Thursday, 6/28/12
I shouldn’t have waited until now to write this post. I knew everything would feel different once I was on the plane.
The last few days have been very stressful and somewhat busy, but mostly because I have been sleep-deprived. The stress caused me to get a whole bunch of canker sores in my mouth, which cause a distracting amount of stabbing jaw pain (like a tiny person with a pickaxe is mining at my gums) as well as throbbing headaches. Sleep is incredibly important.
Monday:
The plan for the day was to get back at around noon, run a bunch of errands, test the system with two hops and with the MacBook as a router, and then go home to J. I did get back at around noon and tried to meet with Sindy Tan (from my high school, who is at RSI) to give her my bike for the summer. Unfortunately, I realized that my bike was still at the Tang from when I rode it to testing on Friday morning and then had to carry back the antenna back a kilometer and a half (whine whine whine). So I decided I’d be back on Wednesday to give Sindy the bike- on my honor, at all costs. I have issues about that sort of thing.
Then I got haircut, picked up some medicine for the trip (and my canker sores) from CVS, and set up the two hops using all four Bullets down the hallway outside the office in bldg 36. (Almost didn’t have enough Ethernet cables – had to scrounge from the other lab desks, again.) It worked fine, but was extremely slow: 3.29 mbps download and 0.73 upload, with original speed 58.96 download and 2.72 upload. I guess the halving of the throughput when you increase to 2 hops really makes a difference. One thing I didn’t test was the effect of the length of the Ethernet cable at the relay point on the connection speed. Now that I think about it, that could make a big difference; the data has to travel through every cable at the midpoint, so from BulletàinjectoràinjectoràBullet. I wonder how efficient POE is at transmitting data—the fact that we are also modulating the data over a DC power signal (I think) ideally shouldn’t make any difference. But any fluctuations in the DC power signal could also cause bit errors in the modulated signal.
Power over Ethernet also forces you to use Ethernet cables, which is easy but not very signal-efficient. I wish I knew more about radio equipment so I could engineer a solution.
More on what happened on Monday.
The last errand I’d scheduled for that day was to pick up the screw-on “butt” end of the first broadcasting Bullet from Tang, where I’d accidentally left it after testing on Friday, and to pick up my bike. It was an egregious error, by the way. Without the butt of the Bullet, it might not have been waterproof; we would have somehow created a solution, but it would probably have been makeshift at best, and would have wasted precious time and energy. Always keep track of every part of your equipment, even caps and screws and everything—you don’t want to be caught in the field without them.
It was drizzling when I stepped out of the office, and I was carrying nothing but my cell phone. I started running, although I found out later that I might have gotten wetter because of it. The rain started coming harder and harder; lightning cracked the sky and thunder rolled overhead. I counted the seconds – four miles away (to within an order of magnitude, anyway). I was pretty soaked and out of breath by the time I got to Tang, and the storm was getting closer by the minute. But after tucking phone and Bullet butt into a doubled plastic bag, I headed back out to bring the bike back for Sindy. Biking 1.5 km in a short skirt through stormy, flooding streets was quite the adrenaline rush. I squelched back to the Terrascope room dripping from head to toe. Luckily, I had a towel and change of clothes. I stayed with P that night.
Tuesday:
I was exhausted; I tested the system down the hallway (one hop only) using my MacBook as a router, and it worked fine! No idea what had happened that other time down Vassar St. Then I was supposed to go to Radio Shack to get supplies to repair Ethernet and coax cables with – crimp tools of the correct sizes, heat shrink, spare end connectors (N type, 8p8c). Instead, I crashed in the Terrascope room for 5 hours and that effectively ended the day. When I got up, I panickingly searched the web for the items I needed and ordered some of them with two-day shipping (because for some reason my confused brain thought it was still Monday). Instead of sleeping that night, I emailed out to the MIT radio society (w1mx) and MITERS mailing lists begging for N type end connectors, and watched as long as I could. It would have cost me $180 out of pocket to order the connectors and a crimp tool for them online, and they were only spare parts (for pretty important things nonetheless).
Wednesday:
J and I disassembled the antennas and packed everything away into 4 suitcases – 2 just barely less than oversize. We’d been worried about finding a suitcase for the huge 24 dBi antennas’ parabolic dishes, which were 2 by 3 ft and each came apart into 2 by 1.5 ft pieces, but our widest suitcase just barely fit them diagonally.
The MIT radio society also donated some spare N-type solder connectors (no crimp tool necessary)! Thank you, jhawk and w1mx!
All was well (except for maybe my canker sores). Both J and P brought me strawberry rhubarb pie to celebrate.
Thursday afternoon:
Traveling has been surprisingly light-hearted. We ran last-minute errands like binding the science lab manuals, and J made a trip to Radio Shack to get extra electrical tape and some 8p8c Ethernet cable heads that hadn’t arrived on time. I had pie and lunch with P right before leaving, which was great. J is also a very sunny person; I am lucky to be traveling with her.
Now coming into Amsterdam for a 4-hour layover (hopefully enough time to type this up, and maybe buy a real notebook?).
