I can not say I have. I just have not had time to get on much latley to hear anything. Just got some coax hooked back up in the shack.
Going to be playing around with some am shortly. I will be using a Heathkit Apache.
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Question About Using AM mode on HF
- Thread starter Sonwatcher
- Start date
I can not say I have. I just have not had time to get on much latley to hear anything. Just got some coax hooked back up in the shack.
Going to be playing around with some am shortly. I will be using a Heathkit Apache.
Is a joke somewhere about where the Swan-net meets, and the Swan 3drifty, but to answer your question without some divine intervention yes they do drift
That would be the Swan TooDrifty, I believe. If you are looking for the freq they meet on, just wait around and they will drift by soon.LOL
Wow, I didnt know I said at 100% you would flat top....maybe your problem is reading comprehension!!
HI DEF: You are correct, about the Asymetrical aspect but your numbers are a bit off. assuming your talking about class C.
So as to save on typing, I posted this in another thread also, A very good read!!!!
Amplitude Modulation
The FCC deliberately deleted the old mode designators and has replaced them with the words good engineering practice.
Bandwidth cannot be described as an absolute like a lot of hammy hambones like to do. Some slope always exists in an analog system. So do close-in distortion products.
Those old A3E type designators were generic.
Anytime analog bandwidth is discussed it should include a dB figure for roll-off.
Otherwise it's meaningless.
Or perhaps, like most Government employees you simply lack any sort of communication skills....
And no, you didn't say at 100%, you said the following....
And the other
I suppose I knew what you meant but many readers would not, whether your a knowledgeable individual, or an inarticulate individual that has issues being precise.
perhaps take your own advice?
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See what I mean about opinions? It's sort of odd, do you also classify quite a few electrical engineers as "hammy hambones"? That's where those 'generic' mode classifications came from you know, wasn't us "hammy hambones" that thought up those thingys. But if it makes you feel better to blame them/us "hammy hambones", be my guest.
I gotta go clean some of those opinions off my house-shoes, can't let that stuff build up, it'd never come out.
- 'Doc
I gotta go clean some of those opinions off my house-shoes, can't let that stuff build up, it'd never come out.
- 'Doc
The opinion that matters here is the one used by the FCC.
Engineers deleted those mode classifications. They were most likely competent engineers who recognized hobbyists cannot measure occupied bandwidth. Many can't grasp the concept and prefer to make it into some sort of personal crusade.
:bdh: My HAM friend and I try all sorts of bands in AM mode and you have to adjust the rig just right and the sound is just classic! We even use AM on two meters, I have yet to find anything against that! and it too sounds great....
If you think about it CW is a simpler form of AM and I have "keyed" an AM CB with no modulation and made all sorts of contacts.... But that is fodder for a different post!
mechanic
If you think about it CW is a simpler form of AM and I have "keyed" an AM CB with no modulation and made all sorts of contacts.... But that is fodder for a different post!
mechanic
no, the emission designators still exist and are referenced in part 97.
this is standard ESSB strawman answer, "hobbyists cannot measure occupied bandwidth."
the correct answer is in 97.307 (a) & (b).
(a) No amateur station transmission shall occupy more bandwidth than necessary for the information rate and emission type being transmitted, in accordance with good amateur practice.
(b) Emissions resulting from modulation must be confined to the band or segment available to the control operator. Emissions outside the necessary bandwidth must not cause splatter or keyclick interference to operations on adjacent frequencies.
and yes 97.307 (d) does state specific Db attenuation factors, but the bottom line is that it DOESN'T have to be exactly measured. read 97.307 (b) again.
op:op:op:Exactly...if you are unable to measure your bandwidth, you certainly are incapable of measuring the quality of your signal...which you are responsible for, no matter what the FCC wording is.
The new wording only means you are responsible for your signal even more than before. The attitude that this means it is now a free for all, is exactly the problem that people bitch about with regard to less than clean or excessively wide signals. Either users don't care that they are interfering with adjacent traffic, or they don't know any better...which is just as bad if a user is using modified transmitters without knowing any better.
It is not o.k. to have 20kHz of signal energy simply because you don't know any better and the FCC isn't regulating bandwidth specifically. You will certainly interfere with others on the band if you are over 10kHz or even at 10 if outside the gentleman's agreement for AM channelization on the bands.
Improperly run AM or modified/home brew transmitters on AM can be a massive source of interference. Far worse than even the worst SSB I've seen on the bands.
A lot of the worst AM operators don't even realize it has two sidebands...so they never check up AND down from where they put the carrier. Then they sit and bitch that someone just encroached on their frequency....when they were in the USB of their carrier all along.
The new wording only means you are responsible for your signal even more than before. The attitude that this means it is now a free for all, is exactly the problem that people bitch about with regard to less than clean or excessively wide signals. Either users don't care that they are interfering with adjacent traffic, or they don't know any better...which is just as bad if a user is using modified transmitters without knowing any better.
It is not o.k. to have 20kHz of signal energy simply because you don't know any better and the FCC isn't regulating bandwidth specifically. You will certainly interfere with others on the band if you are over 10kHz or even at 10 if outside the gentleman's agreement for AM channelization on the bands.
Improperly run AM or modified/home brew transmitters on AM can be a massive source of interference. Far worse than even the worst SSB I've seen on the bands.
A lot of the worst AM operators don't even realize it has two sidebands...so they never check up AND down from where they put the carrier. Then they sit and bitch that someone just encroached on their frequency....when they were in the USB of their carrier all along.
no, the emission designators still exist and are referenced in part 97.
this is standard ESSB strawman answer, "hobbyists cannot measure occupied bandwidth."
the correct answer is in 97.307 (a) & (b).
(a) No amateur station transmission shall occupy more bandwidth than necessary for the information rate and emission type being transmitted, in accordance with good amateur practice.
(b) Emissions resulting from modulation must be confined to the band or segment available to the control operator. Emissions outside the necessary bandwidth must not cause splatter or keyclick interference to operations on adjacent frequencies.
and yes 97.307 (d) does state specific Db attenuation factors, but the bottom line is that it DOESN'T have to be exactly measured. read 97.307 (b) again.
Please show me exactly where Part 97 quotes phone BANDWIDTH numbers of any kind.
The bands are loaded with poor operators on all modes.
Dunno where all those AM guys who don't know about their upper sideband are. I hope I never find out.
I suggest you might want to let these guys know about this on the air.
There are all too many because it is too easy to just push the "AM" button. The mailing lists for various rigs are loaded with people constantly asking for the service menu keystrokes to get the power up to 100W for AM as well.
I like AM mind you...just sayin. 75m in NE region has been loaded with ops randomly firing up AM in the weirdest places. 3.805 with a bunch of General class licensees was a recent entertaining one.
If you don't have an SDR receiver yet, get one. It's endlessly amusing to be able to see signal qualities across an entire band or 100kHz at least at a time. I can see how bad someone's signal is 200+kHz away from where I'm tuned...and yes, I often politely explain if someone has a bad signal, but they have to have enough understanding to care too.
Without a doubt there are bad signals of every kind, from digi modes through AM. AM is just a lot wider so when it's bad...it has a farther reach.
Worst SSB signal of a regular operator that I've seen so far is roughly 12kHz. 3kHz for the main signal, about 6 more down the band to the lower sideband and 3+ into upper sideband. Guy is a daily operator who has been told many times. My bet is he is running a class C CB amp into full compression.
Worst AM signals I've seen so far are home brew transformer modulated with voice signal energy at 10kHz, but significant (maybe 10dbm down from the carrier level) splatter out another 10 in either direction.
