Hams in Space!

73 Review by Dick Goodman WA3USG
Number lOon your Feedback card
Skymoon
Software for EME communications.
Skymoon
9102 Kings Drive
Manvel TX 77578
(713)331-4200
Price Class: Version 1, $40; Revision 2, $50
One evening in tate November
1990, I received a telephone
call from Bill Brown WBBELK informing
me that Dave Blaschke
WSUN was on the air operating
rnoonbounce. Bill suggested that I
try receiving WSUN on 2 meters. I
was quite pessimistic about my
chances because my antenna system
consists 01 a single Hy-Gain circularly-polarized
yagi used for
OSCAR satellite operations. I do,
however, have a low-noise mastmounted
preamp and a short (60
foot) run of RG-213 coax going to
the shack, so I gave it a try.
It took about 10 minutes , but from
under all the noise I was finally able
(barely) to make out the W5UN's
callsign on CWo It was about the
weakest signal that I have ever
heard, but considering that I was
using a single yagi it was quite an
accomplishment. I have read articles
in several amateur journals
stating that the big guns on moonbounce
could be received on modest
equipment, but I never believed
it, until now!
While the "Instant Track" program
gave me the azimuth and elevation
of the moon, and allowed me
to automatically point my antenna, I
found there were quite a lew other
considerations not addressed by
this software package for moonbounce
operations.
Enter: Skymoon
Computer software has certainly
evolved in the last 10 years, especially
in the field of amateur radio.
Since the software developers who
write ham radio applications sottware
are usually hams themselves, they are
generally technically-oriented individuals.
This translates into a useful software package
for others with similar interests. look at the
impact of " Packet Cluster," and the variations
of logging programs on chasing DX . There are
also many effective propagation forecasting
programs for determining when OX will be
available. For the ham interested in OSCAR
operations, there are seve-at good satellite
tracktnq programs which will indicate when
the desired satellite will be in view, Now, lor
40 73 Amateur Radio Today - March,1991
Photo A. Main screen ofSKYMOON.
Photo 8. Map showing the moon's location in relation
sources in the sky, as viewed from yourOTH.
the ham interested in moonbounce, or EME
(Earth-Moon-Earth) communications, there is
a spiffy new software package called "Skymoon,"
written by Dave Blaschke WSUN, of
international moonbounce fame!
I reviewed Skymoon on two different cornputers:
a Beuren AT clone running at 12 MHz
with a VGA display, and a Comp-U-Add 386
running al16 MHz using an EGA, and later a
VGA, display,
There are two revisions of Skymoon. Revision
1.0 will run on any IBM PC clone with
Hercules, CGA (Mode 4), or a CGA
monitor. Version 1.0 comes on a
single 5.2S" floppy disk, and it can
be executed and run from a single
drive system. Revision 2.0 comes
on two 5.25" floppy disks, and requires
either a hard drive or a larger
capacity floppy drive (720K, 1.2M,
or 1.44M). Skymoon requires 2S6K
of memory to run. For this article, I
primarily reviewed Revision 2.0, but
I'll provide a brief comparison to
Version 1.0 later in the review.
Skymoon is easy to install-you
simply copy all the files from the two
floppy disks to their own directory
on your hard drive. Before you run
Skymoon, you must execute a configuration
program. This tells Skymoon
your offset to UTC, call, QTH,
and latitude and longitude.
To start Skymoon, type "SKY­
MOON" and press < ENTER> . It
takes Skymoon about 10 seconds
to draw its graphical interface
..
ami screen. This generates a world map
..
showing the location of the moon
and a moon rise/sel line (see Photo
A). rotne right of the map isa menu
which describes the purpose of
each function key. Below the map
are multiple windows of real-time
data containing the following information:
-The primary station (your station)
azimuth and elevation to the
moon (if the moon is not in view, the
elevation will be a negative number).
eThe current distance to the
moon in kilometers .
to noise »The background sky temperature
in degrees Kelvin. Depending
on where the moon is in relation to
noise sources in the sky, this value will
change.
-Path loss in dB relative towhen the moon is
closest.
-rcterpath degradation in dB.
s The moon declination angle and the
Greenwich hour angle (GHA).
-For those used to astronomical positioning
parameters, the moon right ascension and the
semi-diameter.
Next to each parameter is an arrow that
gives the status of each (increasing or de-