Yes I have,but there are 4 or 5 points where it is possible to connect it..
The ohm meter can be a critical tool for figuring out how to hook it up.
(1) An attenuator like this usually has 3 connections - input, output, and common ground.
(2) The resistance from input to common ground should be constant and equal to the rated impedance of the attenuator. So, if this is a 100k atttenuator, the resistance from input to common ground should be 100k.
(3) The resistance from output to common ground should vary with the setting of the switch.
Your challenge: use your ohm meter to find the three terminals that have the desired properties.
I tried googling based on the string "24 step attenuator" and found many references. You might want to study up on the topic.