Travel Diary – USA – Digital Comms Conference – Appendix

Some stuff I forgot about the digital communications conference. Bdale I believe it was showed me an antenna plot that someone in AMSAT had made recently. It was a plot of the antenna gain for the GPS transmitting antenna as you change direction.

This is information that AMSAT has asked the US Navy for a number of times, each time being told that the information was classified. Well, it is no longer classified, since AMSAT have experiementally determined what the plots look like. Funny thing is that they look exactly what I thought they would look like being an end-fed helical.

The plots do prove something though. The GPS antennas are pointed to earth. But you can receive the signals from behind the satellite in outer space. With some modified software in the GPS receiver, you can actually use GPS many many thousands of KM from earth.

The other thing is that there are plans for AMSAT to launch a space probe. They have done a lot of work on satellites on earth, but now they are looking at sending a probe to Mars. There are some unknowns here, but they hope to have it launched by the end of the decade. One of the problems would be that you only have a launch opportunity every couple of years… And if you miss it you need to wait until the next on.

Then again there is also the feeling in AMSAT that even if you miss getting to Mars, then there is still science to be done. Sending a probe just out into space missing the planets all together would still be a success.

[Oh, Right now it is 3:05AM local time, and 12:05PM Sydney time. I woke up and decided that writing my blog/diary would be better than just lying there.]

Oh, and I have some more comments on Heathrow. I expected it to be busier and bigger. At least international arrivals in Terminal Four. My impression is that Auckland International Airport international arrivals is busier. Maybe just at the correct times of the day. But even so. Having the EU arrivals come into other terminals does not help the distortion, and neither does having only seen arrivals. Arrivals always seem to be quieter than departures.

Not sure what went on in the early hours of Wednesday morning, but there was a light plane circling the hotel, and also one or two choppers in the area. Nothing on the BBCWorld News this morning. May have been something more localized and more minor.