Transcript "EME made Easy" presentation

EME made Easy
By Lionel H. Edwards, VE7BQH
W5UN Mt. Pleasant,TX
KB8RQ Brookville, OH
WB5LBT Baton Rouge, LA (SK)
VE7BQH 384 El Collinear
DF1VH 4 X DK7ZB 7 el
YU7EF 11 Design
144 MHz EME Logistics
• Path loss:
Perigee 356,400 km = 251.5 dB
Apogee 406,700 km = 253.5 dB
• The Moon is 1 degree wide
• The Moon has about 7% Reflectability
• There is Spatial Polarity between two
Stations
• Faraday Rotation
EME made easy
• What has made EME possible today with
relatively modest antennas and power?
WSJT
• WSJT Software was developed by Joe
Taylor, K1JT
• Meteor Scatter, Ionospheric and EME
• What does WSJT do for you?
• 6 dB improvement over what the ear can
hear
What do we need to work EME
using WSJT?
• A minimum of 15 dB of REAL antenna gain
• A mast mounted preamp
• 200 watts of TX Power
• It can and is done with less but you may
be depending on the station at the other
end to make up any gain difference.
What Band to Choose?
• The best choice to start is 2 Meters
• Why? It is far the most active band. As a
consequence it is easy to find a schedule
partner.
• Technology more manageable than higher
frequency bands.
The Antenna
• It all starts with the Antenna
• Use the VE7BQH 144 Mhz Chart to
choose or evaluate
• Especially watch for VSWR Bandwidth,
Front/Rear and the overall G/T
• What is G/T? G/T is a overall figure of
merit. In simple words, the forward gain
divided by the sum of all the side and rear
lobes.
Choosing an Antenna
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G/T SIMULATIONS OF A 4 BAY ARRAY
OF YAGI ANTENNAS ON 2 METERS
144.1 MHz
TYPE OF
L
GAIN
ANTENNA
(WL) (dBd)
•
+G0kSC 6LFA 1.13 9.71
+G0KSC 7LFA 1.39 10.62
G4CQM 7
1.50 10.76
DK7ZB 7
1.57 11.11
G0KSC 8LFA 1.79 11.06
K1FO 10
1.84 11.34
YU7EF 8
1.87 11.31
G4CQM 8
1.90 11.61
BQH8B
1.88 11.60
+G0KSC 8OWL 1.95 11.63
I0JXX 8
2.04 12.11
DK7ZB 8
2.09 11.98
+G0KSC 9OWA 2.09 11.99
+RA3AQ 9S
2.12 12.04
M² 9SSB
2.12 11.99
G0KSC 9LFA 2.14 11.97
E
(M)
H
(M)
Ga
Tlos Ta
(dBd) (K) (K)
2.60
2.84
2.89
3.16
2.94
3.10
3.04
3.20
3.28
3.13
3.44
3.35
3.33
3.35
3.33
3.26
2.19
2.49
2.53
2.84
2.60
2.78
2.71
2.88
2.97
2.82
3.15
3.06
3.04
3.06
3.03
2.94
15.66
16.53
16.69
17.13
17.01
17.27
17.23
17.56
17.62
17.55
18.09
17.96
17.96
18.02
17.95
17.88
3.20
1.80
7.90
5.80
3.60
4.30
3.80
9.30
7.20
4.60
8.20
4.70
4.90
4.70
8.10
5.20
F/R
Z
VSWR
G/T
(dB) (ohms) Bandwidth
236.40 24.5
248.90 20.4
239.90 23.5
272.60 16.9
231.90 24.8
257.70 16.5
242.12 20.0
242.60 24.1
259.30 18.0
235.70 25.5
254.50 20.4
251.91 27.8
247.00 21.3
246.50 22.1
244.00 20.7
235.10 23.5
49.3
48.0
50.7
28.4
50.0
29.4
48.5
50.9
50.0
12.5
26.5
16.9
49.1
47.1
15.0
50.5
1.04:1
1.19:1
2.31:1
1.64:1
1.24:1
1.44:1
1.21:1
2.52:1
1.29:1
1.26:1
3.00:1
1.27:1
1.30:1
1.08:1
1.32:1
1.08:1
-5.93
-5.28
-4.96
-5.07
-4.49
-4.69
-4.46
-4.14
-4.37
-4.02
-3.82
-3.90
-3.82
-3.75
-3.71
-3.68
Choosing an Antenna
TYPE OF
ANTENNA
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DK7ZB 9
+YU7EF 10LT
K5GW 10
+G0KSC 10LFA
G4CQM 9
K1FO 12
YU7EF 10
+G0KSC 10OWL
I0JXX 12
BQH 12J
M2 12
WB9UWA 12
DK7ZB 10
+YU7EF 11B
K1FO 13
G0KSC 11LFA
*M2 20 XPOL
L
GAIN
(WL) (dBd)
2.39
2.49
2.49
2.49
2.52
2.53
2.59
2.63
2.68
2.80
2.84
2.87
2.87
2.87
2.89
2.95
2.97
