Interferometer FAQ

So the interferometer is not working as you expect, right? Hopefully this page will answer your question or, at least, get you pointed in the right direction

Q: The dishes don't move when I use point2.

A: First check the power, there is a power strip on the wall behind the electronics, make sure it is turned on. When you turn it on you should hear some "clicks".

Secondly, make sure that the computer you are using is connected to the ugastro computer network. Moving the dishes involves communicating with the computer quasar (

Q: I run startchart but I keep getting errors about connecting. What is the problem?

A: Most likely, the GPIB connection is not running or not functioning properly. If it is running, close the open window on Mira (the windows PC). Now double click the shortcut on the desktop named "gpib_705.tcl".

Q: I am recording data but there doesn't appear to be any signal, what am I doing wrong?

A: There are three things that could cause this behavior. The first check should be to see if the dvm is plugged into Mira (the windows PC) via a GPIB cable. This thick cable connects the back of the dvm to the gpib card in the back of the PC. If the dvm displays the same values as recorded then that connection exists and is functioning properly.

The second explanation is that you are trying to observe a very faint source at 12 GHz. The sun (best bet) and moon (second best bet) are bright sources, point to one of them to determine if your system is behaving as you expect

The third explanation is that the dishes are not pointed correctly. Make sure that the dishes are not homed and are pointed where you think they should be.

Q: I get an error reading the digital voltmeter as the following:
% SOCKET: File unit is already open. Unit: 7

A: A previous IDL command that was reading the DVM did not close properly, at the IDL prompt type: close, 7.

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