Next: Focusing the Telescope
Up: Observing Guide for Pulsars
Previous: Back of the Racks
- Check the levels on the meter on the front of the filter bank you are
using. You should use the variable attenuators to set these 1/10 of a full
- Call the controller on the intercom by dialing 19, or on the phone by
- Ask the controller to drive to a bright source such as 3C274, 3C405 or
3C461. You can get a list of calibrator sources by typing psrcal 1 on
arthur and entering a parameter file eg 600timing. The list is also
shown in Section 6.
- Adjust the gain on the chart recorder so that the pens come about 2/3
of the way across when on source and then sit near the zero line when you
unplug the IF inputs.
- Then, with the inputs unplugged, adjust the zero levels so that the
pens sit on one of the dark lines on the paper - it is useful to offset the
2 pens by an inch or so.
- Check the levels when you plug the inputs back in and
iterate the last 2 steps if necessary.
- Flick the cal on and off and check that you can see it clearly on the
- Remove a db of attenuation to compare the marks on the chart
recorder with those made by the cal to check that the cal is a suitable
level. We usually use 0.6-0.8 of a db.
Sun Aug 17 17:32:08 BST 1997