Hello internet friends!

This week was my eighth at Columbia University’s Plasma Physics Laboratory, and while my time in the lab this summer is drawing to a close next week, the circuit I’m building is tantalizingly close to working. I’m attaching a picture of the circuit and the box that I’ve put it in, so you all can see what the finished product will look like.

IMG_20140725_171643

The week started with my continuing struggle with programming the microcontroller I’ve been using to make a de facto frequency controlled resistor. By doing a lot of googling and reading through online forums, I was finally able to get the microcontroller working on Wednesday afternoon. This was a HUGE breakthrough for me, because I’ve been struggling with this, unsure if it would ever work since about the 5th or 6th week of this fellowship. It was an amazing feeling to turn a knob on my desk that controls the frequency of an incoming signal and see the corresponding drop in resistance that I need for my circuit to function correctly.

The next step was soldering in the new part of the circuit, which is composed of the three new chips into their proper place in the circuit. Once that was done, on Thursday morning, I ran into some issues that made both Thursday and Friday very frustrating for me. I had tested the circuit without the three new chips before I soldered them in and everything worked the way I expected it to, however once I put in the new chips, short circuits came up and I had to struggle to find the places where I had made bad connections. Compounding my frustration was my expectation that now that the hard part was over (the programming of the microcontroller) everything would be smooth sailing. One lesson that I’m definitely taking away from this fellowship is that the little things that aren’t supposed to be difficult are often those that take the longest. I shouldn’t let it get to me, but the circuit is so close to working and I’ve only got a week left before I go back to San Francisco, so I’d really like to get it done before I get on a plane and leave for two weeks.

I was able before the end of Friday to locate the source of the problems and fix them, but by then it was 5:30 and I wanted to go home. I should (should being the operative term) be able to go into the lab on Monday morning, hook up the new box, and test it. However, I will not be surprised if I end up trouble-shooting all day. My plan for Monday is essentially to go in and check all the connections in the circuit. If everything looks good, then I’ll go from there. Hopefully, I can get the circuit working the way I want it to, then generate some data to show Professor Volpe. This should be a very exciting week, and hopefully by the end of it, I’ll be able to test the circuit on the CTX (Collisionless Terrella Experiment). Which is one of the big machines in the laboratory.

That’s all for now,

Happy Saturday!

Lucas

Advertisements