Date: Mon, 12 May 2008 18:45:29 +0100
From: John Pumford-Green GM4SLV <gm4slv@sighthound.demon.co.uk>
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Subject: Re: LF: Re: Becons etc.
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On Mon, 12 May 2008 15:45:44 -0000
"mal" <g3kevmal@talktalk.net> wrote:

> Beacons can be useful the odd time but some are left on continuously
> for days. One weekend there was a chorous of beacons and some
> remained on for over a week just generating qrm. GI3PDN, GI4DPE,
> GM4SLV, GW4HXO and a G3 in Norfolk, cannot remember his call. I
> cannot see the necessity for this when they are all capable of
> working a two way QSO on CW, then leaving the frequencies clear for
> others. I only work two way QSO mode and QSX on 3533/7033 khz for
> replies from those without a NOV for the band plus some EU dx. I get
> lots of emails from others about beacons and some even advocate
> contacting OFCOM to have them stopped because of the QRM caused. I
> have not encouraged this approach, hoping that it will go away
> eventually. I have a couple of large antennas for 500 and 137 khz and
> these pick up the weakest signals and although good in qso mode I get
> all the beacon qrm as well hi 73 for now and I hope you now see my
> point of view.


A 250Hz IF filter and a 10Hz AF filter.... what QRM? 



The EXPERIMENTAL RESEARCH band is not for "rubberstamp DX QSOs" ("ur RST
599 = pse QSL = QRU 73") or a "ragchewers paradise" ("ere
WX sunny = been to docs for lumbago = xyl say hows Marge and the dogs?")

It's for self-determined study into a hitherto unexplored area (to
amateurs and on the whole also to professionals) of the MF spectrum. 

Before you say "the old marine CW users know all there is to know" think
again - the professional users were generally only interested in
reasonably short range, reasonably strong signals, from reasonably
efficient antennas and using reasonably powerful transmitters, over
reasonably favourable groundplane conductivity. 

Very little could be done during the heyday of MF CW to
seriously investigate this region of spectrum, in terms of compromise
short antenna systems, weak signals and anomalous propagation -  due to
the high levels of occupancy and large signal levels. 

Certainly nothing was known at that time about DSP and clever digital
modulation/coding systems to achieve robust, low power, information
exchange. 

YES.... I know... "CW IS BEST".... but think... some of the new schemes
may actually be BETTER.... but until someone tests them we'll never
know..... CW might indeed be the one true mode, let others do their
datamode tests, and let's see.


Randomly convened 2-way CW QSOs may provide an insight into the
band, for the 2-stations concerned. It's a bit hit and miss though.


However others may want a more in depth, scientific view of things.

Long periods of transmission (I'm not going to call them beacons) allow
the collection of much more data, by many more people, than the odd
"I've got half an hour to spare, let's see what's on 500" way of
operating 

I have had many CW QSOs on 500 where some actual experimentation was
done in the course of the QSO but in generalI think most QSOs are
either local groundwave rag-chews or short (what's to be learned by
this?), or short rubber stamp "DX" QSOs - to get a new
call/country/distance in the log. 

Are you telling me that this style of operating is what was intended by
the issuing of Special Research Permits? 

Admittedly the research concerened may be to build/modify/adjust the
equipment, and the QSO is a means of proving a concept or validating a
modification etc...


The "beacon hell" period you refer to, where several stations had
continuous CW idents running, was for a specific and I think valid,
cause - to enlist the community of NDB listeners (experts in narrow
band, weak signal in high QRM, MF CW reception) over the Easter weekend
in attempting to receive amateur signals on 500kHz.

We all got very many reports - many more than could have been gathered
relying only on direct, in-band or cross-band QSOs.


The stations sending the transmissions learned much about the
performance of their equipment, and the band itself, and the listeners
probably gained new knowledge too.


I'm heartily tired of all this whinging about "beacons are spoiling
it".

Do you want to turn the radio on, call "CQ", have a QSO with a random
stranger?

Use 80/40/30/20m.



Do you want to study something specific, in depth? 

Then do some more structured operating. If this is pre-arranged regular
skeds with specific stations (the dreaded email...to arrange them,
to report on them beyond what is passed in the QSO... to discuss things
- eg  if it failed due to unsuitable conditions.....)


Or even generate a more general "beacon" (attended operation only of
course!!!) for a wider audience to study. Perhaps operate a grabber
for others use as a research tool...


These are more in line with the spirit and intention of the Special 
Research Permit than random QSOs.



Your narrow view of how others should operate on 500, repeated ad
nauseum on this list every time you get out of bed the wrong side, has
driven several experimenally minded people away already.... and now
it's done the same for me too.


I'm now QRT on 500 and I know you'll be happy at that. More proof that
the modern radio amateur is a technically challenged appliance
operator. You're wrong in that assumption - my operation on 500 has
been with homebrew gear and manual telegraphy only - but you're
welcome to your opinions (you certainly have plenty of them). 


For those that used my grabber for their investigations, or were happy
to study my "beacon" signals from this far flung corner of the UK - I
wish you every success on 500. 

Just make sure you play by Mal's rules.

Regards,

John Pumford-Green
GM4SLV