Fm mode on CB band

Discussion in 'Survival Communications' started by DKR, Aug 29, 2021.

  1. DKR

    DKR Raconteur of the first stripe
    Federal Communications Commission FCC-CIRC2108-06
    July 25, 2021

    Money quote
    "Accordingly, we grant the Cobra Petition to the extent described herein.24 Specifically,
    we amend Section 95.971(a) of the Commission’s rules to permit CB Radio Service transmitters to transmit FM voice emissions along with AM.

    We note that AM and FM operations are permitted in other Part 95 services under similar technical parameters,26 so we generally apply the technical rules to FM signals as currently apply to AM signals for the CB Radio Service. This approach is the same as that taken in other Part 95 services.27 In the case of peak frequency deviation, however, we adopt a limit of ±2 kHz due to the 10 kHz channel spacing and 8 kHz occupied bandwidth maximum in the CB Radio Service.


    We note that the ±2 kHz limit is the current European standard for CB radios that use AM and FM transmissions, thereby facilitating equipment compatibility.

    Effective 30 days after publication in the Federal Register.

    I just might buy one of these to see how it plays here in town....
  2. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    Interesting… Been watching for this for a few decades.. and finally reason has prevailed, at FCC HQ… We had discussions, on this issue, when I was a Resident Field Agent..
  3. BenP

    BenP Monkey++

    @BTPost , @DKR Is there a DMR radio that will function on that band?
  4. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    Seems to me that the PRC-152c SDR Radios can be programmed to function in the CB Band as narrow band FM, as well as they may be programmed in most of the DMR Bands and modulations…
    Well close, but no cigar… the PRC-152c lower frequency limit is 30 Mhz, so No it will not go to the 27 Mhz CB Band.. however the older PRC-150 will do it but not the DMR Modulations and not above 50 Mhz..
    BenP likes this.
  5. BenP

    BenP Monkey++

    Where would one find such a creature?
  6. Gafarmboy

    Gafarmboy Monkey+++

    The sole purpose of this anomaly is to force you to buy a new unit. Older units,, will pick up fm signals and know not what they are.. Sponsored by cobra and President brand radios. If it were real change, they would have monkeyed with the channels.
    Homer Simpson likes this.
  7. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    I used Bing to find the specs on these two .MIL Radios…. Amazon & eBay, or some of the .MIL Surplus Houses… I bet you could make a good deal on any of them in the Kubal Street Market, for Gold, these days…
    I know that I could load these as PreSets into ANY of my Kenwood HF Radios.. TS-590s, TS-480Sat, TS-480HX, B-2000s, or TS-2000x… as they already have the CB Channels loaded, in AM, & SSB, and all it would take is to hit the Mode Button…
    BenP likes this.
  8. DKR

    DKR Raconteur of the first stripe

    CB Long Range and Mode Test. Part 2. AM vs FM vs SSB. FM on CB 27mhz. RCI-2950 vs Anytone AT-6666 - YouTube

    now that FM rigs are on the market - a demo
    The video clearly shows SSB is a superior mode in terms of distance. FM, on the other hand, will allow DTMF or CTCSS (tones) to provide SELCALL or to use with gadgets such as remote control of gates and such.

    If you buy a unit with all 3 modes, good. If you must choose, then a unit with Am/SSB only will provide the best service or a wider area. Manyy older AM/SSB unit show up on the used market.
  1. Illini Warrior
  2. William Warren
  3. JA40
  4. Tully Mars
  5. bumpshadow
  6. hitchcock4
  7. DKR
  8. Bandit99
  9. BTPost
  10. DKR
  11. BenP
  12. Hanzo
  13. Asia-Off-Grid
  14. Asia-Off-Grid
  15. ED GEiN
  16. ED GEiN
  17. BenP
  18. Idahoser
  19. hitchcock4
  20. Southbound
survivalmonkey SSL seal warrant canary