Day 85, 8/21/2012 -- EBEX, now with 100% less BTS!

Today we ticked a few of the miscellaneous items off our pre-disassembly to-do list. Jeff and Kyle tested some HWP system commands, Shaul and I did measurements of our mirror positions at different elevation angles, and Kevin and Kate took more detector noise data. Kyle also started setting up the SIP simulator, which we will use once CSBF removes the SIP from the gondola for thermal vac testing.

On the disassembly front, we started removing some more of the major sub-assemblies of the experiment. I forgot to mention that yesterday we removed the radiator panels for our detector electronics liquid cooling system. Today, we removed the Baffle/Triangle Support (BTS), the tubular frame that surrounds the whole experiment and provides a structure which we will cover with aluminized mylar in Antarctica. Once the antennae from the top of the BTS are disconnected and removed by CSBF, we can disassemble the BTS and start packing our large shipping container.

On a slightly different note, I was able to fix the BLAST group's helium leak checker with help from a gentleman at Laco Technologies -- we were video chatting via Skype and he was able to diagnose the problem immediately, within seconds of the leak checker turning on. He guided me through the repair process and a half hour later we had a working leak checker. Good thing too, because otherwise we would have had to rent one at considerable expense.

Pictures from today:
https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120821

Day 84, 8/20/2012 -- Gold, Frankincense, and MRR

We finished our compatibility test just in time for the Antarctic LDB Mission Readiness Review, or MRR, this morning. As part of this review, the science payloads going to the ice have presentations on their status and various other issues (personnel, schedules, etc) pertinent to their campaigns. EBEX's review went well, and we fully expect to have no problems once we get to McMurdo (hey, we can dream, right?).

After the MRR, we had a discussion about the remaining outstanding items to test before we disassemble and start packing up the experiment to ship. There is a range of pointing (and especially star camera) related stuff as well as a few smaller receiver/telescope items on the list along with further analysis of our detector array's performance.

One of the items on the list was more time constant measurements -- during our previous measurements, we only took data in our lowest frequency band, so we wanted to extend that up into the higher bands. Also, our previous measurements showed some weirdness so we changed the source modulation to try and figure out the source of the problem. It turns out that changing the modulation from an electrical chop of our narrowband source to a mechanical chop of the source with an interrupter wheel made it so we could make measurements at all three bands simultaneously! The data from this test look promising.

As part of this test, I had to climb up and down the gondola quite a bit, and at this point I'm getting pretty good at it.

No pictures today.

Day 83, 8/19/2012 -- Compatible Now

After many days of testing, EBEX has finally passed its compatibility testing. Yesterday we gambled with the weather, trying to squeeze in whatever testing we could in between breaks in the weather. We got most things done yesterday, but since we didn't finish we left EBEX in the "Tim Shed", the large open building where the launch vehicle parks. Conveniently, we still had line-of-sight uplink/downlink, so the pointing crew was able to do some things overnight (though not actually point the gondola).

We awoke this morning to an absolutely beautiful summer day, with clear blue skies and quite moderate temperatures. Since the gondola was already hanging from the launch vehicle, it was quick business to disconnect from wall power and get the gondola moving. We parked outside the high bay and we finished with the "compatibility" part of the day by about 10 or 10:30AM. We then continued to hang while Chappy and Joy did some pointing test, we took some sun sensor calibration data, and Matt and Michele tried to diagnose an odd problem with the liquid cooling system pump motors. Still, we were back in the high bay by 2 PM, at which point we refilled all the cryogens in the cryostat and began a fridge cycle.

Pictures from yesterday:
https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120818

Pictures from today:
https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120819

Day 81, 8/17/2012 -- Compatibility, soon?

Sorry for the late update...CSBF got their SIP issues worked out and told us they were ready to try again for compatibility Saturday morning. During the day we managed to keep ourselves occupied.

Now it's Saturday morning and it's raining and thundering all over the place. We're waiting for a break in the weather, perhaps in a few hours, where we'll get a window to roll out.

No pictures this update.

Day 80, 8/16/2012 -- Compatibility, brought to you by goldfish crackers, big marshmallows, and Coca Cola

Wow, what a long day. As of now I've been up for about 35 of the last 38 hours trying to help facilitate our compatibility test. In the end, we ran out of time due to some nagging issues with the CSBF hardware, but we made a lot of good progress and hopefully will be able to complete our compatibility testing in a few days once the hardware is ready and the weather cooperates.

I'm not going to post a detailed run-down, but I do have a lot of pictures ranging from our 10AM to solar panel tests to our pickup at 10PM to various parts of our rollout to being set out on the pad at about 5AM the next day (today). I don't have any pictures from after that, but it looked pretty much the same the whole time, and the night-time shots are more dramatic anyway :)

Pictures:
https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120815

Day 79, 8/15/2012 -- Compatibility, ongoing

Short update today: We're currently in the middle of our compatibility checkout (at nearly 6AM after having started at 9PM or so). I'll give details and post lots of pictures later...presumably after I will have gotten some sleep sometime today.

Day 78, 8/14/2012 -- Weigh Day

Today was another productive day in the EBEX universe. We did some more noise tests, we got the battery commanding system working (our batteries are a little different than normal batteries, and have some internal circuitry that we can interface to), and we weighed the experiment for the first time in who knows how long. Right now it's looking like we'll be about 100 lbs under our weight limit -- not bad!

Tonight will be the last (hopefully) of our water tower scans. We attempt compatibility (weather permitting) starting tomorrow night.

No pictures today.

Day 77, 8/13/2012 -- The only constant is change

Today, I didn't have to climb anything once! Kate spent some time climbing on the gondola to debug some DfMUX board issues while I bounced around doing various things and talking to people about our upcoming compatibility test and some issues for our Antarctic campaign. Toward the end of the day, we took some more time constant test data with our chopped source.

Andrei was a veritable one-man beehive of activity today as he tried to finish the mounting of the liquid cooling system radiators before he left today to catch a red-eye back to Rhode Island. And he succeeded, I might add!

I have uploaded some pictures from yesterday and put the link in yesterday's post -- go there if you want to see 'em!

Pictures from today:
https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120813

Day 76, 8/12/2012 -- Up and down

Up and down in the very literal sense, for me anyway. I spent most of today climbing up into and down from the gondola to help Kevin and Kate with some measurements they were doing, and then at the end of the day had the joy of climbing the water tower with Jeff with a 30-lb power supply in my backpack and then hanging out up there for the next 3 hours. It was a productive, but very long (10:30AM to 3AM) day at the base. In fact, I should be asleep, but I needed to write this post first!

Elsewhere in the high, Michele spent a lot of time making a power cable for us to use while we are hanging from the launch vehicle, and Andrei made a lot of progress in the mechanical mounting for the liquid cooling system radiators.

I have pictures, but I'm too tired to deal with them right now so I'll post them tomorrow (later today, actually).

EDIT: Pictures!
https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120812

Day 75, 8/11/2012 -- Like lotto, you got to be in it to win it

I don't know why that line came into my head -- perhaps it's because I'm quite sleep-deprived, having woken up at about 4:30AM in order to catch my early flight from Minnesota down to Texas. Of course, this means I'm back in Palestine!

A lot has happened in the nearly 3 weeks I've been gone. Many many scans have been made of the source on the water tower, whose data are helping us understand the EBEX optics. The big push right now is to do our "compatibility test" with CSBF to ensure their and our systems play nice with each other. There has been a ton of activity over the past few weeks that I've missed out on, but the gondola itself hasn't changed too much -- the solar panels are now wired up and installed, some components for the liquid cooling system have been mounted, and basically all hardware is in place for compatibility. We're going to try and take some more data in the next couple days and then switch over completely to doing our compatibility test.

Elsewhere, the BLAST team has done their compatibility test and have basically disassembled and packed up their entire experiment. They did, however, implement a fix in their cryostat and are now checking to see if it worked, but it's likely they won't be here for more than about a week.

https://picasaweb.google.com/104253244018605213307/EBEXInPalestine20120811