1. compound pendulum? Do you mean something like [url=http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=195.0]double pendulum[/url]
2. compound and simple microscope? Do you mean something like  [url=http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=47.0]Thin Lens combinations[/url]
When you put something near focus point( A small object put in front of a len, let the image located near focus point of second lens, then it is a microscope.
Very far object will form image at focus point, let the image located near focus point of second lens, then it is a telescope.
You need to understand magnify lens first! Then, it is easy to understand how to make microscope or telescope.