The problem is, Damir, that if you stay on the COA frequency and have a QSO, you then make that frequency unusable for others. You might invoke someone to switch on their big amplifier, turn their large antenna array in your direction and call CQ making a mess of your QSO. However, if it works for you with the level of activity in Croatia and does not cause complaint, then I suppose that is okay. It is just regarded as anti-social over here in the UK.
73, Gerald
Nobody complains for calling on 144,300. Nobody ansvers 
so I think, nobody listen.
I am ssb an cw operator. Sometimes fm. Not having hf antena at home, my activity is 2m and 70cm. So I was very interested in this topic. It helps me a lot. Thank you all for your comments and posts
I was helping my son yesterday with a school work he did about Croatia and I remember the small population, which I think it was about 4.7 millions. [edit: internet sais 4.047 millions in 2020] Thatās nothing compared to the huge UK population [edit: 67.22 millions in 2020]. The hams density in the UK requires certain behaviours that are really not necessary in less populated areas.
73,
Guru
Hi Damir, as can be seen from this thread and Johnās previous thread, many amateurs consider COAs and CC/CFs to be the same thing, a calling frequency, ie one calls on that frequency, establishes contact, agree a new QRG and then QSYs.
Others like me consider COAs to the centre of a small range of frequencies where operators using the same mode, power, speed, etc can find others. The COA frequency is not special and treated the same as neighbouring frequencies, e.g. 3.560 COA for 80m CW QRP.
Unfortunately these different interpretations inevitably lead to conflict. Re the UK 2m SSB COA (CF?), I think the quote from the RSGB VHF band plan bloke that John gave at the top of this thread illustrates the differing or confused thinking: first he gave a reason for the change from CF to COA but then says folk should treat 144.300 as a CF as he does. This blurs the distinction further.
73 Andy
Read the initial post again Andy. John SWX considers 144.300MHz to be the COA and calls +/- 5kHz. He does not consider it to be a CF. That may work for him, but in practice, the majority of us in the UK are using 144.300MHz as a CF and QSY to a working frequency so leaving the frequency clear for others to do likewise. IMHO this is another tail trying to wag the dogā¦ and (to misquote Thatcher) the dog isnāt for turning.
Well the change from a calling frequency to COA fits how we (GM13) boys (girls welcome!) have been operating. We tend to operate SSB on 2320.200MHz which was the calling frequency not too long ago. We all sit and operate on there. As of 3 years 13cms ops weāve not been asked to āmove off the calling frequencyā by a disgruntled station. Oh for that to happen!
But, the difference is there are few ops on 13cms and all activity is welcome. We regularly operate FM in the SSB section of the band. Normally a heinous crime which you would expect to be ostracised for doing so. Butā¦ we start on 2320.200 SSB and QSY to 2320.300 FM. Itās normally far enough away from .200 to be no problem. In addition most of us run 2W and along with directional aerials the QRM to other users is small. Andā¦ weāre all smart enough to know not to do that when there 13cms contests / activity days when we could cause issues.
So why do I think this doesnāt work on 2m? Well despite it being quite quiet on 2m SSB is not at all like 13cms simply becuase of the number of people with 2m equipment. Nowadays that equipment is mainly āshack-in-a-boxā radios that do 20/50/100W on 2m as well as all HF bands and the 2m port may only be connected to a white stick vertical antenna. There are still a significant number of possible users unlike 13cms.
Operate a big station (like the one SWX has) 5kHz off the COA sounds somewhat aggressive if not selfish to me as it will deny others close by the ability to use the COA for calling.
As for saying you canāt have a calling channel as SSB was not channelised is tosh. It was never a calling channel but a calling frequency. I note the RSGB bandplans have calling frequencies listed for MS on both 2m and 70cms (144.370 and 432.370). So non-channelised MS gets to keep a notional calling frequency but non-channelised SSB gets redesignated. And now someone with a big station can legitimately sit just of where most would call. Iām missing something or am being too cynical.
