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README.md

+# Overview
+
+This is control software intended for small radio telescopes, such as the 
+[Haystack Old SRT](https://wikis.mit.edu/confluence/display/SRT)
+or [New SRT](https://www.haystack.mit.edu/haystack-public-outreach/srt-the-small-radio-telescope-for-education/)
+
+The software is made of two parts: a server and a client. The server is
+plugin-based and must be supplied with the implementation of the control logic
+for the particular hardware configuration.
+
+Currently, the only hardware plugins supplied here are for used with the
+*Old SRT* (CASSI mount, digital receiver model). It is highly recommended
+you update the STAMP controller with the firmware with fractional count support
+[SRT Memo 22](https://www.haystack.mit.edu/wp-content/uploads/2020/07/memo_SRT_022.pdf).
+
+Plugins for the SPID Elektronik Big RAS drive and MD01 controller, as well
+as the Measurement Computing PCI-DAS4020/12 A/D converter are currently in a
+rudimentary state and will be added some time in the future.
+
+A radio telescope simulator plugin is available and the default configuration
+when the software is installed.
+
+
+
+# Building and Installation
+
+Follow the usual autotools routine, i.e.
+
+
+```
+./autogen.sh
+./configure
+make
+sudo make install
+```
+
+The default configuration of the client software points to the server running
+a (modified) *Old SRT* at the Department of Astrophysics at the University of
+Vienna. If you want to run the simulator, you must download a HI data file
+(*sky_vel.dat.*, available as .gz or .zip) from
+[here](https://www.univie.ac.at/radio/files/), **unpack it** and place
+it in the **directory** the server is executed from, which in typical UNIX
+systems is your home directory, if you launch the server via the desktop icon,
+or in the current directory, if you launch it via the console.
+
+If the simulator won't start, make sure to try to launch *radtelsrv* (server/simulator)
+from the command line for extra debug info.
+
+
+## OSX
+
+There is currently no installer for OSX, see HOWTO_OSX for a list of instruction
+how to set up a build environment and install the software.
+
+## Windows
+You can build this software on Windows via MingW, but you may also download
+a pre-built windows installer (.msi-file) [here](https://www.univie.ac.at/radio/files/)
+
+**NOTE:** On Windows, the (extracted) simulator data must be placed in the base
+installation directory (usually C:\Program Files\radtel), NOT in the bin/
+subdirectory!
+
+
+## Connecting to the simulator
+
+Once you have manage to successfully install the software and data file,
+launch *radtelsrv* (server/simulator) and the client (*radtel*), then configure
+the host by clicking *cog wheel* at the right side of the top menubar and
+change the *Host* entry to *localhost*, the click the *Reconnect* button
+at the bottom of the menu or restart the application.
+
+
+
+# How to use the client software
+
+This section will be expanded at a later date. For now there are only basic
+pointers.
+
+## General
+
+The buttons in the left corner of the menu bar can be used to disperse and
+collect the tabs of the client.
+
+The button with the cog wheel icon opens the configuration menu.
+
+The status field at the botton shows the current status of the telescope,
+such as position, slewing or spectral acquisition. It can be hidden by
+clicking the expander button in the bottom right corner of the window.
+
+## Chat and Log
+
+...should be obvious
+
+## Sky View
+
+![SkyView](./screenshots/sky_view.png)
+
+This is a map of the currently visibly sky at the location of the remote
+telescope in polar projection, with north at 0 and south at 180 degrees
+(on the northern hemisphere). The zenith is the center of the diagram.
+The dashed blue line and solid outline represent the plane and
+approximate outline of the Milky May. Circles indicate catalogue objects.
+The red line indicates the physical movement limits of the telescope, while
+the green line (and shaded are) represents the local horizon (building, trees,
+etc.)
+
+When the mouse pointer hovers on top of the map, the current coordinate info
+below the cursor is printed in the top right.
+
+The time of the projection can be shifted by *right-click and drag*.
+
+*Ctrl + left click* commands the telescope to drive to that position. If a
+catalogue object (disk) is clicked in this manner, the telescoped will move
+there and in addition, *tracking* will be enabled.