I shouldn’t have waited until now to write this post. I knew everything would feel different once I was on the plane.
The last few days have been very stressful and somewhat busy, but mostly because I have been sleep-deprived. The stress caused me to get a whole bunch of canker sores in my mouth, which cause a distracting amount of stabbing jaw pain (like a tiny person with a pickaxe is mining at my gums) as well as throbbing headaches. Sleep is incredibly important.
Monday:
The plan for the day was to get back at around noon, run a bunch of errands, test the system with two hops and with the MacBook as a router, and then go home to J. I did get back at around noon and tried to meet with Sindy Tan (from my high school, who is at RSI) to give her my bike for the summer. Unfortunately, I realized that my bike was still at the Tang from when I rode it to testing on Friday morning and then had to carry back the antenna back a kilometer and a half (whine whine whine). So I decided I’d be back on Wednesday to give Sindy the bike- on my honor, at all costs. I have issues about that sort of thing.
Then I got haircut, picked up some medicine for the trip (and my canker sores) from CVS, and set up the two hops using all four Bullets down the hallway outside the office in bldg 36. (Almost didn’t have enough Ethernet cables – had to scrounge from the other lab desks, again.) It worked fine, but was extremely slow: 3.29 mbps download and 0.73 upload, with original speed 58.96 download and 2.72 upload. I guess the halving of the throughput when you increase to 2 hops really makes a difference. One thing I didn’t test was the effect of the length of the Ethernet cable at the relay point on the connection speed. Now that I think about it, that could make a big difference; the data has to travel through every cable at the midpoint, so from BulletàinjectoràinjectoràBullet. I wonder how efficient POE is at transmitting data—the fact that we are also modulating the data over a DC power signal (I think) ideally shouldn’t make any difference. But any fluctuations in the DC power signal could also cause bit errors in the modulated signal.
Power over Ethernet also forces you to use Ethernet cables, which is easy but not very signal-efficient. I wish I knew more about radio equipment so I could engineer a solution.
More on what happened on Monday.
The last errand I’d scheduled for that day was to pick up the screw-on “butt” end of the first broadcasting Bullet from Tang, where I’d accidentally left it after testing on Friday, and to pick up my bike. It was an egregious error, by the way. Without the butt of the Bullet, it might not have been waterproof; we would have somehow created a solution, but it would probably have been makeshift at best, and would have wasted precious time and energy. Always keep track of every part of your equipment, even caps and screws and everything—you don’t want to be caught in the field without them.
It was drizzling when I stepped out of the office, and I was carrying nothing but my cell phone. I started running, although I found out later that I might have gotten wetter because of it. The rain started coming harder and harder; lightning cracked the sky and thunder rolled overhead. I counted the seconds – four miles away (to within an order of magnitude, anyway). I was pretty soaked and out of breath by the time I got to Tang, and the storm was getting closer by the minute. But after tucking phone and Bullet butt into a doubled plastic bag, I headed back out to bring the bike back for Sindy. Biking 1.5 km in a short skirt through stormy, flooding streets was quite the adrenaline rush. I squelched back to the Terrascope room dripping from head to toe. Luckily, I had a towel and change of clothes. I stayed with P that night.
Tuesday:
I was exhausted; I tested the system down the hallway (one hop only) using my MacBook as a router, and it worked fine! No idea what had happened that other time down Vassar St. Then I was supposed to go to Radio Shack to get supplies to repair Ethernet and coax cables with – crimp tools of the correct sizes, heat shrink, spare end connectors (N type, 8p8c). Instead, I crashed in the Terrascope room for 5 hours and that effectively ended the day. When I got up, I panickingly searched the web for the items I needed and ordered some of them with two-day shipping (because for some reason my confused brain thought it was still Monday). Instead of sleeping that night, I emailed out to the MIT radio society (w1mx) and MITERS mailing lists begging for N type end connectors, and watched as long as I could. It would have cost me $180 out of pocket to order the connectors and a crimp tool for them online, and they were only spare parts (for pretty important things nonetheless).
Wednesday:
J and I disassembled the antennas and packed everything away into 4 suitcases – 2 just barely less than oversize. We’d been worried about finding a suitcase for the huge 24 dBi antennas’ parabolic dishes, which were 2 by 3 ft and each came apart into 2 by 1.5 ft pieces, but our widest suitcase just barely fit them diagonally.
The MIT radio society also donated some spare N-type solder connectors (no crimp tool necessary)! Thank you, jhawk and w1mx!
All was well (except for maybe my canker sores). Both J and P brought me strawberry rhubarb pie to celebrate.
Thursday afternoon:
Traveling has been surprisingly light-hearted. We ran last-minute errands like binding the science lab manuals, and J made a trip to Radio Shack to get extra electrical tape and some 8p8c Ethernet cable heads that hadn’t arrived on time. I had pie and lunch with P right before leaving, which was great. J is also a very sunny person; I am lucky to be traveling with her.
Now coming into Amsterdam for a 4-hour layover (hopefully enough time to type this up, and maybe buy a real notebook?).
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