[VHFcontesting] Auroral propagation
Tom & Martha
mtnest at hartcom.net
Thu Aug 5 18:02:46 PDT 2010
If you haven't heard Aurora on 2 meter CW....it sounds like someone sending cw via snare drums.....or trying to send cw
with your mouth by hissing the morse code. If the 'Au' is strong enough, it is possible to communicate via SSB but it is
not easy and is time consuming.....cw is MUCH more effecient.
And one last thing....if you do get involved in an 'opening' the report is RST style as you might imagine, where the RS is as usual
but the 'T' portion is an A to represent an 'Auroral' tone. So, for instance, an RST of 599 under normal conditions would be
sent as 59A during an aroral 'event.
If you are lucky enough to get involved in an auroral event, it is something you will not forget !!!!!!!!!
> Date: Tue, 3 Aug 2010 11:50:32 -0700 (PDT)
> From: Paul rollinson <ke1li at sbcglobal.net>
> Subject: [VHFcontesting] Auroral propagation
> To: vhfcontesting at contesting.com
> Message-ID: <652321.77727.qm at web81603.mail.mud.yahoo.com>
> Content-Type: text/plain; charset=us-ascii
> OK...... I'll fess-up. This is a new propagation mode for me and with a
> potential storm I have some questions.
> What are some productive methods for working this mode?
Concentrate on 6 meters if the signals are very weak. Move to 2m when signals
are strong on 6. Try 222 also. 432 is possible, but for contesting purposes is
not productive. If you're working tropo and you think you hear a buzz on a CW
signal, aim your antenna north to see if the aurora has started. Sometimes
off-direction tropo sounds vaguely like aurora (multipath distortion) so don't
jump to conclusions. Just like any other propagation mode, call CQ a lot
and tune the band for signals. Also be on the lookout for auroral-induced
Es during and after the event. There can be doppler shift, so use your RIT
to tune for callers when calling CQ on CW. If you're calling someone and they don't
come back, they may not know that trick so try calling them .5-1.5 khz above
and/or below their frequency. 144.2 can become a cacophony of hisses from
everyone trying to use the same frequency so s-p-r-e-a-d o-u-t. Speaking of
spreading, CW signals are spread out also so allow more room for adjacent
stations than you normally would.
> What emission mode is best for aurora(CW/USB/WSJT)?
On 6 meters, CW and SSB. On 2 meters, CW only. Distortion can get so
severe on 6 meters that it may be necessary to switch to CW. There will be
too much distortion for most digital modes to work.
> Can you expect enhancement from CME events?
Not all of them. and you don't necessarily need a CME to have aurora.
> I've been told its best to point north to work aurora propagation. Does it
> matter if I'm west or east a few degrees?
Aim toward your magnetic north (I think it's close to north in FN41). And
yes, swing the beam for maximum signal strength. The optimum direction
will change as the aurora shifts around. Stations east of you will generally
be stronger with the beam slightly to the east, ditto for west. If the aurora
is especially strong and moves overhead (which won't happen too often in
FN41) you may need to point the beam west or even south of west! Don't
forget to go outside and admire the light show when that happens, it's very
> All feedback welcomed.
> Paul, KE1LI
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