12.41
11.84
12.45
12.45
12.63
12.49
12.44
12.46
12.67
12.80
12.68
12.73
13.00
12.92
12.94
13.11
13.07
E
(M)
H
(M)
Ga
Tlos Ta
(dBd) (K) (K)
3.56
3.13
3.44
3.39
3.62
3.46
3.39
3.40
3.58
3.67
3.48
3.48
3.87
3.58
3.64
3.66
3.65
3.30
2.82
3.16
3.09
3.35
3.18
3.10
3.10
3.30
3.40
3.20
3.20
3.60
3.30
3.39
3.37
3.65
18.45
17.69
18.38
18.35
18.68
18.42
18.34
18.36
18.64
18.83
18.54
18.61
19.17
18.85
18.88
19.02
19.05
6.20
5.30
7.40
4.10
7.30
4.30
6.90
7.20
6.90
4.30
5.40
7.00
6.80
4.70
4.60
5.50
7.40
F/R
Z
VSWR G/T
(dB) (ohms) Bandwidth
250.50
224.30
234.60
226.70
244.40
240.70
227.80
224.60
238.00
246.20
232.50
223.00
247.50
225.60
239.20
223.60
241.70
20.4
29.4
23.1
23.8
22.2
21.6
23.8
26.4
25.2
20.3
19.5
25.2
21.7
25.6
19.7
25.4
21.9
27.5
45.7
37.4
47.4
46.4
31.1
50.3
12.3
26.9
50.0
37.0
23.9
25.8
50.2
24.7
48.4
21.0
1.23:1
1.13:1
1.41:1
1.24:1
2.02:1
1.23:1
1.06:1
1.11:1
1.31:1
1.01:1
1.13:1
1.47:1
1.61:1
1.35:1
1.38:1
1.03:1
1.28:1
-3.39
-3.67
-3.17
-3.06
-3.05
-3.25
-3.08
-3.00
-2.97
-2.93
-2.97
2.72
-2.62
-2.53
-2.76
-2.33
-2.63
Choosing a Preamp
• The very best Noise Figure of any of the
Japanese VHF capableTranceivers like
the ICOM IC-746, Yaseu FT-747 or
Kenwood TS 2000 is 4 dB
• You need to strive for a composite Noise
Figure of under 1 dB.
• Therefore, the preamp should have a
Noise Figure of about 0.5 dB
Commercial Preamps
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Advance RadioResearch (ARR)
Down East Microwave
SSB Electronics
Stand alone preamps or preamps with
switching are available.
• An alternate choice is building your own.
The Transceiver
• ICOM IC-746
• Yaseu FT-847
• Kenwood TS 2000
• TX Power
• 150 – 200 watts
EME Station Layout #1
EME Station Layout #2
Summary
• It starts with a well designed antenna
• Then comes a good mast mounted
preamp.
• The old adage that if you cannot hear
them you cannot work them is alive and
well on EME!
Lionel H. Edwards, VE7BQH Email: [email protected]
MS Word Document: CTRL + Click to follow link
• WSJT Software:
• http://www.physics.princeton.edu/pulsar/K1JT/
• VE7BQH G/T Tables:
• http://www.g0ksc.co.uk/component/content/article/25-theproject/139-ve7bqh-gt-table.html
• or http://www.yu7ef.com/
• or http://www.sm2cew.com/gt.htm
• Antenna Designers/Manufacturers:
• http://www.g0ksc.co.uk/
• http://www.yu7ef.com/
• http://www.qsl.net/dk7zb/start1.htm
• http://myweb.tiscali.co.uk/g4cqm/
• http://www.m2inc.com/index2.html
• http://www.m2inc.com/PDF%20Man/pdfman.html
• http://www.cushcraftamateur.com/ The 17B2 antenna only
Lionel H. Edwards, VE7BQH Email: [email protected]
MS Word Document: CTRL + Click to follow link
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EME Chat Link:
http://www.chris.org/cgi-bin/jt65emeA
EME Reflector (Moon-Net):
http://list-serv.davidv.net/mailman/listinfo/moon-net_listserv.davidv.net
Calculate Radio Noise Figure:
http://vk1od.net/calc/RxSensitivityCalc.htm
Calculate Overall System Noise Figure:
http://www1.sphere.ne.jp/i-lab/ilab/tool/NF_e.htm
Preamps:
http://www.advancedreceiver.com/
http://www.downeastmicrowave.com/
http://www.ssbusa.com/
Help is Available
• If you have questions or want help with
antennas, preamps or what ever. I am
available by Email:
Lionel, [email protected]