[South Florida DX Association] ARLP006 Propagation de K7RA

[Bill Marx]

 SB PROP ARL ARLP006
> ARLP006 Propagation de K7RA
> 
> Our sun is very quiet. The daily sunspot reading was 0 each day from
> January 29 through February 7. The last time we saw ten consecutive
> days with a sunspot number of 0 was way back on the other side of
> the solar cycle, from December 24, 1996 to January 3, 1997. Prior to
> that, from September 13, 1996 through October 20 1996 were 38 days
> with a sunspot number of 0. Perhaps a year from now we'll again see
> a whole month with 0 sunspots.
> 
> Compared with last week, the average sunspot number declined over 7
> points to 1.7. Average daily solar flux was down over 4 points to
> 76.
> 
> Sunspot numbers and solar flux should rise over the next few days,
> but not by much. Geomagnetic conditions also look quiet, with the
> next period of high geomagnetic activity set for February 22. This
> is based upon the previous rotation of the sun.
> 
> A fascinating email arrived this week from Larry Putman, WB3ANQ of
> Pasadena, Maryland. He described working VK6DI in Western Australia
> on 30 meters using very slow-speed CW, running only 961 microwatts.
> That is under 1 milliwatt, over an 11,558 mile path. Larry used an
> old Hewlett-Packard HP-3336 signal generator as a transmitter
> feeding a 30 meter half-wave inverted vee dipole. To achieve the low
> output power and measure it precisely, he used a precision
> attenuator and measured the signal with an HP-3586C Selective Level
> Meter.
> 
> But Larry didn't depend on the station at the far end to copy by
> ear. The CW was sent in QRSS mode, which has a very slow rate of as
> little as one word per minute or less for weak signal work. The CW
> was pulled out of the noise by feeding the audio into a computer
> sound card, and detecting with ARGO software.
> 
> You can see info on this mode of communication at,
> http://www.ussc.com/~turner/qrss1.html, and Larry's operation is
> detailed on his web site at, http://www.wb3anq.com/.
> 
> You can see the web page of VK6DI on the receiving end at,
> http://www.users.on.net/~davroz/vk6di.
> 
> Details on ARGO software are at, http://www.weaksignals.com/, and
> see the efforts of a group called the QRSS Knights at,
> http://www.cnts.be/knights_qrss/.
> 
> Also check out ON7YD's page on extreme narrow band techniques at,
> http://www.qsl.net/on7yd/136narro.htm.
> 
> This mode is also used on longwave VLF operations, and you can see
> information on this at, http://www.lwca.org/.
> 
> If you would like to make a comment or have a tip for our readers,
> email the author at, k7ra at arrl.net.
> 
> For more information concerning radio propagation and an explanation
> of the numbers used in this bulletin see the ARRL Technical
> Information Service propagation page at,
> http://www.arrl.org/tis/info/propagation.html. An archive of past
> propagation bulletins is found at, http://www.arrl.org/w1aw/prop/.
> 
> Sunspot numbers for February 2 through 8 were 0, 0, 0, 0, 0, 0 and
> 12 with a mean of 1.7. 10.7 cm flux was 77.3, 78.7, 77, 76.3, 74.9,
> 74, and 74, with a mean of 76. Estimated planetary A indices were 3,
> 4, 4, 3, 12, 4 and 3 with a mean of 4.7. Estimated mid-latitude A
> indices were 1, 3, 3, 3, 11, 4 and 2, with a mean of 3.9.
> NNNN
> /EX
> 
>