Gerald, I read it yet again and he does consider it a CF because he recommends that spot frequency be used for calling only and does likewise himself. If it quacks like a duck, ā¦.
I personally donāt have a view on the merits of whether 2m SSB should have a CF or a COA but if even the UK VHF band planner de facto considers it still to be a CF then it should not have been relabelled in the band plan.
Well of course the calling frequency always was the COA - some called on it and QSYd HF, others called on it and QSYd LF, so it was always the centre. Its always been sacrosanct, tooā¦
I see what you mean Andy, but this is ambiguity at its best:
Therefore, as a centre of activity you should call CQ close to 144.300MHz and it is plain courtesy to QSY if others want to use that frequency (G4SWX)
He then goes on to say that he calls 5kHz off, but does he stay there once in QSO?.Presumably not. Personally, under normal circumstances (no contest, no Es), I wouldnāt call +/- 5kHz or have a QSO there. Iāll continue to call on 144.300MHz and QSY at least 10kHz off once calledā¦ itās worked for me for the past 45 years and still does. If it aināt brokeā¦
Around here, 2m simplex of any kind, even FM, is sparse enough that one can really hold an extended QSO on a designated calling frequency without having to worry too much about tying it up. Iāve held rag chews on 146.52 (US 2m FM calling frequency) without any issue because, well, nobody is listening. Using 2m for SOTA here will only yield meaningful results on about 1 in 4 activations, even with spotting.
In VK/ ZL SOTA and VKFF operators use well known calling frequencies and standard approaches to moving after working the encumbent. If we mere Colonials can figure out a working system why canāt the EU?
We didnāt seek approval by the WIA but took note of their recommended band plans.
73
Ron
VK3AFW
Not sure of your equipment Matthew on LD 025 a summit I can work from Devon
but not if you stayed on 144.300, the so called centre of activity, what the idiots failed to realise in changing it from the calling frequency was that once doing that it gave anyone the chance to sit on it and have a qso and bearing in mind my position in the west country I will not get through that qrm. Please all when activating spot a frequency away from what was the calling frequency and give us a chance to hear you. For that reason I no longer go on the contests on vhf as also beams like always are not pointing to this way. Anyone want to buy an Icom 9700? 73 Don.
Youāre only allowed to sell it if you replace it with something else. Where would we 2m SSB ops be without the Devon beacon? 
P.S. Iāve got a spare TS-711E if youāre interested. 
Thanks for the offer Gerald of the ts-711e but the beacon will remain albeit just
a beacon if we donāt go to spot frequencies away from 300 as I do have my old trusty 847 now 22yrs old and still good and the last purchase a Yaesu ft-991a so donāt despair. 73 Don.
Actually Don itās a cunning plot hatched between the RSGB and Ofcomā¦ If they can kill off the last vestiges of 2m sideband no-one will notice when the bottom half of the band is taken off us and sold off to commercial users at vast profit :-s
There are a couple of stations in IO70 doing quite well in 144 UKAC this year, so some must be pointing their beams that way.
They gave us 146-147MHz because they canāt sell it. I think 147-148MHz is free of commercial use too. Canāt see 2m being much use for linkingā¦ too much tropo and foreign interference and todayās yoof wont want a phone with a damn great antenna sticking out of it
Itās been triedā¦
Indeed I wonāt! To think of it at one time having a 2m multimode rig was the sign of having a few quid in the bank. Now they are so common virtually nobody uses the band. Iāve got 5 separate multimode rigs that cover 2m and with the old MM transverter connected to the TS-130V, thatās 6. You could claim it is a sheer waste of circuitry. 
I see that thanks to our esteemed Moderator Brian, G8ADD this thread has made it into the VHF/UHF column in this monthās RadCom
The Editorās response is quite amusing in itās PC convolutions, but still upholds that whatever descriptor you apply to 144.300, it is plain courtesy to move off it when you have established contact 