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My new setup for receiving DL0SHF on 10 GHz EME
I have build myself a receive system for DL0SHF. In november 2014 I started with a new setup using a PLL LNB and a 60 cm offset dish, more info will follow as I am proceeding. My Receive system is based on a 48 cm Procom dish, a DB6NT pre-amp with 0.7 dB nF and a DB6NT transverter. This is mounted on a small gearbox Az-El which is for sale as a gearbox for telescope mount for astronomy Today 30-3-2014 I received DL0SHF beacon with my new setup. It was performing better than my previous setup with a 50 cm dish being my portable station and not as well defined for EME. Listen to the signal received from DL0SHF in CW listen to the JT signal from DL0SHF Download the SDR recording for Spectravue Please
keep in mind that the different Spectravue pictures from signals have been made
on different days CW signal in Spectravue 14dB S/N in 12 Hz bandwidth plot scale is 2 dB/div
The JT signal from DL0SHF Plot scale is 2 dB/div
The decodes from the WSJT signal from DL0SHF (Using WSJT7)
On 1-4-2014 I did a test in receiving DL0SHF on low power I think I found the signal but just a bit too weak to decode I did not understand because in my opinion I missed about 6 dB After contact with the first operator from DL0SHF he confirmed that beacon power had significantly reduced from 50 to 8 W
On 3-8-2014 I received DL0SHF on low power (after repair of the 50Watt PA) Signals were weak but could be found in Spectravue CW signal was audible but much too weak to copy CW signal, the two FSK signals are visible, S/N about 2dB@12Hz resolution bandwidth
JT signal the 4 tones are visible in the waterfall
The JT signal was good to decode (using WSJT9)
Other Signals I did also a test with Charlie G3WDG to try copy his signal with my small dish Station from Charlie G3WDG consists of a 3 mtr Andrew dish and 50 W output
I found his signal instantly in my SDR About 3 to 4 dB S/N ratio in 12 Hz bandwidth This is the first signal I received from G3WDG The plot scale is 1 dB /div
We tried a test if it was possible to take the CW but this was too difficult, the CW tone was audible but just too weak to be able to copy the CW Then we tried WSJT with good decodes
During the DUBUS 3 cm EME contest I found signals from more stations OK1KIR and SP1JLW
Take a look at my system. I use a small gearbox from IOPTRON designed for small
astronomical telescopes. Just calibrate and then aim to the sun or the moon and it's tracking, you cannot get it more easily similar drive available via Robtics
Ready for RX Click on the picture to see a small movie of the dish turning
This is my receive system
I use the funcube dongle in combination with Spectravue After building my receive system I did some testsing to be sure my setup was working I measure 3,3 dB solar noise with this setup Plot scale 0.5 dB/div
Looking at the results from the VK3UM calculator I should be able to get 0.1 dB moon noise With Spectravue in continuum mode I tried to measure this moon noise Plot scale 0.1 dB/div
Life demo during EME 2014 conference receiving DL0SHF high power
Audience was much bigger than expected, sorry for little time to explain to
individuals
The second demo for receiving DL0SHF on low power was cancelled due to the rain.
My presentation during EME 2014 conference Look at Youtube for my presentation during EME 2014:
https://www.youtube.com/watch?v=rsxkfHfrN7k&feature=youtu.be Report from OK1TEH from the EME 2014 conference
These are the calculations of the VK3UM calculator.
In the calculation for DL0SHF I degraded the antenna performance to limit gain
to 52 dB
The important value's are marked with a red circle, Calculation for the high power transmissions from DL0SHF
I should be able to get 17,3 dB S/N in 12 Hz bandwidth
Calculations for G3WDG
I should be able to get 3,2 dB S/N in 12 Hz bandwidth
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