The present invention relates to a telescoped equipment carrier which, for example, can be adjusted as to elevation and locked in the projected disposition, and more particularly, the invention relates to an antenna structure which can be hydraulically or pneumatically operated for its extension.
Hydraulically operated antenna masts are known generally. They are used mostly in mobile equipment for each set up or even placement in locations which are to be varied. The known systems have indeed the advantage that they can be positioned and set up quite rapidly; still, they are not well suited, for example, for setting up a radio link. For example, temperature variations do, in fact, change the height of the mast quite considerably. A temperature variation of 20.degree. centigrades and more is not unusual. If the deployment height is about 20 m (65'), such temperature change may produce a significant change in height and the change does, in fact, render the radio link inoperative. Also, hydraulic actuation carries with it always some leakage problem so that one has to add some liquid from time to time, particularly to keep constant the adjusted protraction height. For exactly that reason, mobile military antenna masts use mechanical devices which can be erected and folded up again or are cranked up etc., in spite of other drawbacks these devices have, namely construction which is cumbersome to work with.