B&K 4070A Manual Do Utilizador

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BK Precision 4070A User Manual Rev.2.2 
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3.0 Operating controls and keys. 
3.1   Mode key  
   The Mode key is used to change the operating mode of the 4070A. When pressed, the LCD display is cleared and 
the question Mode? is displayed.  
  The Mode key acts as a shift type key in that the meaning of each button on the front panel changes to that 
described by the red wording beneath it.  To enter Sweep mode, for example, first press the Mode key and then 
press the number 4 key.  
  You can exit the Mode screen by pressing the red Mode key again. The display returns to the previous mode 
unchanged. Some modes are available on the 4070A that are not printed on the front panel. To access these modes, 
press the Mode key, and then the Clear key to bring up a scroll menu from which you can select one of these extra 
modes.  
3.2  Field arrow keys 
  Field arrow keys are used to move the cursor to the numeric entry field that you wish to edit. Each time the key is 
pressed, the cursor is advanced to the next field on the display.  A flashing character indicates the cursor position.  
   When the cursor is advanced to a new field, it is placed at the last-used position within that field.  You then use the 
è or ç keys to move the cursor side-to-side within the field.  
   One of the valid cursor fields is "off".  When the cursor is off, (i.e. there are no flashing characters anywhere) then 
all numeric values are frozen and cannot be changed until the cursor is switched back on.  This feature is designed as 
a "lockout" function to safeguard parameter values from being changed by inadvertent key presses or turns of the 
rotary knob.  
3.3   Recall / Store key  
   Recall/Store key is used to store or recall an instrument setup to or from 10 storage locations in non-volatile 
memory. By using the Store/Recall function, you can save all operating parameters so they can be quickly recalled 
even though the unit had been turned off.  The offset voltage and currently selected RS232 baud rate are also saved.
 
   If the instrument setup is saved while the unit is in Arbitrary Waveform mode, the currently loaded arbitrary 
waveform is stored to nonvolatile memory. Although mode parameters such as Clock Frequency, Level, etc. can be 
saved to 10 locations, the arbitrary waveform is always saved to/recalled from a single location. The entire 
waveform array of up to 32,768 points is saved.
 
   To recall an instrument setup, press the Store/Recall key once. The LCD display will be cleared and the question:  
Recall (0-9)?  Will appear, asking you to press a numeric key 0 to 9 to select one of ten available locations to use. 
You can abort this question without saving a configuration by pressing any key other than 0 to 9.  If you then press 
the 5 keys, for example, the display will show Configuration recalled from location 5 to confirm the recall 
operation.     
   To save an instrument setup, press the Store/Recall button twice. The LCD display will be cleared and the line  
Store (0-9)? will appear, asking you to select one of ten available locations to store the configuration. You can abort 
the question without recalling a configuration by pressing any key other than 0 to 9.  
   NOTE:  Location 0 is special.  The instrument state stored to location 0 will be recalled on power-up. This 
includes the serial port baud rate. 
3.4   Offset key 
   The Offset key is used to specify a DC offset voltage to be added to the output signal. When this key is pressed, 
the LCD display is cleared and the cursor is placed in a numeric field to enter the offset voltage. Both positive and 
negative voltages can be entered.  
   To exit the offset entry screen and return to the current mode, press the Offset key again. The offset voltage value 
can be entered in the same manner as any other numeric value.  You can also use the wheel to modify a particular 
digit in the value.  Any voltage within the range of -6.0 to +6.0 can be entered.  
   NOTE: The offset voltage specified is a 50O load value. This is the voltage that will appear across a 50O load 
connected to the SIG Out connector.  If you are connecting the output to a high impedance load, the output voltage 
will be twice that entered.