EHG on 24 ghz eme

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Worked OK1KIR on 9 june 2011, after several partials in 2008, caused by failures in equipment, we were able to make our first QSO in 2011

Spectran display from the signal from OK1KIR

Stations worked:
6 april 2008 LX1DB   #1 and first ever PA and LX  Signal recording from LX1DB
6 april 2008 DF1OI   #2  Signal recording from DF1OI
6 april 2008 DK7LJ   #3  Signal recording from DK7LJ
6 april 2008 VE4MA  #4 and first ever PA and VE  Signal recording from VE4MA
9 april 2008 W5LUA #5 and first ever PA and W5  Signal recording from W5LUA
9 june 2011 OK1KIR #6 and first ever PA to OK  Signal recording from OK1KIR

 

 

  

 

On 9 april I had a sked with W5LUA
I made a QSO with W5LUA, he was very strong with me but I learned that my understanding of doppler was not correct. I must do some study to better understand the doppler. My misunderstanding was no problem because Al was very strong and even when I was searching 30 khz below the right frequency I easily found his signal.
Listen to the signal from W5LUA during our QSO.
Its hard to imagine that this is the same station as the audio I first heard on 9 march from Al.
Two major changes since that first time I heard Al:
    - my dish was not optimal so I lost 2.3 dB,
    - it was raining at the first time and sunny during our QSO

This is the spectran diagram from W5LUA during our QSO

On 6 april I made my first QSO's
After the redesign of the transmitter and a change to the doubler I was ready to make a new test. I made a sked with LX1DB who had a very strong signal. In total I made 4 QSO's today. OK1KIR also copied my signals but unfortunately he was having problems with his system. We will try again later.

 

The 12 GHz brick and multiplier than an attenuator and a 0.5 Watt amplifier The TX system in the dish The Hughes TWT via a short flex to the waveguide switch
 
Grotere kaart weergeven
After the 4 QSO´s tired but happy.  You can even see my dish on Google earth, the white spot in the middle with the shadow on the ground
Spectran diagram of LX1DB

On 4 april I did my first test for a QSO with OK1KIR
After I build up my TX system into the dish I did my first test and found that the TX was not working. After a short time I found the doubler from 12 to 24 GHz broken, I changed this for a new one and the TX worked for one transmission and then again no output. Something was wrong in my setup so test for today were stopped.

On 3 april I could measure moonnoise for the first time after the focus allignment
I started today to measure the moonnoise. After several measurements the maximum value I measured was 2.4 dB with clouded sky. So my dish performance looks OK.
I also completed the build-up for my transmitter and made everything ready for my first test.

Waveguide switch with flex to transmitter and pre-amp mounted in the antenna

 

transmittter is a brick followed by a doubler then a
attenuator and then a 0.5 W amplifier
TWT in test setup

 

On 29 March I made a big improvement to my dish
I tried today if my dish feed was correct in the focus because the measured solar noise and moon noise was a little bit low compared to others. This was a day with good weather but much wind. When I started I measured 12.9 dB solar noise. I shifted the focus about 2 mm closer to the dish and I measured 13.5 dB. I total I shifted the feed 4 times and at the end I measured 15.2 dB solar noise. This is an improvement of 2.3 dB which is a lot.

I have been working the last week to get my transmitter up and running and at this moment I have a setup of a 12 GHz brick followed by a doubler, than a 0.5 Watt solid state amplifier and than the Hughes TWT which I used several years ago with my first experiments to get power. With the improved drive I now measure about 12 Watt output. I want to try next week to be QRV for my first EME test.


This is the 24 GHz feed in front of my dish

On 9 march 2008 I copied my first EME signals on 24 GHz.
I copied signals from OK1KIR, W5LUA, VE4MA and LX1DB. Signals were very weak and very noisy due to spreading.
This might be caused by the rain which was falling.
During the test the weather was not good, we had about 1 to 3 mm per hour rain all the day.

In the Spectran waterfall you can see the signal from OK1KIR. In the second waterfall you can see me tuning over the signal from VE4MA.

The signal from W5LUA the strongest signal I heard during this weekend.

You can listen to the signal from W5LUA; the signal is very weak. transmitting RO RO several times then after a short break VE4MA de W5LUA