I love it (FM)! I would use it more if I could (well, radio in general). During the last solar peak, on a few occasions, I worked a few Toronto stations using FM. 1700 miles from my location here in Western Canada.
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US WWDXers: Will you be getting a FM rig?
- Thread starter cralt
- Start date
I will admit that SSB is better simply because of narrower bandwidth and increased signal/noise ratio, you are far off in reality. I have used HF to work FM on 10m many times both simplex and via various 10m FM repeaters most notably the 29.560/660 repeater in the US Virgin Islands. I have also used 6 watts FM carrier to work stations in the United Kingdom many times even from the mobile. Working 10m FM is actually fun.......unless you are a stick in the mud and only worried about how much you are stomping on the other guys.
Because weaker FM signals easily get lost into the LOUD FM background noise that you get with the Open Squelch. So on FM you pretty much have to operate Closed Squelch all the time. Somebody giving you an S 1,2,3 signal on AM .... you can easily hear them all day long. Same weaker signal on FM won't even open your squelch and if it does it is mixed into the loud background noise and you can't hear them or it is a really hard unbearably noisy copy. Nobody who talks in a spread-out local group will tolerate this situation with the guys on the fringe being cut out of the talking.
Greetings from Montana. FM would be great if there were an agreed upon convention among operators that its use would be usually confined to a few designated channels, as is generally done with SSB. FM is easy on the ears when it is full quieting. In urban areas, the usual sociopathic Channel Czars will emit gross amounts of power and because of FM's capture effect, will literally act as gatekeepers of "their" channels. SSB is much easier on power supplies, batteries, components, amplifiers and antennas having power limits. Also, it's possible to hear and understand more than one station on SSB when one is not substantially stronger, making it easier to break in, and to hear in the clear, as alluded to by Captain Kilowatt. FM is ideal for those nice rag chews and evening chats on long drives or when in a spread out caravan. If you were to draw two horizontal lines -- one for SSB and the other for FM -- originating from a point on the left representing a transmitter, extending to the right as effective ground wave communication distance, with the line dropping in height as the signal produces less response in receivers to the right, the SSB line would have a gradual slope and not precipitously drop out to the bottom noise level until it was very close to that noise level. The FM line, by contrast, would remain nearly horizontal until it reached its fringe, and would then drop like a rock into the abyss; its line would not extend anywhere near as far as the SSB signal's line would. So, it really depends upon the application, as well as the cooperative attitude of operators. With luck, it will sort itself out as SSB operation on 11M generally has. If FM-ers come to dominate channels 1-23, then there will be an exodus by many AM-ers to the LSB channels for relief, with mixed effects. The FCC has basically indicated that it will finalize an order granting the petition, which it usually does when the Electronic Industries Association gets behind something. The last time I recall the EIA being denied a petition was in the 70s when "Class E CB" was proposed, using the 220 MHz amateur band which would have ceased to be a ham band. EIA isn't the petitioner here, but supports the change. It will work out and yes, I'd expect fire sales on good AM/SSB radios as soon as the regulatory change is effective.
I use CB down here to keep in touch between the house and the boat. The FM option will be terrific in that setting because it isn't as vulnerable to ignition and flourescent lamp caused RF interference. There's almost no CB traffic down here, so I'll have the full band to myself. But that doesn't mean I'm tossing my collection of 40 channel CBs or my SSB units.
And here it is. FM now legal in USA (edit: next month) 
https://www.federalregister.gov/doc...the-commissions-personal-radio-services-rules
https://www.federalregister.gov/doc...the-commissions-personal-radio-services-rules
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The Commission grants the Cobra Petition to the extent described in the Memorandum Opinion and Order on Reconsideration. Specifically, the Commission amends Section 95.971(a) of the Commission's rules to permit CB Radio Service transmitters to transmit FM voice emissions along with AM. The Commission notes that AM and FM operations are permitted in other Part 95 services under similar technical parameters, so the Commission generally applies the technical rules to FM signals as currently apply to AM signals for the CB Radio Service. In the case of peak frequency deviation, however, the Commission adopts a limit of ±2 kHz due to the 10 kHz channel spacing and 8 kHz occupied bandwidth maximum in the CB Radio Service. Although this specific limit differs from those established in other Part 95 services ( e.g., ±5 kHz for 20 kHz channel bandwidth and ±2.5 kHz for 12.5 kHz channel bandwidth in both General Mobile Radio Service (GMRS) and Multi-Use Radio Service (MURS)), it is consistent across Part 95 services considering the respective occupied bandwidths. The Commission also finds it appropriate to use the common FM emission designator used for Part 95 GMRS and MURS for FM CB Radio Service. These technical rules are implemented through the amendment of Sections 95.967, 95.971, 95.973, 95.975, and 95.979 of the Commission's rules to reflect the addition of FM as an optional additional mode of transmission. The Commission notes that parties planning to incorporate the FM mode into CB radios will have to obtain a valid grant of certification under the Commission's equipment authorization rules.
the cobra petition was originally filed on June 23, 2017.
the cobra petition was originally filed on June 23, 2017.
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Looks to me like it is not in effect until October 28, 2021 so still not legal for another month.
Sure I'll be using it . I have several radios that have 11m FM capabilities. So , why not?
I will be using FM at certain times on the Anytone 5555 V6 I picked up last month. It will be only very local as far as reach. I tried it out, and it works well, but it is not something I would use daily due to the noise. I have always run with no squelch. I like to hear anything far off. FM seems to be no good like that at all.
I can see a CB modification opening up to add FM to all these old AM only CBs, if somebody doesn't have it already. I already own too many old but good CBs.
FM on these CB or Export radios are AGC squelch level activated, where a dedicated FM receiver like what is in a Ham radio 2M rig or HT or business band radio (Police/Fire etc...) is Noise level (high frequency SHHH noise) activated. FM with Noise level activation "opens" upon receiving a carrier that "quiets" the noise, what is called "Full Quieting".
So, any add-on FM boards should have a Noise activated Squelch circuit. Or, an add-on board can be added that activates on Noise level when in FM mode on these radios that already have FM in them.
I used to build FM add-on boards on perf-board about 35+ years ago, but not with Noise Activated Squelch.
So, any add-on FM boards should have a Noise activated Squelch circuit. Or, an add-on board can be added that activates on Noise level when in FM mode on these radios that already have FM in them.
I used to build FM add-on boards on perf-board about 35+ years ago, but not with Noise Activated Squelch.
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