Alfa glitches from dewar monitoring

02jun 12

     Periodic signals with 20 Hz periods have been seen in alfa data. This was traced to the alfa dewar monitoring system. Every 5 seconds the bias voltages and currents are read. This is causing glitches on the bias lines. The gain varies with these glitches.

27apr12: data with alfa cover on.

    On 27apr12 tests were done with the alfa cover on (to make sure that we weren't looking at externally generated rfi)
The setup was:
The processing was:
The plots:
processing: x101/120427/,

31may12: P2030 search data.

    P2030 pulsar search data from 31may12 was examined to see how strong the dewar glitches were.Since this was regular observing the alfa was looking at the sky.

The plots show the results for B1907+10(.ps) (.pdf):