.

    But, when they have retired and all been replaced with MBA:s and lawyers, anything can happen.

    KX4O, NL7W and W4EAE like this.
  3. W4EAE

    W4EAE Premium Subscriber QRZ Page

    If it takes MBAs and lawyers to get corporate interests out of amateur radio, great.
  4. K7JEM

    K7JEM Ham Member QRZ Page

    Corporate interests are actually one thing that makes ham radio great, and viable.
    KX4O and AI7PM like this.
  5. WQ4G

    WQ4G Ham Member QRZ Page

    I want to make sure I understand what you are saying... When you said, 'Talk to anyone, anywhere, anytime with data,' you mean through the Internet - right? What happens when the Internet goes down? And, can't you already talk to anyone, anywhere, anytime with a Cell Phone, Smart Phone, I-Phone, or Computer? Talking to someone over the Internet, IMO, is not the same as bouncing Radio Waves off the Ionosphere. There are no chance encounters, no fun, and IMO requires almost no skill.

    Yep, FM's days are numbered. Just like CW and AM.

    If digital radio is anything like Digital TV then I will KEEP my analog VHF FM rig. Digital TV does not work so well for me. It's is absolutely GREAT when it WORKS. But, like all the other modern technology I have seen it is a real bummer when it doesn't work. When atmospheric conditions are not so good DTV is absolute (expletive deleted). My OTA DTV reception even goes kaput when a Helicopter flies between my QTH and the TX antenna. It goes out when there is rain between my location and the TX antenna, it goes out when there is Fog, I have even seen it go out when the wind blows too hard. Didn't have that problem when TV was on analog signals. Yes, the signal would degrade some, but it would never go completely out and could still be depended on in times of inclement weather. Unfortunately, I can NOT say the same about OTA DTV. And, that is with my antenna at twice the height it was when TV was analog. I had to double my antenna height to even receive OTA TV.

    Same thing at work when we were on NEXTEL. The Phone and Radio worked GREAT when it was good weather. But, when it rained, when there was fog, or when the wind blew too hard the system did not work. I have even seen our NEXTEL system taken down by too much smoke in the air.

    I will go to digital ham radio when I am forced to. But, until then I will respectfully remain an analog operator.

    Perhaps someone could comment on why digital signals degrade so much in bad weather?

    Dan KI4AX
    WN1MB and K2WH like this.
  6. AI3V

    AI3V Ham Member QRZ Page

    And there is the crux of the matter.

    There are a infinate number of coding schemes, and they exist as proprietary schemes because of lawyers.

    Not because of technical reasons.

    There is absolutely no tecnical reason that a modern transceiver should not be user programmed to use any type coder, any combination of modes (voice, gps data, video. Whatever), and any transmission style, am,fm,fsk,tdma,qam etc.

    Exactly why cant I run a 1/2 rate bitstream, of a picture of me, using a 64qam tramsmission mode, on a ham radio?

    Instead the argument is which manufacturers box should the club buy.

    WQ4G likes this.
  7. SM0AOM

    SM0AOM Ham Member QRZ Page

    A very justified question.

    I do not see any current rule, despite that the FCC has used some 23000 words in their amateur radio regulations, that generally prohibits your proposed modulation and coding scheme, but a proposed system would be dependent of what would be physically realisable in the frequency band(s) intended with regard to available bandwidth, propagation and RF power.

    One problem, as I see it, is that the FCC rules have grown byzantinely complex and sometimes contradictory. They also contain quite archaic limitations, where the maze of sub-bands and symbol rate ruling stand out.

    It would be of general interest to get some background to why the FCC rules have grown so extensive and complex. After all, it is the same international hobby that other countries have managed to regulate using regulations with a word count in the range 1000 or 1500 words.

    The amateur radio bands are becoming more and more "dead air" in Europe for every year, so no-one raised an eyebrow when a few technically inclined amateurs some years ago tried wide-band digital voice using more than 200 kHz bandwidth in the 80 m band.

    In several countries there are neither any limitations of allowed bandwidth except the band edges, or sub-bands nor any prohibited transmissions, but most people seem to be generally playing nicely with each other despite this.

    The "LIDS" do not obey regulations anyway.

    Last edited: Jul 21, 2019
    KX4O, NL7W and AI3V like this.
  8. KF5LJW

    KF5LJW Ham Member QRZ Page

    Not entirely right, any media be it optical, electrical, wireless, or recorded.

    Moot Points because you made the wrong assumptions. What if your radio quit working?

    Do as you please, only person being hurt is yourself missing out on something you might like. Most of the rigs that run digital also do conventional FM. You do not know what you might be missing.

    All this suggest one of two possibilities. One you live in Fringe Area. Secondly could mean your antenna circuit needs upgraded using antenna specific to OTA channel frequency and a good LNA is required. If you are in the Fringe with a good setup, you are SOL unless you go CATV or SATV. I grew up on analog TV in the 60's with a antenna up until the 90's before we got CATV. I remember well it was crappy on its best days, and CATV Analog was still crappy Even yours was crappy compared to Digital. Sounds. That helicopter thing still happened on analog as I remember quite well because we lived 2 miles from Tulsa Airport. Every time a plane took off or landed would tear up the picture from Multi-Path.

    Now if you want to say analog Conventional FM and AM has better range is a true statement. But over exaggerated IMO. When you get down in signal level to a point equal to conventional FM 12 db SINAD is where digital will begin taking bit errors. As you go down from there the BER rate becomes high enough that the signal is unusable. On conventional FM 12 db SINAD is where it starts getting scratchy, and below that gets real scratchy real fast.

    Sorry I got to LOL on that one. Not sure how to say this because it is not PC to use the word "queer" anymore. Lets try this. Nextel was the oddball of the wireless carriers. They went out of biz in 2003 when Sprint shut off the last cell site. What made Nextel an oddball is they used IDEN which is basically a digital Trunked Radio system that was already antiquated. Wireless world at that time was either CDMA or GSM digital. None of Nextel equipment was compatible with what the rest of the world used. Even the UI device, (your 90's Flip Phone) was unique, so not many phone manufactures made UI's for users. Couple that niche oddball market with a limited number of sites, you had a POS wireless company. Only one worse phone company today than Nextel, that would be Sprint who bought Nextel and darn near bankrupted Squirt.
  9. WA9SVD

    WA9SVD Ham Member QRZ Page

    I thought the U.S.'s FCC's Board (bored?) or whatever was now comprised solely of lawyers, MBA's and other "legal Beagles," no amateur license to be seen. Far be it the FCC should have any understanding of telecommunications!:rolleyes: THAT might be construed as a "conflict of interest.":mad::rolleyes:
  10. WN1MB

    WN1MB XML Subscriber QRZ Page

    Easy answer: because digital sucks. ;)

Share This Page

ad: AlphaRF-1