1. Gunter Neugebauer VE7CLD
THE MOON ABOVE 10 GHz
experiences from GHz
Gunter Neugebauer VE7CLD

2. WHY EME?
Challenge
Thrill
Location: poor for VHF
Personal Contacts

3. WHAT BAND? EME is a challenge on every band
Consider 1296 MHz for ++QSO’s
10 GHz:
About 50 stations have done it
Some active
Above 10 GHz:
Few stations
More technical challenge
Everything very hard to get

4. 10 GHz PROBLEMS Frequency stability Frequency spreading (~100 Hz)
Doppler (up to 20 kHz)
Path loss ~ 290 dB
Dish quality
Dish mount (stability & tracking)

5. 10 GHz SOLUTIONS 10 ft dish 20 W Tx power on feed Receiver ~ 1 dB NF
test components before assembly
someone who helps!

8. 10 GHz STATION 12 ft dish 20 W Tx power (TWT)
0.8 dB pre-amp (modified DB6NT transverter)
Sun noise 14+ dB
Moon noise 1.5 dB
Sky to ground < 4 dB

11. bitten by the bug!
on to 24 GHz

12. 24 GHz PROBLEMS – like 10 GHz but more! 10 GHz 24 GHz
Frequency instability
2.5 X
Frequency spreading
~ 100 Hz
200+ Hz
Doppler
up to 20 kHz
~ 60 kHz
Path loss
289 dB
297 dB
Water vapour
minimal
significant

13. 24 GHz MOON TRACKING PROBLEMS
Antenna beamwidth
0.5 deg
0.2 deg
NOTES:
Moon moves 15 degrees per hour
Arc subtended by the moon = 0.5 degree

14. 24 GHz
Started with receive only: home-built pre-amp with DB6NT pc board kit

15. 24 GHz
Later a TWT A plus power supply became available

16. 24 GHz MY STATION 4.5 m (15 ft) dish 100 W Tx power (TWT)
theoretical dish gain 57 dB
100 W Tx power (TWT)
2.0 dB pre-amp (DB6NT kit)
Sun noise 13 dB
Moon noise 1.5 dB
40+ MW ERP

17. 24 GHz BLOCK DIAGRAM LINE AMP TO IF Rx DB6NT Pre-Amp Kit BRICK OSC
-20 V
BRICK
OSC
ATT
TWT A
1297 MHz X2 LO IF
ISO
WR28
adapter HV
13000 V
TO IF Rx
GHz
60 mW
DB6NT
Pre-Amp
Kit
WR28 to
WR42
SEQUENCER
NCCA

21. Oh, oh – smoke!

22. Onward and upward: 47 GHz

23. 47 GHz PROBLEMS MULTIPLIED 10 GHz 24 GHz 47 GHz Frequency instability
2.5 x
5 x
Phase noise
Frequency spreading
~ 100 Hz
200+ Hz
Few hundred Hz
Doppler
up to 20 kHz
~ 60 kHz
120 kHz
Path loss
289 dB
297 dB
~ 303 dB
Oxygen -
0.02 dB/km
0.4 dB/km
Water vapour
0.3 dB/km
0.15 dB/km

24. 47 GHz ANTENNA CONSIDERATIONS
Antenna beamwidth
0.5 deg
0.2 deg
0.1 deg
Tracking
1 min
0.5-1 min
Constant
(automate)
Dish quality
(wavelength)
(3 cm)
(12 mm)
Critical
(6 mm)
Moon angle -
A smaller accurate offset dish is better.

25. 47 GHz MY STATION 4.5 m (15 ft) dish 4.7 dB NF pre-amp (DB6NT)
dish is not made for this frequency
4.7 dB NF pre-amp (DB6NT)
Frequency drift ± few kHZ
Sun noise dB
Moon noise 0.25 – 0.4 dB

27. FIRST EVER 47 GHz MOON ECHOES HAVE BEEN HEARD BY SERGEI RW3BP July 24, RW3BP ECHOES HEARD BY AD6FP, W5LUA, VE4MA and VE7CLD August 2004

28. RW3BP TEST SIGNAL

30. 47 GHz ORIGINAL RECEIVER 12.24 GHz 9.071 ATT 1st BRICK OSC
2nd BRICK OSC
DB6NT
4.5 dB WG
acts as
FILTER x3 LO
2nd IF
1297
To shack
75 Ω
Philips
CONVERTER
MODIFIED SAT LNB
GHz
1st IF RF IF
6” BRASS
WR15

31. 47 GHz IMPROVED RECEIVER 11.4470 GHz XTAL 105.997685 MHz PLL WA6CGR
VCO VOLT
DB6NT
PRE-AMP
4.5 dB
W2PED or
OE6PMI
FILTER IF
to shack
U+18V
SAT LINE AMPS
10 MHz
from
GPS x4 LO
DC BLOCK
FXTAL

32. 47 GHz IMPROVEMENTS in progress
Improved feed system (0.4 dB moon noise)
Frequency locked to GPS
Auto Doppler correction
Auto tracking (to middle of moon)
CW averaging software

33. FIRST EVER CW QSO’s completed by RW3BP and AD6FP, W5LUA, and VE4MA
47 GHz
signal
RW3BP
(averaged)
at W5LUA
VE4MA
(averaged)
at AD6FP

34. RW3BP feed and dish
2.4 m dish
100 W output
50 MW ERP
1 dB moon noise

35. 2.4m Dish at VE4MA

36. 2.4 Meter Dish at W5LUA

37. AD6FP 47 GHz 1.8 Meter Dish
1.8 m dish
30 W output
1 dB moon noise

38. Liquid Nitrogen Cooling for Better NF AD6FP
1.5 dB 77 deg K (4 290 K)

39. Sergei’s TWT could not withstand the stress and died

40. FUTURE PROSPECTS??
Transmit on 47 GHz?
76 GHz Rx?
76 GHz EME?

41. SOFTWARE LINK: www.ve1alq.com
ACKNOWLEDGEMENTS
VE4MA for slides, soundfiles and info
RW3BP, W5LUA, AD6FP
VA7MM
VE7BPE (now AC7FT) for professional measurements 10 GHz
SOFTWARE LINK:
A Few words from Sergei:
Program was done for 47 GHz EME but I hope it will be useful in other cases. It is most effective for microwave CW signals with wide and noisy carrier and quick and sharp QSB. It is less effective on low bands for signals with slow and deep QSB. On 600 s averaging time base it is possible to detect signals close to -40 dB SNR but if it is -40 dB all 600 s. In real life ears or WSJT can be more effective on peaks of QSB.