Rohde & Schwarz SCV8000E/R System Manual Download Page 150

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Chapter 5

Operating

2104.6536.72

- 5.68 -

E-1

3. Point to the right margin of the diagram with the mouse and set the last point.

Input mode will be terminated and you can now edit the curve as required (see the sec-
tion "Editing the characteristic").

Loading an existing characteristic curve

Instead of creating a characteristic curve from scratch, you can load existing curves into the
drawing level and edit them as required. There are three possibilities:

– Select

Preset Curve

in the contextual menu. A preset curve highlighted in the program

is loaded into the display level (

blue curve

). Now, using the

Edit Read Curve

contextual

entry, transfer the characteristic curve into the drawing level (

red curve

– Use the

Curve Data xxx Read

function to load the current characteristic curve from the

precorrection memory straight into the drawing level (

red curve

– Load an existing precorrection from a file using the

Storage

function from the Navigator

window for transmitter operation.

– In the

RF Out

Precorrection

menu window use the

Restore Current Setting

Re-

store All Settings

parameter to reactivate the original precorrection curve (factory set

precorrection) in the instrument. Then in the precorrector GUI use

Parameters

Res-

can

to update the display. The original precorrection curve is displayed.

Note

You may have to fetch the read precorrection curve with the Show Read Curve contextual
function into the foreground so it can be viewed.

Editing a characteristic

Characteristics are edited based on the points they contain. Each point in the database con-
tains the following information: x value, y value, slope and locking of the slope. The number
of points is variable.

The characteristic is computed using one or more sectionally defined spline functions with
a specified start-point and end-point slope on the edges. The edges are considered to be
the right or left edge of the graphics as well as fixed points. A fixed point (recognizable by
a triangular symbol) "freezes" the slope of the curve. Like normal points, fixed points can
also be moved later on, but the slope due to the fixed point stays unchanged.

Existing points are

edited directly

. You can shift them with the mouse in the x and y direc-

tions (click and drag). Double-click to lock them (or to unlock them).

You can use the

contextual menu

to add and delete points and to lock and unlock their

slope. The procedure is as follows:

–

Set Point:

1. Select the

Set Point

function.

2. Using the mouse, set a new point on the curve.

–

Delete Point, Lock Point and Unlock Point:

1. Select the desired function.

2. Click on an existing point.

For fine setting of the characteristic, there is a

navigator window

available which can be

called up from the contextual menu. The navigator window can be used to set the point co-
ordinates and the slope (fixed points only) as numerical values. The procedure is as follows: