KD7UGY said:
F3 emissions are allowed on all amateur bands below 29 MHZ with the exception of 30 and 60 meters...but...there is a limit to the maximum permissible deviation. The signal can be no wider than its A3 (full carrier) counterpart.
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Fm vs Am
- Thread starter weatherman49
- Start date
F3 emissions are allowed on all amateur bands below 29 MHZ with the exception of 30 and 60 meters...but...there is a limit to the maximum permissible deviation. The signal can be no wider than its A3 (full carrier) counterpart.
OP WROTE!
Simple, stay on your privilaged band.
Well thanks again guys I see the ham police have arrived! If ya know what I mean but anyway like I said before just throwing Ideas around hoping to find a solution but some folks would complain if ya hung them with a new rope! Well i'm outa here before Mr. high and mighty decides to call me names again and show his true intelegence!!
Simple, stay on your privilaged band.
Well thanks again guys I see the ham police have arrived! If ya know what I mean but anyway like I said before just throwing Ideas around hoping to find a solution but some folks would complain if ya hung them with a new rope! Well i'm outa here before Mr. high and mighty decides to call me names again and show his true intelegence!!
hi all
1. all the 10m radios have fm modes but you never hear any one mention using them Why not?
this is because in part FM is banned for use below 29 mhz
ofcourse that will not stop all..just as many use power and frequencys they are not licenced for..
However due to the higher bandwidth FM
Most who have used it or tried it
quickly realise FM is good only for local contacts
is next to useless for skip
2. from what I understand you have to have a higher power level to broadcast an fm signal the same distance as a lower power am signal ?
basiclly yes...much higher....even then it is usally a lost cause
look at AM verses SSB and you have a slightly better understanding....except that it is far harder to talk FM skip
3. will a am signal be heard on fm if on the same freq?
yes and no..
if one on am is close enough
the one on am will hear the one on fm and almost be able to understand what the person on fm is saying (but not quite)
sort of sounds as though person who is on fm is not tuned in to frequency properly and yet ajusting frequency and or slider will not help matters..lol
now with those out of the way my thought was this if you gave the 40ch 11m radios fm mode that would almost be like giving them an extra 40 channels and that would be cool as ice!
no not like extra channels....closer interpitation is comparing AM to SSB those use same frequency's just different modes
in that regard FM is just a different mode as is Am SSB CW etc
Or is there an allocation already in exsistance for 11m fm I looked but could not find anything?
yes and no
meaning europe and the land down under (not sure about the rest of the world)
they use FM for CM
BUT
the frequencys they use FM on is in the VHF or UHF (i would have to look it up to see which....you can see FM cb's on Ebay)
nowhere is 11 meter frequency have a allocation for FM mode use
Now with all that said
FM sounds better (fuller and truest to hearing someone speak in person)
but due to the much greater bandwidth
it is unpractical to allocate it to be used in 11 meter band
if it ever was so allocated
the 40 currant channels now in 11 meter use would be cut in half
F.C.C. perhaps would like it in that it would stop the way skip is used on SSB (and to a slightly lesser extent AM)
Later
1. all the 10m radios have fm modes but you never hear any one mention using them Why not?
this is because in part FM is banned for use below 29 mhz
ofcourse that will not stop all..just as many use power and frequencys they are not licenced for..
However due to the higher bandwidth FM
Most who have used it or tried it
quickly realise FM is good only for local contacts
is next to useless for skip
2. from what I understand you have to have a higher power level to broadcast an fm signal the same distance as a lower power am signal ?
basiclly yes...much higher....even then it is usally a lost cause
look at AM verses SSB and you have a slightly better understanding....except that it is far harder to talk FM skip
3. will a am signal be heard on fm if on the same freq?
yes and no..
if one on am is close enough
the one on am will hear the one on fm and almost be able to understand what the person on fm is saying (but not quite)
sort of sounds as though person who is on fm is not tuned in to frequency properly and yet ajusting frequency and or slider will not help matters..lol
now with those out of the way my thought was this if you gave the 40ch 11m radios fm mode that would almost be like giving them an extra 40 channels and that would be cool as ice!
no not like extra channels....closer interpitation is comparing AM to SSB those use same frequency's just different modes
in that regard FM is just a different mode as is Am SSB CW etc
Or is there an allocation already in exsistance for 11m fm I looked but could not find anything?
yes and no
meaning europe and the land down under (not sure about the rest of the world)
they use FM for CM
BUT
the frequencys they use FM on is in the VHF or UHF (i would have to look it up to see which....you can see FM cb's on Ebay)
nowhere is 11 meter frequency have a allocation for FM mode use
Now with all that said
FM sounds better (fuller and truest to hearing someone speak in person)
but due to the much greater bandwidth
it is unpractical to allocate it to be used in 11 meter band
if it ever was so allocated
the 40 currant channels now in 11 meter use would be cut in half
F.C.C. perhaps would like it in that it would stop the way skip is used on SSB (and to a slightly lesser extent AM)
Later
weatherman49 said:
*********************************************
However its perceived, it IS correct. I mean, after all CB radio has 40 channels and 4 watts (12 SSB). The "rub" comes in when people start showing up without license on the Amateur bands, and I don't think it is totally unexpected that the hams would get a bit huffy about that! No different than if *I* (or anyone else) came in your yard and started pulling up your prized roses!
