A beacon that sends continuous CW v's has been heard for years on 7.002,
mostly during the winter. At rare times it ID's on CW as RCQ45. The signals
appear to be coming from the UL7/UA9 area.
The beacon is becoming copiable around 1130z long path and around 0100z
short path in Missouri. This evening it was quite strong.
For the past year I have been logging appearances of the beacon and
tape recording some of its more interesting variations.
Does anyone have any info or comments about this highly useful ( for
DXers) beacon? Anyone have ideas about its purpose? Where do you think it's
located?
I am especially interested in comments from listeners in Europe/Asia.
Jeff Singer K0OD jfsinger@delphi.com
>From bhorn@netcom.com (Bruce Horn) Sat Sep 10 06:38:49 1994
From: bhorn@netcom.com (Bruce Horn) (Bruce Horn)
Subject: Antenna Near Fields
Message-ID: <199409100538.WAA10488@netcom9.netcom.com>
When I was preparing for my public hearing in Los Angeles as part of
the approval process of erecting a tower that exceeded the normal
height limitation, one of the issues I examined was the field strength
as a function of distance for different antenna heights. The following
data was calculated using K6STI's AO antenna modeling program to
calculate the peak near electric field (V/m) for a 4-element 20-meter
yagi on a 32 foot boom at 14.2 MHz. The boom lies along the x-axis,
with the positive x-axis being the direction of antenna gain. The
origin is the point on the ground under the center of the antenna. The
near field was calculated for a point 6 feet above the ground
(approximates waist height in a house built on a raised foundation).
Average ground was assumed.
Although the data certainly isn't good to the 4-significant figures
given in this table, it provides a feel for how the near field varies
by distance. Note that the field strength actually increases along
the x-axis (direction of boom) until it reaches a peak and then falls
off. On the other hand, the field strength along the y-axis falls
off continuously from the origin (although there is a "lump" in the
curve).
For this antenna at 45 ft, the maximum field strength occurs at a
distance of 26 feet along the x-axis. However, the maximum occurs
at 54 feet for the antenna at 90 ft. This results in crossing the
3.0 V/m level closer to the tower for the 45 ft height, than the
90 ft height.
Obviously, the "real world" situation is more complicated than this,
since this modeling assumes no buildings, trees, power lines, or any
other nearby objects.
<----------- 45 ft ----------> <----------- 90 ft ---------->
Dist <-- 1500 W --> <-- 100 W --> <-- 1500 W --> <-- 100 W -->
(ft) x-axis y-axis x-axis y-axis x-axis y-axis x-axis y-axis
----------------------------------------------------------------------
0 11.78 11.78 3.04 3.04 4.80 4.80 1.24 1.24
2 12.58 11.75 3.25 3.03 5.06 4.80 1.31 1.24
4 13.35 11.67 3.45 3.01 5.32 4.78 1.37 1.24
6 14.08 11.53 3.64 2.98 5.57 4.76 1.44 1.23
8 14.77 11.36 5.82 4.73
10 15.39 11.15 6.07 4.69
12 15.95 10.94 6.31 4.64
14 16.44 10.74 6.55 4.58
16 16.85 10.58 6.78 4.51
18 17.18 10.47 7.00 4.44
20 17.43 10.41 7.21 4.36
22 17.61 10.38 7.41 4.28
24 17.70 10.35 7.61 4.19
26 17.73 10.30 7.79 4.10
28 17.69 10.22 7.96 4.00
30 17.58 10.10 8.11 3.91
32 17.42 9.95 8.26 3.82
34 17.21 9.76 8.39 3.72
36 16.96 9.54 8.50 3.64
38 16.67 9.30 8.61 3.55
40 16.35 9.05 8.70 3.48
42 16.01 8.78 8.78 3.42
44 15.64 8.51 8.84 3.38
46 15.26 8.23 8.89 3.35
48 14.87 7.95 8.93 3.34
50 14.47 7.67 8.96 3.33
54 8.99
65 3.00
84 3.00
102 3.00
162 3.00
213 3.00
73 de Bruce, WA7BNM (bhorn@netcom.com)
|