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Working on a 38 GHz TWT amplifier to test and modify to 47 GHz, not sure if it will work out I found a Hughes 8000 TWT amplifier for 38 GHz able to make 40 Watt output.
The first I needed for testing this was a dummy load and a coupler to be able to measure the power output. AEROWAVE 22-2020S WR22 Square Flange (UG719/U) Medium Power Load, 15 Watts average, 1.1 VSWR
Then I started up the TWT for the first time to see if
operation looks normal, after heating up waited for some time and then switched
to on
At the end of may 2020 I received my new pre-amp LNA to be placed in front of my transverter
Mny Tnx to all who made this LNA possible, it will be a very important improvement of my RX system I will need to make some mechanical changes in my RX system to place the LNA in my RX chain On 7 april I mounted the encoders for antenna readout and I measured moonnoise
Later that day I did moon noise measurements
My first moon noise measurement was at 17 degrees elevation 0,45 dB The best measurements I did was at 25 degrees elevation with 0,58 dB, see picture above
During the testing of my gearbox I already found that it was turning much too fast for reliable tracking. I searched for possible solutions and decided to try if a pulse width modulated power supply for the electromotor would help I found these small PWM motor controllers and decided to try if this would give me the solution
On 12 march I received this unit and first indication during a test looked promising. As soon as weather permits I want to test this on the gearbox and hope that it will work out as hoped for. At 3 march 2020 I made my first solar noise measurement using the 1.8 mtr dish and my home made feed I had, as can be expected. to optimize the position of the feed for best performance My first solar noise measurement resulted in a bit more than 2
dB.
This is already a nice result after only 20 minutes of trying. I also measured hot earth cold sky resulting in about 0.8 dB
In December 2019 I started with a first setup for 47 GHz EME Hearing from several stations working to be QRV with low power I joined in and see what would be possible My first trial will be to test RX on 47 GHz and see if my antenna would be useable I had a gearbox available for this but it needed an other
electro motor because the original motor was turning After removing the motor I build a replacement able to mechanical fit at to place of the old one
After the modification of the gearbox the antenna was still
turning much too fast. I also had to make a feed holder. I started with the original
11 GHz feed which was a feedhorn for 11 GHz with a round feed and several
chokes.
To understand the possibilities to make a 2 way QSO using WSJT or CW I tried to make calculations based on station parameters which are possible by now My first calculation trial is based on 1Watt output and a
noise figure of 5 dB I found a nice presentation from UA3AVR Take a look at 47 GHz EME performance data from several stations
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