27th November 2013 - The best laid plans...

4 February 2014 by Luke Jew

Nearby communications tower which we won't be using to do beam tests from!

Angela and Mike took me (Luke – their new Dphil student) to HartRAO in November where we met up with Charles for an intense two weeks of commissioning.

For the first half of our visit things went to plan. We got rid of some high system temperature features at around 5.3 GHz which turned out to be caused by radiation leaking through little thermal breaks inside the cryostat. We stopped this leakage with a bit of cutting and sticking of loaded silicone absorber - I never would have guessed that my first trip to a telescope as a graduate student would require so much arts and crafts! The top of the secondary mirror hadn't stood up to the weather and so a slight change in design was needed – which again required cutting, sticking and also lots of expanding foam!

Finally we put the receiver back onto the telescope and with our fingers crossed, pointed the telescope at some bright radio sources. This is where our initial timetable wen the way of the most well laid plans of mice and men... astray! Sadly strange signals started appearing in the data. It was literally with minutes to spare before we had to leave for our return flight that Mike sussed out what was wrong... I guess we will be sending Jamie and Charles up to sort out those spurious signals in the new year.

Part of those initial plans involved doing beam tests by blasting a signal at CBASS from a radio horn. We performed all the ground work: Constructed a rig to hold our massive radio horn in place and held on for dear life whilst doing lots of bumpy driving in a 4x4 into the nearby wilderness before climbing over birds nested in an old communications tower to find the perfect spot from which to broadcast our signal. This means I'll need another trip out to South Africa to finish the job (It's a hard life!).