https://mars.nasa.gov/odyssey/
1.2m dish, 1dB NF LNA, modified Ku feed. 0.7Hz bandwidth using an Airspy R2 with HDSDR, 9GHz LO.
8406.468MHz
https://mars.nasa.gov/odyssey/
1.2m dish, 1dB NF LNA, modified Ku feed. 0.7Hz bandwidth using an Airspy R2 with HDSDR, 9GHz LO.
8406.468MHz
Nice signal last night. 8406.852MHz
-118dBm, 142kBd on DSS55, Madrid
62.3Mkm
Comparing the 2 plots, you can see the effect of the bandwidth being too narrow when the Doppler change is fast.
Thanks satesco. The system I'm using at the moment is:
A home made conical feed, squashed tube circular polariser, transition to co-ax, home made LNA, Miteq LNA, all outside. That comes in, at 8.4GHz, via low loss cable to another Miteq amplifier and then a spectrum analyser as the receiver. The 21.4MHz output from the analyser goes to an AIrspy HF+ and a PC running HDSDR or sometimes SDR#. I sometimes use my original rat's nest down converter in place of the spectrum analyser. That has an IF around 500MHz fed to an AIrspy R2. Everything is locked to a GPS locked frequency reference. The electronics itself has an NF about 1.2dB for the whole system but the overall system noise figure, including feed, dish and ground noise, is about 2.5dB. I get around 8dB Sun noise. There's plenty of room for improvement!
When I get some time I'll post a 'HowTo'.
Not showing on DSN Now but a good signal.
RX tuned to 8406.707MHz
66.5Mkm
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