10m Band Calling Frequencies.
On the UK 10m band FM there is defined calling frequency. On the 10m AM there is not a defined calling frequency. Is there a non official calling frequency which amateurs use when putting out QSO's or is it the case of roaming up and down the bands and hope someone is listening or calling?
Last edited by Sudden; Tue 10th Apr 2012 at 20:21.
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I've always had remarkably good luck in calling a CQ if I suspect the band's open. I make my own "calling frequency" after making sure no one else is using it.Originally Posted by Sudden
On the UK 10m band FM there is defined calling frequency. On the 10m AM there is not a defined calling frequency. Is there a non official calling frequency which amateurs use when puuting out QSO's or is it the case of roaming up and down the bands and hope someone is listening or calling?
73
Pat K7KBN
Semper ubi sub ubi.
In the USA 10 Meters AM is not an option.
Our band plan - Gentlemens Agreement says that everything below 20 meters shall be Upper Side Band SSB.
Everything above 20 meters is Lower Side Band LSB SSB.
When you do not follow the band plan, you mess up the bands for everyone else.
Let me explain.
With Single Side Band communications, the carrier is on the frequency you are dialed into and the Intelligence - modulation extends about 5 - 10 - 15 Khz above or below the frequency you desire to operate on, depending on if it is USB - the intelligence is higher then the carrier, or LSB where the intelligence is below the carrier.
That is the reason why you must stay at least 3 KHz below or above the band edge when you transmit.
Now - if everyone is on say 28.400 USB - their bandwidth extends about to 28.4235 USB and hopefully does not go below 28.3985 MHz.
When we don't use amplifiers - we use less bandwidth, which makes us better neighbors in the ham radio community.
If we switch to LSB on 28.400 - now our bandwidth is about 28.3975 mhz and up above 28.4025 mhz and the people trying to use 28.395 and the people trying to use 28.400 and the people trying to use 28.405 are all displaced because your modulation is going the wrong way and the people trying to use the bands are now hearing you in both directions, both the same direction as everyone else and the people in the opposite direction - which would have had one more useable frequency, but doesn't because you are occupying too much bandwidth.
Now add to the confusion Amplitude Modulation.
Am - neither side of the band is suppressed, which means that the people down on 28.395 and the people up on 28.405 can both hear you if you are running enough power to transmit far enough to be heard.
Just remeber to read my last post, where I said that I talked 28.415 MHz USB from Pennsylvania PA USA to Gibralter Spain with 25 watts, or that I talked from Pennsylvania to California and the other person talked back to me with 5 watts.
10 meters does not require a lot of power.
As a matter of fact, when running 10 meters, a little amplification - 100 - 300 watts improves your signal a lot.
Using more power - say 1000 watts or more - doesn't do a darn bit of good, just makes your signal wider and your modulation louder.
Does it matter how loud your modulation is?
As long as I can hear you and you can hear me what is the point?
The point is - the contesters wants to be loud, because just like the Pied Piper in the childhood tales, the man with the flute that makes the noise is the person that the rats follow.
When people hears you and you are loud, they are attracted to you because they think that you are important and they want to talk to you, even if it is just to get your call sign adknowledged.
When in fact their signals are excessively wide and usually they occupy more bandwidth then necessary and that makes them look bad to any real ham radio operators - who knows that the rules says that you should use the least amount of power necessary to make your transmissions - not the most.
When a person acts the fool, then you take up precious bandwidth which real operators could have used to make their contacts also.
Probably the reason why Field Days operations are supposted to be ran at 150 watts or less power and long wire antenna's and alternate power sources, because when there is a actual emergency - once the power goes out, the power that you have left, be it a batter bank or emergency generator, is not going to last long on a couple of hours of stored power or a couple of gallons of gasoline.
Remember - when the power goes out, the gas stations can no longer pump gasoline, so every drop of gas and every watt of power that you can conserve - will keep you on the air longer and will make you more valueable as a ham radio operator in a emergency situation.
Last edited by AB3NK; Mon 17th Oct 2011 at 11:32.
Or band plan calls for two main calling frequencies - which are both Gentlemens Agreements 28.400 MHz USB and 28.425 USB.
Unfortunately there is not a lot of gentlemen around to enforce this.
When there is a contest, there is always one or two idiots that insists on using those frequencies for their contest.
They sit there and cluck like chickens and refuse to leave.
You do have regular AM nets on 80M, I believe at the high end which we don't have access here to in the UK. We have regular AM activity here on 3.615 MHz, but used sensibly due to the wider bandwidth, i.e. not after dusk. There are also some very nice 50W class E transmitter kits available here that is increasing the use of AM. I'm working on an AM modulator for an old 1950's 150W DC input cw transmitter that I'm restoring, replacing perished screen cables. AM certainly hasn't died out.
Steve M0SVB
And I think you've got things a little backwards there - Above 10MHz is USB and below is LSB, not the other way round.
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