Content-Transfer-Encoding: 8bit
From: "flo flo" <hellozerohellozero@hotmail.com>
To: rsgb_lf_group@blacksheep.org
Date: Tue, 12 Aug 2003 12:41:50 -0800
MIME-Version: 1.0
Message-ID: <Law15-F3hpAXwxGGRVs0004b0c9@hotmail.com>
Subject: Re: LF: Re: Re: BBC R4 LW "Frequency Standard"
Content-Type: text/plain; charset=iso-8859-1; format=flowed
Sender: <owner-rsgb_lf_group@blacksheep.org>
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org

...and R4 is pretty weak here in Alaska  too compared with its Eureopean 
counterparts across the Marche/channel (often some 20-30 dBs stronger) - Ive 
only managed to listen to cricket test match special on a few occasions - 
and the freq is shared in an NDB Canadian Beacon some 600 miles south too 
which doesnt help.

R4 LW 198Khz  in Aberdeen Scotland was appauling - and that why they had a 
MW relay...AM phase and all that...

Given the Power differences in some of the European LW  stations R4 is very 
much weaker than I would have imagined here, but, there are more than one 
variables that influence signals quality and strength. I presume the R4 LW 
station doesnt "beam" or does it?

Given the "speed"/sheer of the particles in the ionosphere - and they would 
have to be moving quite fast; might we not see some blurring of phase from 
the two locked sources?

Beacon

...and the WD2XDW beacon will be on from 0001Z on around 137.773Khzish until 
advised. I might get the locked freq source sorted tonight. The matching 
system is now under cover and no deterioation of aerial current has been 
seen. Around 2.3 amps.


Laurence - rainy Anchorage

>From: "Alan Melia" <Alan.Melia@btinternet.com>
>Reply-To: rsgb_lf_group@blacksheep.org
>To: <rsgb_lf_group@blacksheep.org>
>Subject: LF: Re: Re: BBC R4 LW "Frequency Standard"
>Date: Tue, 12 Aug 2003 20:30:48 +0100
>
>Hi Hugh, yes I supose it would have some effect. The advantage is that all
>the transmitters are under "atomic" control so there is almost a continuous
>phase difference between their carriers. The "mush" area, I think, refers
>mainly to the reception and demodulation of the AM program material. I
>suppose within ground-wave range there is "beat" when the strengths from
>Droitwich and say Westerglen are approximately the same ....the beat
>frequency would not more than 0.00001Hz or about 1 cycle in 30 hours (I 
>hope
>my thumbnail calcuation is right....but I sure someone will tell me if it
>isn't). I dont expect that would give much problem but the path differences
>from the different tranmitters might give some interesting effects at
>distance. The only person I know who does monitor R4 is Laurence in
>Anchorage.
>
>Cheers de Alan G3NYK
>alan.melia@btinternet.com
>
>----- Original Message -----
>From: "Hugh M0WYE" <m0wye@thersgb.net>
>To: <rsgb_lf_group@blacksheep.org>
>Sent: 12 August 2003 16:21
>Subject: LF: Re: BBC R4 LW "Frequency Standard"
>
>
> > Hi Alan, Group,
> > Interesting article about BBC R4 LW.
> >
> > Does the fact that there are multiple transmitters on this frequency 
>have
> > any bearing on those who might use the 198kHz signal as a propagation
> > indicator outside of the UK ?
> >
> > Presumably the interference pattern ("mush area") extends way beyond our
> > shores, and someone monitoring, say in the 'States might receive a weak
> > signal, not because there was no propagation, but because the two
> > transmitters happened to be in cancellation.
> >
> > I assume the signals that we might use for reference, such as DCF39, 
>have
> > only one source.
> >
> > 73
> > Hugh M0WYE
> >
> > ----- Original Message -----
> > From: "Alan Melia" <Alan.Melia@btinternet.com>
> > To: "LF-Group" <rsgb_lf_group@blacksheep.org>
> > Sent: Tuesday, August 12, 2003 3:57 PM
> > Subject: LF: BBC R4 LW "Frequency Standard"
> >
> >
> > > Hi All, I have posted the latest DTI Time & Frequency Club Newsletter 
>to
> > my
> > > web site. It contains a short description of the frequency control of
>the
> > > BBC Radio 4 Longwave  transmitters on 198kHz, together with details of
>the
> > > phase modulation data service it also carries on the carrier. This 
>will
>be
> > > interesting information for those of you who, like me, may have a 
>198kHz
> > > off-air standard in your workshop.
> > >
> > > Download of the 68kB pdf file is available from the link in the 
>contents
> > > section on the index page.
> > > http://www.alan.melia.btinternet.co.uk/
> > >
> > > Cheers de Alan G3NYK
> > > alan.melia@btinternet.com
> > >
> > >
> > >
> > >
> >
> >
>
>

_________________________________________________________________
STOP MORE SPAM with the new MSN 8 and get 2 months FREE*  
http://join.msn.com/?page=features/junkmail