GBT Support - Frequently Asked Questions
How do I reload the cabling file?
1. Open Cleo.
2. Launch IF Manager.
3. Under 'File', select 'load cabling list' (you will need gateway privileges to do this).
4. A browser should appear, select the default cabling file which is named 'standard.cabling'.
You might need to reload the cabling file if Astrid gives warnings like 'cannot route IF path', or related config-tool or IF manager errors.
How do I calculate a frequency switching offset?
To ensure that channels are properly aligned in the spectrometer use:
FS = BW / 2n
where FS is the frequency switching offset, BW is the bandwidth and n is an integer.
How do I turn off the L-band notch filter?
This may be an issue for anyone who wants to observe in the range 1,200 to 1,350 MHz.
The notch filter is set by the configuration and the default is to put it in. To turn it off, put the following in your configuration script:
notchfilter = "Out"Otherwise, every time you start up a script that does a configuration, it will put the notch filter back in.