Ametek 7280 Instruction Manual page 41

Once the required value is set, there are two choices:
If the (enter) key is pressed, then the value entered will be accepted as the new
control setting, the setting will be shown in normal, bright, text and the keypad icon
will be removed. If however the ABORT KEYPAD key is pressed, then the control
will be left at its previous setting and the keypad icon will be removed.
The following example should make this clear.
Example: Setting Internal Oscillator Frequency to 100.3 Hz
If the internal oscillator frequency is 1000 Hz and it is required to change it to
100.3 Hz, then press the front-panel SET CONTROL key followed by the key
adjacent to the Main Display OSC FREQUENCY control. The keypad icon will
appear and the keypad will be activated.
Press the keys corresponding to the digits "1", "0", "0",
oscillator frequency to 100.3 Hz. Finally, press the
and remove the keypad icon.
Active Cursor XE "Active cursor"
In some cases it is useful to be able to quickly adjust a control in equal increments,
for example when monitoring the effect of changing the oscillator frequency about a
given value. This is easily done in the model 7280 using a control setting feature
known as Active Cursor operation.
A cursor can be placed under any digit of a displayed control where that control
requires numerical data entry. Thereafter, the
increment or decrement the setting of that digit.
The positioning of the cursor can be done in one of two ways:
Using Cursor Movement Keys
The , , and
digits to which it can apply on the relevant controls. The keys
the position of the cursor within a control while the
between controls.
This method of cursor positioning is very easy, but for compatibility with other
SIGNAL RECOVERY lock-in amplifiers, particularly the models 7220 and 7265,
the double key-press method of cursor positioning is also included.
Using the Double Keypress
Step 1 Simultaneously press both sides of the
the example shown in figure 4-3 the internal oscillator frequency will be
adjusted, since this is the control displayed adjacent to the keys. A cursor
appears under one of the displayed digits (see also figure 4-4).
Step 2 With the cursor visible, repeating step 1 causes the cursor to move to the left.
When the cursor reaches the most significant digit available (left end of
control setting) the next key-press returns the cursor to the least significant
digit (right end of control setting). Continue this action until the cursor is
under the required digit.
Chapter 4, FRONT AND REAR PANELS
cursor movement keys move the active cursor between all
and "3" to set the
key to accept the value
keys adjacent to the control
and keys adjust
and keys move the cursor
key adjacent to the control. In
4-3