Mal,
In the US we have very few operators spread out over a large
geographic area (including ops in Alaska and Hawaii) as well as up to
20kHz available to us. To date QRM is a non-issue.
--
73 Warren K2ORS
WD2XGJ
WD2XSH/23
WE2XEB/2
WE2XGR/1
On Thu, May 6, 2010 at 1:43 PM, mal hamilton <[email protected]> wrote:
> The majority of CW operators on LF/FMF will not exceed 100 hz bandwidth.
> 99.9% are sending at speeds of about 10wpm or less.
> 100 hz is about right on LF/MF where the total bandwidth of the permitted
> allocation is about 3 khz
> also, as far as data modes are concerned all that is happening on LF/MF is
> bodging data modes meant for vhf/uhf applications and making a mess, ie the
> Appliance Operator approach
>
>
> g3kev
>
>
>
> ----- Original Message -----
> From: Rik Strobbe
> To: [email protected]
> Sent: Thursday, May 06, 2010 1:19 PM
> Subject: RE: LF: 500 Permit emission’s bandwidth? EU and Global ??
> Graham,
>
> the document that gives us access to 500kHz says 100Hz bandwidth, but does
> not say how many dB's the signal has to be attenuated at these limits.
>
> 73, Rik ON7YD - OR7T
>
> ________________________________
> Van: [email protected] [[email protected]]
> namens Graham [[email protected]]
> Verzonden: donderdag 6 mei 2010 13:30
> Aan: [email protected]
> Onderwerp: Re: LF: 500 Permit emission’s bandwidth? EU and Global ??
>
> Ok Many thanks' for the reply's
>
> From that .... next is :-
>
> From the data, I assume that 100 Hz is the common limiting factor for
> a narrow band data transmission that could be used by all who
> 'wanted' to use it ?..(noted on the cw keying speed ~ BW)
>
> So if a value of 100 Hz is specified, what is the 'presumed' roll-off
> of the power in the said bands ?, assuming that the original concept was
> based on CW operation , which by definition 'has to' generate sidebands ,
> there must be an assumed tolerance ?
>
> Q would the deployment of a system that could defined as 125 hz
> bandwidth ie 100 Hz with +/- 12.5 Hz overspill , cause a technical
> breach of the regulations or be viewed as occupying the 'allocated'
> bandwidth for a telegraphy transmission ? ,
>
> Taking that spectral measurements in the 10 Hz region are perhaps
> starting to test even the best equipment, the area is perhaps a
> little empiric ?
>
> I use the word telegraphy, purposely to view/observe the situation
> interims of the licence conditions and not on the basis of 'mode' which
> like Liverpool and Everton have there own sub cultures but are still
> football teams ..
>
> Thanks
>
> Graham
> G0NBD
>
>
>
>
> From: Graham
> Sent: Wednesday, May 05, 2010 10:39 PM
> To: [email protected]
> Subject: LF: 500 Permit emission’s bandwidth? EU and Global ??
>
> 500 Permit emission’s bandwidth?
>
>
>
> Can any one indicated what is the permitted ‘telegraphy’ bandwidth of
> the various ‘new’ 500KHz licences or special permits issued round the
> EU and now the rest of the Globe ?
>
>
>
> I have the impression that 100 Hz is the maximum ‘telegraphy’ transmission
> bandwidth, in some cases, eg , Belgium at 100 Hz . Others appear to be some
> what wider or not defined ?.
>
>
>
> Norway is CW only ? what is the Dutch allocation ? Southern Ireland ?
> ... etc
>
>
>
> Are Beacons defined by mode or bandwidth ?
>
>
>
> Tnx – Graham
>
> G0NBD
>
>
>
> (I use the word ‘telegraphy’ as defined by the ITU R V.662-3 , please
> no reference to key clicks ! )
>
>
>
>
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