So, admittedly, this is a little bit of an intimidating project. There are a lot of elements to what goes into generating RF energy, and I guess I'm pretty lucky that I've simplified a lot of it by by purchasing the Icom 905. I don't have to worry about a transmitter, and then a transverter. Everything's all in one, and I also have the RF unit of the 905 able to be mounted remotely, or really close to the antenna feed point.
With that out of the way, there is still some complication to what I consider two paths for RF to flow. We've got the receive side, and the transmit side. Affectionately known as RX and TX.
Just brainstorming what I have, I felt like the easiest path to test will be the RX side of things.
If you think about it working backwards from the antenna (or I should say the septum feed point - oooohhh that sounded really cool to say) you have a connection to the low noise amplifier (LNA) then a connection back to the radio. So if I just want to test the receive side, I think I should be able to set up my antenna/dish, and hook up the LNA, and 905 and should be able to make sure everything works by trying to receive some of these signals that are being bounced off to the Moon by some of my soon-to-be friends all around the world. (Yes I'm talking to you guys on the groups.io and Facebook sites!)
The first thing I felt I needed to do is create a mount for the LNA pre-amp to attach to the Septum feed. I also needed a relay up there to ground the line when the TX line was active. These LNAs are super sensitive and blasting 250W into them is a sure way to generate magic smoke.
Here is my first prototype that I came up with:
All thats left to do is connect power and the IC-905 to the LNA and I should be in business.
Looks like everything might be working - When I turn on the LNA, the noise floor comes up considerably. Looks like it might be time for some rotator fun since that would be important to make sure I am actually pointing at the moon!
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