Basic Adjustment of the Polarmount Aerial

General

A polarmount aerial is constructed so that the imaginary line, on which the satellites are orbiting at a distance of 36000 km above the equator, can be followed by a single control func- tion of the motor.

There are a number of different motor types and motor fixings.

The action radius of the aerial (max. deflection to the east and the west) can be restricted by limit switches inside the motor, or by mechanical end stops. This is especially necessary to protect the aerial from running against obstructions (walls, trees, etc).

In addition, the receiver is provided with electronic limit swit- ches (similar to tab stops on a typewriter) for restricting the action radius of the aerial.

Attention!

It is not allowed to use these limits to protect the aerial from running against obstructions. If a test run should be necessary for adjustments at a later date, these limits would be overridden and the aerial thus could be dama- ged. The following illustration shows the relations.

mech. action radius of aerial

Motor

Motor

Position 0000 = zero point

Limit 1 e.g. 0020

Maximum stroke

restricted by electrical limit switches

or mechanical end stops.

mechanical or electrical end stop (East)

mechanical or electrical end stop (West)

 

 

 

 

Limit 2

 

set limits

L 2

L 1

e.g. 0650

 

 

 

 

 

(restricted action radius)

Different satellite positions

within the set limits.

63° 23° 19° 16°

In programme mode, the aerial runs

only to these positions,

not to the limits.

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Grundig STR 400 AP manual Basic Adjustment of the Polarmount Aerial, Mech. action radius of aerial Motor