This day had been a long time coming, and despite a few hiccups, it went surprisingly well. I opened SDR# to analyze the signals from my radio dish, but first had to calibrate the telescope so real signals wouldn't be drowned out by noise. To do that, I had to plug in the end of my telescope's cable and point the dish straight down—away from the Milky Way and any other sky sources—and run the “Acquiring Background” routine. This process measured the telescope's own noise signature and automatically subtracts it from every subsequent signal I record.
Once it had corrected for background noise, I paused the software and unplugged my dish from the extension cable. I needed to be outside with the dish to point it straight up at the sky. The problem was that my computer is on the second floor. To solve this, I plugged one end of my 16-foot extension cable into my computer and fed the other end out the window.
Believe it or not, this actually worked. I picked up my dish (with the low-noise amplifier and RTL-SDR) and went downstairs to my backyard, where the cable was hanging. I plugged the end of the extension cable into the RTL-SDR, laid the dish on a chair outside, and ran back upstairs to resume the software. I also made sure a camera was recording my monitor so I could catch any spikes in the signal. Then I started recording and ran back downstairs:
There were two problems during this initial test run. First, the Milky Way wasn't visible the day I tested the telescope. It was just on the horizon, and a wall in my backyard blocked any possible signal. Knowing this, I pointed the dish straight up into the sky, hoping to pick up the hydrogen line from some planet or distant galaxy. Were my hopes high? No, but I was leaving for a trip in a few days, and I didn't want to wait weeks to test my prototype. Second, my monitor turned off while I was picking up signals, so I missed two-thirds of the data. It's not all bad, though, because I still managed to get some results.
So how were the results? They seemed pretty good. Now, I'm no expert—I'm just some kid who did research on the internet—but I noticed some peaks pop up in the software. Was this the hydrogen line? Maybe, but at least these results show that my telescope can pick up signals from space. The next step is a big one: I want to create my own software similar to SDR#. Once I do this, I can modify it to run on a Raspberry Pi (a small computer that can be programmed to do anything) and then install the Pi into my radio telescope so it can run independently. This will take some time, though, and I'll update you all along the way. Stay curious.