I am fortunate to have a large terrace at home where I have been able to install two observatories: a rotating dome and a clamshell dome. But the building itself by its orientation blocks the visibility of any celestial object to the south with altitude below 30 degrees, and this year 2021 is especially interesting for the observation of the mutual phenomena of the Galilean satellites of Jupiter, which occur precisely at low altitudes and in south orientation. Also the southern orientation facilitates solar observation, especially in winter when the sun is lower. For these reasons, I decided to take advantage of a south-facing window and to build a fixed observatory on a window ledge.
The window's ledge is not the best place to place a telescope, but if there is no other option, I have found that it is an alternative that works. First of all you have to keep in mind the safety aspects: you have to check that the window post can support the weight of the column, mount and telescope, you have to secure everything very well and in my case I have been able to do it because what is under the window is my own garden.
The first step is to order a metal plate that extends the length of the support so that the movement of the telescope does not touch the window, and also allows to have a horizontal surface since the support as it is logical is inclined as it pours water. The metal sheet must be thick enough to prevent it from sagging and to avoid transmitting vibrations to the telescope. To fix it to the pole we have used "L" brackets and 6 bolts of 10mm to guarantee a very secure fixation.
Vibrations are the main problem of this installation. In addition to the sheet metal being thick enough, I have placed at the end a fixation with rubber buffers to absorb them. In the photo you can see the idea.
Once the metal plate is securely fixed, correctly leveled and blocking vibrations at the end, we can place the telescope. In my case I have used the column of an AZEQQ5 mount, and the mount is placed on it. It is a system that allows a fixed station setting (the column must be left permanent) and the mount can be put on or taken off maintaining a reasonably good alignment.