Transatlantic 2
Andre' Kesteloot
akestelo@bellatlantic.net
Wed, 03 May 2000 07:41:50 -0400
G0MRF@aol.com wrote:
> Hello All
>
> In about 3 weeks I will be travelling from Dayton Ohio to meet Larry and
> friends in Niagara to discuss LF and in particular his plans for this
> Novembers attempt at crossing the Atlantic.
> This is a useful opportunity to ensure that, come November 10th, we are all,
> As a friend of mine from Londonderry once put it. -singing from the same hymn
> book.
>
> During the last two periods of transatlantic testing we had the luxury of
> switching the transmitters on and leaving the hard work to Andre' and friends
> on a cold wet beach on the American East Coast or recently, to Larry Mitch
> and Jack listening to static
>
> This time, with everyone eagerly anticipating a two way QSO, there is a much
> greater potential for success and a much greater chance of complete chaos.
> Hopefully we can jointly agree on appropriate operating standards and
> practice.
>
> In the past few weeks there have been a number of views expressed on the
> reflector and in private e-mails which suggest that there are a variety of
> thoughts on operating procedures for the tests. Modes, times, frequencies,
> schedules etc are all open for debate. I have been asked to arrive in
> Niagara with some collective thoughts for Larry to consider. While I'm sure
> that this discussion will eventually find it's way onto the reflector, it
> would be advantageous to have an initial exchange of views and set some basic
> guidelines prior to Autumn.
>
> Can I suggest that the following topics represent a starting point. If you
> have any views please express them, - Even if it's just to confirm the
> obvious.
> Even a brief yes / no response will help.
>
> Modes.
> We all know and appreciate the benefits of QRSS. Spectrogram is well known
> and spectran is becoming tried and tested, albeit with a small question mark
> over the jumps in the display which seem related to processor loading. Is
> QRSS the only way? Presumably optimum dot speed will depend settings and
> propagation.
> It's easy for us, but it's also possible Larry may want to trade off
> bandwidth for the ability to see more than one potential QSO on his monitor.
> Or have >1 system running.
>
> Should we try a period of very slow techniques as pioneered by G4JNT and
> G3PLX?
>
> Some stations seem determined to stick with normal CW. How / can we embrace
> this diversity.
>
> Much praise has been voiced of Bill, VE2IQ's, BPSK software. It certainly has
> the ability to operate with weak signals and the 'grab' facility means you
> could leave the station on remote ( and get some sleep) Larry has expressed
> the opinion that this can work with class D transmitters, but after the
> Puckeridge key click saga and with no practical experience in the UK at high
> power, this should be examined before any use is made of the mode.
>
> FREQUENCIES
>
> I suspect the numbers of stations participating will exceed previous levels.
>
> With CFH active, Larry will only have the top part of the band. - I'll try to
> find the limits to this when we meet.
> Larry's group will advise of specific frequencies that are clear, or
> frequencies to be avoided. This may not happen until the VO1 receive team is
> up and running. Hopefully we can devise a fair system of transmitting
> frequency allocation within a short period of time.
>
> We will only have to receive on one frequency. - So no problem there (!?)
> Should we select a frequency that's clear on the UK S.Coast as that seems to
> be the area with most QRM? Suggestions pse. Although I guess this could wait
> until the 'LF Convention' so the information is up to date.
>
> What is a minimum separation between Tx frequencies? It's important that we
> all have sufficient frequency accuracy and stability to avoid drifting into
> each other. Should we allocate frequencies so that geographically adjacent
> stations are not allocated adjacent frequencies? Or do we plan scheduled
> transmission periods. (see below)
> Do OH1TN / Europeans wish to participate. - Any indications in QSOs / e-mails?
>
> SCHEDULES.
> Some other weak signal modes run skeds that have prearranged transmission and
> reception periods. e.g. Moonbounce and Meteor Scatter.
> This has the advantage of totally avoiding QRM. You know when you switch to
> receive, you will only hear DX
> The periods used with EME and MS vary from 1minute to 5 minutes. Clearly
> this is not suitable for QRSS. But what period would be? 2 callsigns etc?
> The last time I monitored a transatlantic test it was impossible to receive a
> truly weak signal at the same time as another station was transmitting.
> Unless you are really lucky you will have someone running a lot of power
> within 50 miles. Your receiver may have an AGC which you can switch off but
> can you access the AGC in your sound card?
>
> MAKING THE QSO /S
> I guess that as your call is seen in VO1, your phone will ring! OK?
> If we take the independent approach this will not be a problem. - You just
> carry on as normal. However, If we are running synchronised Tx/ Rx periods do
> we break the receive period timing to complete the QSO? or wait for the next
> scheduled transmission period?
>
> Please feel free to copy this to other individual members of the LF community
> that you feel may be interested.
>
> Any additional thoughts? Any qustions for the VE's?
>
> Thanks for your time. I look forward to the replies.
>
> 73
>
> David G0MRF