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By Lionel H. Edwards, VE7BQH

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1 By Lionel H. Edwards, VE7BQH
EME made Easy By Lionel H. Edwards, VE7BQH

2 W5UN Mt. Pleasant,TX

3 KB8RQ Brookville, OH

4 WB5LBT Baton Rouge, LA (SK)

5 VE7BQH 384 El Collinear

6 DF1VH 4 X DK7ZB 7 el

7 YU7EF 11 Design

8 144 MHz EME Logistics Path loss: Perigee 356,400 km = 251.5 dB
Apogee 406,700 km = dB The Moon is 1 degree wide The Moon has about 7% Reflectability There is Spatial Polarity between two Stations Faraday Rotation

9 EME made easy What has made EME possible today with relatively modest antennas and power?

10 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

11 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.

12 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.

13 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.

14 Choosing an Antenna OF YAGI ANTENNAS ON 2 METERS 144.1 MHz
G/T SIMULATIONS OF A 4 BAY ARRAY OF YAGI ANTENNAS ON 2 METERS 144.1 MHz TYPE OF L GAIN E H Ga Tlos Ta F/R Z VSWR G/T ANTENNA (WL) (dBd) (M) (M) (dBd) (K) (K) (dB) (ohms) Bandwidth +G0kSC 6LFA : +G0KSC 7LFA : G4CQM : DK7ZB : G0KSC 8LFA : K1FO : YU7EF : G4CQM : BQH8B : +G0KSC 8OWL : I0JXX : DK7ZB : +G0KSC 9OWA : +RA3AQ 9S : M² 9SSB : G0KSC 9LFA :

15 Choosing an Antenna TYPE OF L GAIN E H Ga Tlos Ta F/R Z VSWR G/T
ANTENNA (WL) (dBd) (M) (M) (dBd) (K) (K) (dB) (ohms) Bandwidth DK7ZB : +YU7EF 10LT : K5GW : +G0KSC 10LFA : G4CQM : K1FO : YU7EF : +G0KSC 10OWL : I0JXX : BQH 12J : M : WB9UWA : DK7ZB : +YU7EF 11B : K1FO : G0KSC 11LFA : *M2 20 XPOL :

16 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

17 Commercial Preamps Advance RadioResearch (ARR) Down East Microwave
SSB Electronics Stand alone preamps or preamps with switching are available. An alternate choice is building your own.

18 The Transceiver ICOM IC-746 Yaseu FT-847 Kenwood TS 2000 TX Power
150 – 200 watts

19 EME Station Layout #1

20 EME Station Layout #2

21 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!

22 Lionel H. Edwards, VE7BQH MS Word Document: CTRL + Click to follow link WSJT Software: VE7BQH G/T Tables: or or Antenna Designers/Manufacturers: The 17B2 antenna only

23 Lionel H. Edwards, VE7BQH MS Word Document: CTRL + Click to follow link EME Chat Link: EME Reflector (Moon-Net): Calculate Radio Noise Figure: Calculate Overall System Noise Figure: Preamps:

24 Help is Available If you have questions or want help with antennas, preamps or what ever. I am available by Lionel,

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