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[CQ-Contest] ARRL 10 Meter / Geminids 2019 / Scatter tips

To: cq-contest reflector <cq-contest@contesting.com>
Subject: [CQ-Contest] ARRL 10 Meter / Geminids 2019 / Scatter tips
From: Dave K2XR via CQ-Contest <cq-contest@contesting.com>
Reply-to: Dave K2XR <k2xr@ptd.net>
Date: Thu, 12 Dec 2019 18:27:55 -0500
List-post: <mailto:cq-contest@contesting.com>
Q:  When is a black hole not a black hole ?

A: When the black hole is the center of the USA during a meteor shower peak.

This year CQWW CW fell on the weekend before Thanksgiving.  A rare occurrence indeed.  Another interest thing happens when this occurs.  The peak of the Geminids meteor shower will coincide with the two nights of the ARRL 10 meter contest.

VHF contesters regularly use meteor scatter as a means to work stations as far away as 1500 miles.  The same technique is used every year by a small percentage of the 10 Meter ARRL participants to increase their scores.   During years of high solar activity, such methods and practices are of little additional benefit and the method is overlooked for the most part.  However during solar minimums, 10 meter openings are fewer, further between, and tend to be North South in nature in general.  This means you should use Friday night until Saturday Sunrise to work as many stations on meteor scatter (MS) as possible in the event that 10 meters never opens properly.

    Most operators are familiar with sporadic E openings.  They peak around the end of June, so ARRL field day results in many good 10 and 6 meter openings using that mode.   There is also another peak of sporadic E events in late December and dx cluster spots this month already are showing  those openings.   In the northern hemisphere June is better than December and in the southern hemisphere vice versa, but the peaks are reliable and independent of solar activity.

Why mention all that ?    Simple,  all your hard meteor scatter efforts to work stations to the east or west of you can be wiped out by a sporadic E    IF:

1- it occurs at all

2- lasts long enough for operators to discover it and utilize it.

But this year could be different than most in the past.  First we are presented with some of the worst solar activity in our lifetimes.  This makes the chances of a proper E layer opening less than usual.  According to prediction programs like VOACAP Long distance North South trans-equatorial paths are very like to open, but shorter paths not so much.

So it is probably a good idea to count on making MS contacts the first night. Then you can decide whether the second nights MS effort is worth it based on Saturday daytime results.

Meteor Shower resources.

The Geminids are one of the most active and reliable meteor showers of the year.  In my lifetime the activity level of this shower has been steadily increasing.  Researchers report that the gravitational field of Jupiter is concentrating the debris field result in a much sharper peak count than in the past.    The current published rate of meteors to be expected at midnight local time is 100 or more per hour.  In addition Geminids tend to be the biggest and brightest visually.   Unfortunately for visual spectators, the full moon of 12 December will greatly decrease the visual count and apparent brightness of the meteor trails.   Lucky for us hams, the full moon will have no effect on the ionized trails of the burning meteors, which is what we are reflecting our radio waves off of.

To listen to a live steam of meteor activity,  try this website from  sunset to sunrise.

http://www.livemeteors.com/

Also at that website is an excellent explanation of the methodology of MS reflections of radio waves.   The audio at that site is from a 60 megahertz signal.  Why this matters ?   If you hear a 5 second burst on that site, the length of the burst on 10 meters will be 4 times as long, or 20 seconds.    Plenty of time for a complete QSO.      Last night (Wednesday)  I was seeing many bursts in the 30 - 60 second range ....   That would be an opening on 10 meters of 2-4 minutes in length.   Many QSO's can be made in that time period, and that was Wed.  not even close to the peak which will occur during the contest.   That is why I said it may be the event of a lifetime for MS contacts.  The band may appear to be open continuously or very close to it.     But

*It will all be for naught if all of us aren't there to take advantage,  so be there or be square*.

For those interested in viewing the meteors from the warmth of indoors.  5 live cameras are available at this site.

https://amsmeteors.org/live/


*TIPS AND TRICKS FOR MAXIMUM QSO's*

*KISS
*

Keep it short and sweet.   Time is of the essence.  keep CQ's short and often .   Once a burst starts, if both sides realize it and take advantage, the QSO takes seconds.    If you have to wait for the next burst to occur to complete a partial QSO, it can get very lengthy.

*RX FILTERS*

Avoid using narrow filters  use your SSB filters whether you are on SSB or CW

The speed of the meteor causes a doppler effect on the received signal.  Some ops call it a scream ...  whatever you call it, narrow filtering on CW can cause you to lose otherwise copyable characters. Also many times while you are working one station, you can also be lining up another on an adjacent frequency.   It is an acquired skill, but with narrow filtering, you will never hear it in the first place.

*FREQUENCIES*

Stick to whole kHz values unless the band gets really crowded .. Start by using even numbers of KHZ     28.002 28.004  28.006 .... and on up

On phone  start at 28.400  and stick to 5 khz steps from there in both directions.        .....  28.385  28.390 28.395 28.400 28.405 28.410 28.415  ......

*CLUSTER FILTERS*

Maintain a different filter for nighttime use.  Ideally it would takes spots from anywhere, but only post spots from a 1500 mile radius from you.  There are many ways to achieve this.  But here are some general recomendations.

Do NOT use skimvalid as an argument.  Very likely that only one skimmer will hear any given station.    Those with skimmers deployed to other bands due to lack of 10 meter openings might consider deployment to 10 meters for the event.

If you are in the USA  and using an AR6 node for RBN CW      : after sending your filter, issue  the command

SET DX EXTENSION STATE

only need to do that once

  This will add the STATE  to the spot so you can determine if the spot is in your 1500 mile range.     ( I am on the US east coast and writing from that vantage point )    the meteor shower is a world wide event so your filters will vary from mine.

mine will be

set dx filter  (freq > 28000 and freq < 29000)  and spottercty = [k,ve] and (not comment=[*beacon*,*NCDXF*])

This filter is close to ideal for the US Black hole, and they are indeed ideally situated for this event this time.

Stations in Eu will want to modify it totally.    If you are single mode, then modify the frequency range to suit.

This will allow your bandmap / available window to fill with stations in the desired region whether you can hear them or not. Go to the frequency and wait for a meteor to happen.      I will be there, hope you will be too.

Don't forget to revert to your regular cluster filter in the daytime !

PLEASE SPOT EVERY STATION YOU HEAR OR WORK or find as a dupe but not on the bandmap.   Thanks a meg and GL in the contest.

      Dave K2XR

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