Transcript COMMUNICATING OVER LOE FM SATELLITES

COMMUNICATING
OVER LOE FM
SATELLITES
LARRY BROWN
WB5CXC
WB5CXC making a satellite
contact
Equipment
Dual Band Handheld - 2M & 70 CM
Dual Band Antenna - 2M & 70 CM (3
elements on 2M - 6 elements on 70 CM)
Duplexer for the antenna
Satellite Tracking Program
Portable Recorder (optional)
FINDING THE
SATELLITES
THERE ARE SEVERAL PROGRAMS
AVAILABLE
ORBITRON IS A CARDWARE PROGRAM
Orbitron Main Screen
Setting up for a Prediction
Results of a Prediction
What kind of coverage etc. do we have at
4/01 @ 9:30
Azimuth
Elevation
On 4/01/08 at 20:35 at 10 deg. elevation and 177 deg.
azimuth
you will get AOS (Acquisition of Signal).
On 4/01/08 at 20:40 at 63 deg. elevation and 258 deg. azimut
you have Mid-Path (highest elevation).
On 4/01/08 at 20:45 at 10 deg. elevation and 340 deg. azimuth
you will get LOS (Loss of Signal).
Most of the time you need to try for a Mid-Pass elevation above 30 deg. ~
10 deg. elevation is
the practical elevation to start hearing the satellite and ~ 15 deg. is where
you can start
making contacts.
Simulation of a pass in the Future
MacDoppler - MAC program - 3D View
MacDoppler - MAC program - 2D View
Antenna
Dual Band Antenna - 2M & 70 CM (3
elements on 2M - 6 elements on 70 CM)
Homebuilt using a 1” X 2” pine boom ~ 3’
Elements are made from #8 solid copper
wire
Arrow Antenna Duplexer
Antenna Plans
Cheap Antenna designed by WA5VJB
Web site
www.fredspinner.com/W0FMS/cheapyagi/v
jbcy.html
2M Elements are rotated 90 degrees from
70 CM Elements
Arrow Antenna 10W duplexer (board +
parts ~ $ 29)
Elements are #8 bare copper wire (~ 1/8”)
440 Mhz Driven Element
3 Element 2 M Yagi
2M Driven Element
WA5VJB Cheap Antenna Design
2M & 70CM
Arrow Antenna
10W Duplexer
AO-51 Frequencies
Transmit 145.920
Receive 435.300 + 10 Khz doppler effect
Doppler Effect - satellite coming towards
you - the frequency is higher - when the
satellite is going away the frequency is
lower
AOS
Mid-Pass
LOS
Transmit
Tone
Receive
145.920
67.0
435.310
145.920
67.0
435.305
145.920
67.0
435.300
145.920
67.0
435.295
145.920
67.0
435.290
Operating
Set your handheld for receive on 435.310
and transmit 145.920 tone 67.0 hz
Open your squelch (satellite won’t be full
quieting)
Observe the time and point your antenna
toward the bearing and elevation as
indicated by the software
When the noise starts to fade you are
starting to pick up the satellite
Yaesu VX-5
Using both VFOs
1 for Tx the other for Rec’v
Azimuth
Elevation
On 4/01/08 at 20:35 at 10 deg. elevation and 177 deg.
azimuth
you will get AOS (Acquisition of Signal).
On 4/01/08 at 20:40 at 63 deg. elevation and 258 deg.
Azimuth you have Mid-Path (highest elevation).
On 4/01/08 at 20:45 at 10 deg. elevation and 340 deg.
Azimuth you will get LOS (Loss of Signal).
Most of the time you need to try for a Mid-Pass elevation above 30 deg. ~
10 deg. elevation is the practical elevation to start hearing the satellite and ~
15 deg. is where you can start
making contacts.
The satellite will start to fade, rotate your antenna to get a
stronger signal (changing the antenna phase).
As the signal gets muffled or the satellite gets higher you will
have to decrease the frequency due to the doppler effect.
Typical exchanges are short “This is Whiskey Bravo 5 Charlie Xray Charlie Echo Mike 2 0” “Copy EM 2 0 N5FGM EM 45”
The exchange is your call sign and your Grid Square - mine is EM20. Give your
call using ITU phonetics.
Worked Grid Square program:
http://VE2ZAZ.net/WorkedGrids/WorkedGrids.htm
IOio Satellite Antenna
432 IO Satellite Antenna
Egg Beater II - 432Mhz