+
+If tracking is enabled, *left-click* anywhere within the sky map will de-select
+the object and deactivate tracking.
+
+## Spectrum
+
+![Spectrum](./screenshots/spectrum.png)
+
+If acquisiton is enabled, shows current and cumulative average spectrae.
+The gui elements should be mostly self-explanatory, here are the key/mouse
+bindings:
+
+*left click and drag* to define a zoom box
+*scroll wheel* for two-axis zoom
+*shift + scroll* for Y-axis zoom
+*ctrl + scroll* for X-axis zoom
+*lower case "a"* to autoscale
+*Ctrl + left drag* to fit a gaussian to the selected datums
+*lower case "u"* deactivates the gaussian fit box
+*alt + click* to define new center frequency for spectrometer
+
+There is also a right-click popup-menu for extra functions.
+
+
+## Telescope
+
+Configure the telescope position. Click *Get Coordinates* to update the
+control fields in this tab with the current status of the remote telescope.
+The remaining functions should be obvious if you have used any telescope before.
+
+## Spectrometer
+
+![Spectrometer](./screenshots/spectrometer.png)
+
+Configure the spectrometer. Click *Get Configuration* to update the
+control fields in this tab with the current status of the remote telescope.
+
+The remaining functions will be described in more detail at a later date, but
+be warned of one thing: do not set the acqusition frequency range too wide.
+This will work without problems with the simulated radio telescope, but
+in real systems, spectral acquisiton takes time and extreme configurations
+can lead to hours of wait time. See the *REC* status field for the ETA
+of the next spectrum. If it is excessive, you may have misconfigured the system.
+In such a situation, you should scroll/go to the bottom of the tab and
+deactivate *Spectral Acquisiton*, then reconfigure the *Acquisiton Frequency Range*
+to a much smaller (typically a few MHz) bandwidth and re-enable.
+
+
+## History
+
+The plot on the top will show the *continuum vales* (integral) of
+previously recorded spectra, the waterfall diagram on the bottom will show a
+colour-coded spectral history. You can use the level slider on the right
+to somewhat adjust the colour cutoff.
+
+
+## Observation
+
+These are automated observation programs. Their function will be described at
+a later date. You're welcome to find out yourself tho.
+
+
+
+# How to use the server software
+
+## Simulated Telescope
+In the default configuration, a radio telescope simulator plugin is enabled
+and will show you a control interface once started.
+
+![SimPlugin](./screenshots/server_with_simulator_plugin.png)
+
+
+To the left, you see an image of the HI emissions of the Milky Way given the
+current configuration of the telescope. You can modify the colour cuts of the
+image by changing the sliders just to the right. If you want to set
+cuts in the VLSR, change *Vmin* and *Vmax*, the click *Redraw*. Note that
+this will only influence the data range from which the displayed image
+is generated, but never cut off the simulated data generation range,
+which will always range from +400 to -400 km/s.
+
+To change the simulation parameters, refer to the entry fields on the right.
+Any change to an entry (either via the range buttons or manually followed by
+enter key/changing the field) will result in the immediate reconfiguration
+of the simulated telescope.
+
+*Rbeam* sets the simulated beam radius for the simulated resolution
+*TSYS* sets the system temperature
+*Sigma* sets the amount of simulated nose
+*Eff.*  is the efficiency of the telescope.
+*LAT* and *LON* set the geographical location of the telescope
+*Rate* sets the simulated spectrae per second
+*Sun* sets the current radio flux density from the sun.
+
+
+## Actual Hardware
+The server configuration for actual hardware can be a bit tricky. If you own
+one of the Haystack SRTs, you're welcome to mail me for some help.
+
+
+# Experimental Features
+
+If you'd like to try the freely programmable observation mode implemented
+via [GtkNodes](https://github.com/aluntzer/gtknodes), install the library
+and build the client from the *gtknodes* branch.
+
+You will find the *Node Editor* in the *Observation* tab. To show the available
+nodes, right-click the node view for a popup-menu.
+