FM is NOT permitted on CB because of the bandwidth as was pointed out. True, Amateur Radio is allowed FM (and many other modes), but that is because the testing is *supposed* to demonstrate one's knowledge of how his operation may adversely affect others. CB IS restricted simply because, chances are, most of the users simply are not knowledgable of what they are doing and will cause harmful interference to other users. On the one hand, the hams probably resent the fact that people ignore the strict rules of Part 95 and transgress anyway!
And they show up on frequencies they aren't supposed to. The hams get huffy and may even mock the intruders and jeer when they get letters from FCC. But now c'mon, while it may not be in good taste, when its all said and done, can you really BLAME them when, for example, they find Charlie Trucker on 28.085? Or use spectum-wasting FM on CB, or use splattering amplifiers they can hear across the 2nd harmonic of the fundamental? :? And when they say ANYTHING in objection, they are now "elitists" or "stuffed shirts", or a whole host of things, or DARE say anything like "stay in your own back yard"? And that IS the crux of the matter. STAY on the 40 channels. Don't interfere with other users. Stay within the law. When you do that, then you earn respect. Hams have their own "outlaws", but they tend to get caught, too! And, there is, of course, the option of earning the Amateur license and doing legally ALL the things that CB will not legally permit! 73
CWM
Now, guys, try to stay calm. Weatherman didn't seem to me like he was trying to justify doing things like transmitting in the 10M spectrum or using "splatter boxes". Especially the part where he said "I'm just looking into different ways to keep the peace between hams and the CB folk". It sounded like he was looking for an explination as to whether FM were a viable mode for the alocated 11M, and if so why it isn't allowed. It was an innocent and reasonable set of questions.
CWM, comparing a breach of privelages to pulling up someones prize roses is quite a stretch. Walking through their garden or mabey, just mabey peeing on their roses would be a better analogy. That is the difference between trespassing and destruction of property. You could go further and say that an unauthorized transmission is like murdering the person who is on the recieving end, but people would definately catch on that you are blowing things out of proportion.
Just a thought here, but if CB is restricted because they don't "demonstrate {the} knowledge of how his operation may adversely affect others" and "most of the users simply are not knowledgeable of what they are doing and will cause harmful interference to other users" how do you expect these simple minded creatures to have a superior knowledge of the laws they are breaking. Either they are dumb and that explains why they don't know the law or how to operate their equipment, or they are super genuises who unlawfully and skillfully use the some of the same equipment as you to jump on your frequencies to bother you. You can't have it both ways- idiots at operating equipment and taking tests, but fully knowledgable of the laws, reasons for the laws, and all concequences.
Hopefully it is obvious that some of what I say is tongue in cheek but some is right on the money. Lets try to be understanding and listen to others. Weatherman was hoping to create peace through better use of CBs own channels. I applaud him for trying to come up with a solution rather than an attack.
CWM, comparing a breach of privelages to pulling up someones prize roses is quite a stretch. Walking through their garden or mabey, just mabey peeing on their roses would be a better analogy. That is the difference between trespassing and destruction of property. You could go further and say that an unauthorized transmission is like murdering the person who is on the recieving end, but people would definately catch on that you are blowing things out of proportion.
Just a thought here, but if CB is restricted because they don't "demonstrate {the} knowledge of how his operation may adversely affect others" and "most of the users simply are not knowledgeable of what they are doing and will cause harmful interference to other users" how do you expect these simple minded creatures to have a superior knowledge of the laws they are breaking. Either they are dumb and that explains why they don't know the law or how to operate their equipment, or they are super genuises who unlawfully and skillfully use the some of the same equipment as you to jump on your frequencies to bother you. You can't have it both ways- idiots at operating equipment and taking tests, but fully knowledgable of the laws, reasons for the laws, and all concequences.
Hopefully it is obvious that some of what I say is tongue in cheek but some is right on the money. Lets try to be understanding and listen to others. Weatherman was hoping to create peace through better use of CBs own channels. I applaud him for trying to come up with a solution rather than an attack.
KingCobra_CDX882 said:
Not true.
As I've posted before, FM (frequency modulation) and PM (phase, or 'angle' modulation) are both permitted on all amateur bands below 10M - with the exclusion of 30M (CW/data only) and 60M (USB only).
Total deviation may not exceed the bandwidth of a DSB full carrier (AM) signal...which is ~6KHz wide.
