Robert C. Byrd Green Bank Telescope
NRAO Green Bank
21st March 2002
GBT Software Project Note 19.3
This document describes how GO has implemented switching signal schemes.
The switching signals can be set either by a single button - the GO
switching signal keyword - or by setting each individual YGOR parameter.
This document will be primarily concerned with the interaction of
these two methods of setting the switching signals.
N.B. GO does not currently implement polarization switching.
Polarization switching is included in this document to provide a rough
outline of how it might be implemented in the future.
- 4th February 2002
- Initial version.
- 7th March 2002
- Add warning in abstract that GO does not currently have
an implementation of polarization switching. Add the history section. Added
switchDeltas and xferState to list of YGOR switching signal parameters.
Changed the list of possible switch_mode values: added information on
beam and polarization switching; added GO FITS keyword values; removed
``Switching'',``Switching, No Cal.'', ``Symmetric Switching'',
``Sym. Switching, No Cal'' and ``Symmetric Total Power''; added
``Freq Switch, 01'', ``Freq Switch, 12'',``Freq Switch, 0102'',
``Freq Switch, User Def.'', ``Beam Switch'', ``Beam Switch, User Def.'',
``Pol. Switch'', ``Pol. Switch, User Def.'', ``Freq Switch, 01, No Cal'',
``Freq Switch, 12, No Cal'',``Freq Switch, 0102, No Cal'',
``Beam Switch, No Cal'' and ``Pol. Switch, No Cal''. Added information
on GO's setting values of additional YGOR switching signal parameters.
GO not longer determines the switch_mode at startup but assumes that it is
``User Defined''. Add information of what happens to GO's switching
scheme if YGOR managers are reset. Remove section on ``Beam, Frequency
and Polarization Switching.''
- 14th March 2002
- Add section on position switching and when LASTON
and LASTOFF are reset. Also add section on what keywords are changed when
switch_mode is changed.
- 21st March 2002
- Added the forgotten ``Total Power With Cal, Spectral
Processor'' mode. Fixed errors with the cal_ctrl switch being omitted
from the mode definitions.