Spectrum Master™ User Guide : Secure-Environment Workplace : Option 7, Secure Data Storage
 
Option 7, Secure Data Storage
Option 7, Secure Data Storage, sets the instrument to allow saving information only to an external USB flash drive. Saving to the internal memory is disabled. When Option 7 is installed, it is effective immediately and cannot be turned off. In order to turn off Secure Data Storage, the option must be removed from the instrument by a service center.
Caution
Note that even with Option 7 enabled, operating parameters (such as frequency range and power level that are set by the user) remain stored in the Spectrum Master EEPROM when the instrument is turned off. These parameters can be erased, however, via a Master Reset operation, as described in Erase All User Files in Internal Memory.
Frequency Blanking
Option 7 allows you to hide the displayed frequency values. Frequency values displayed on the screen and menus are replaced with ##.####. To enable frequency blanking press the Shift key, then the System (8) key. Press the System Options submenu key, then the Reset submenu key. Press the Frequency Blanking submenu key so that On is underlined. Setting Frequency Blanking back to Off will preset the instrument to factory default settings.
After frequency blanking is enabled the instrument user is not able to restore the frequency readouts. Following is a list of the security measures that have been taken to protect the frequency information after Frequency Blanking is turned on.
1. Turning off frequency blanking presets the instrument (and the frequencies) to the factory default settings.
2. Turning off the instrument presets the instrument to the factory default settings and turns off frequency blanking.
3. Presetting the instrument turns off frequency blanking and restores the factory default settings.
4. Option 7 is designed to ensure that user files and calibration files cannot be stored in the internal memory of the instrument.
Warning 
Note that when Frequency Blanking is turned on, user files can still be stored and saved to an external USB drive, and that frequency information is not blanked in those files. Also, frequency information is not blanked from the SCPI commands that are used to remotely control the instrument.