In the U.S., FM isn't allowed within the 11M CB service but in other countries - such as the UK - it is permitted.
Thanx Hillbilly I am glad someone caught the piont! All I was getting at was that if 11m used fm that it would ease some of the congestion created by skip and if both modes were implemented maybe there would be fewer people operating out of the frequencies allocated for 11m or freebanding as it's called in certian circles! Now as far as calling Hams stuffed shirts that comment was directed at one and only one person he knows who he is! as for the rest of the hams on the forum so far they have been very helpful and I enjoy listening and learning from them!
weatherman49 said:
True for local communications, and it's due to something called 'capture effect'. Basically stated - The strongest signal in your FM demodulator's passband wins. No annoying heterodynes, but with a large number of stations on any one frequency you'll still experience QRM, flutter and other annoyances unique to the mode.
If anything, allowing both modes to coexist in the same immediate region of the spectrum would make matters worse as they're incompatible with each other. A group of people who suddenly find their favorite AM hangout to be overrun with FMers will either interfere with the newcomers or set out for greener pastures - and probably not in the 'regular 40', either.
N8YX said:
So basically back to square 1!
The reason I am looking into these things is because I personally don't like running out of band and I hope to find a solution! My radio is modded for the simple fact that I cannot talk 15 miles much less the 150 miles Max on the allocated 40 with the type accepted 4W radios! The skip just overruns me and even if not you have 900 Idiots out there going AUDIOOO!
When I test and tune my radios I use a Dummy load thats what It's there for!
My need for the extras came about when I tried to talk to my wife and just couldn't
You say get the ticket sure but I'm only interested in bieng able to tell my wife to grab something on the way home or to tell a friend to meet me somewhere I don't really want to have to go thru all the protocall! I will probably end up with the liscense but for now the fact remains that there has to be a way to stay on my 11m without the annoyance of people who do run dirty radios with clipped audio and splatter boxes!
Someone will say to use the new family radio service! Problem there is range I live about 30 miles out of town the only family radios I've seen have a max range of about 10 miles!
Anyway I'll keep searching and thinking! for those of you that have repleid to this thread in an understanding open minded fashion thanx again!
weatherman49 said:
If you have an AM-only rig, get hold of a pair of SSB units. Many of us are in the same boat as you and need a reliable, medium range alternative to amateur radio. SSB CB (used on channels 36-40) fills that requirement nicely.
They'll do that when the band is completely dead as well. I liken the effect to the old hound dog that howls and barks just to hear itself...
Try the SSB and/or GMRS angles. They might provide you with exactly what you need in terms of dependable communications.
I would like to see that as well - eliminate the interference and there would likely be enough room for everybody...
N8YX
ssb is all good but then ya have to try tuning the reciever and all that jazz! gmrs and the rest of the family services don't have the range I want around 10 miles max from the radios I have looked at around here! and even on sideband you still get the same stuff bleedover and the like still the same prob the reason I was thinking fm is because to actualy interfear you would have to be pretty close to the reciever that was in the am mode unless you ran an ungodly amount of power and that would defeat my whole purpose of clean interfearance free medium range comunications! Within the alloted 40ch 11m!
ssb is all good but then ya have to try tuning the reciever and all that jazz! gmrs and the rest of the family services don't have the range I want around 10 miles max from the radios I have looked at around here! and even on sideband you still get the same stuff bleedover and the like still the same prob the reason I was thinking fm is because to actualy interfear you would have to be pretty close to the reciever that was in the am mode unless you ran an ungodly amount of power and that would defeat my whole purpose of clean interfearance free medium range comunications! Within the alloted 40ch 11m!
An AM signal can and will interfere with an FM signal rather easily and you do not need to be near it to happen.as long as the AM carrier is stronger than the FM carrier it can "capture" the RX.The RX simply sees it as an unmodulated "FM" carrier. I agree with the SSB route and no it is not hard to tune a station in on SSB. I hear all kinds of people crying about how hard it is tune in an SSB station especially while mobile. I do it every day. My mobile radio only has a VFO to tune with,no preset channels.I also spend 99.999999999% of my time on SSB and I do it looking for weak DX stations on 20m and 80m all the time even from the mobile.
Hey QRN
I have always perfered SSB as well
is a bit more of a art compared to using am or fm
but is also much better for DX
i would like to work antartica
is about the only place i have not worked
Later
I have always perfered SSB as well
is a bit more of a art compared to using am or fm
but is also much better for DX
i would like to work antartica
is about the only place i have not worked
Later
C W Morse said:
CWM, just be honest here...you know it is different, right?
It would be more like if someone came into your yard and smelled your roses, not actually pull them up. You see, while they were smelling your roses, you would be deprived of their smell because they would be in your way and also be sucking up the scent. But as soon as they moseyed on, you would once again have full enjoyment of your roses.
Now, would you truely be as offended by someone merely smelling your roses as they passed by your home?