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IBT Itty Bitty (Radio) Telescope AKA our Lil' GBT

I started playing around with this one last year, but by the time it was ready to go, my astro class was over. So, this year I started early. It's a simple radio telescope with substantial limits, but just enough "Wows" to make it effective enough to engage the students in a great discussion about radio astronomy.

     It all starts with a satellite dish. You may be surprised how easy these are to come by. I asked if any students had one laying around, and I had 3 the next day. I even had an 8 footer dropped off. But that's for next time.
      You may need to be creative about the mount. My limited imagination came up with a 2x4, a lazy susan, some glue and screws, and a beat lab stool with a little velcro on the top.

     The next expense (less than $20) is a satellite finder. I suggest that you buy the kit, because it comes with a battery holder and the coaxial cables you'll need. It also comes with a compass. You can use it for pointing if you want. I also have a spot for my cell to sit on that has an app with setting circles for showing RA and DEC.
     The satellite finder has needle gauge that indicates signal strength, and an irritating speaker that changes pitch with signal strength. The great thing about the speaker is that you can cut the wires to it, and connect a 3.5mm microphone jack to plug into you PC's MIC port

The scope was pointed toward a door. It was 0C on this day

Once you plug it into your PC, be sure to change the mic input device in the computers settings to 3.5mm in. If you miss this step, the chart tool will pick up the noise in the room, and figuring out why, can be frustrating. Radio Skypipe has a free chart tool that will work well with this setup'

The kit has a battery holder as a power option, but an old laptop charger works well to. You just need to play with the tip to make it work. It works best between 14-19.6 volts. I am toying around with a solar panel/battery power supply as well, and will report back in a future update.

When all is said and done, you have a great little, low cost, device, that your students can build and test. Here is the connected scope counting people coming into the planetarium during an Open House.

 We will be developing lesson plans to go with this soon. Check for updates!

1 comment:

  1. Just ordered a satellite finder today. Going to use this kind of demonstration for middle school kids. I do EPO at one of the schools here.