IBM 7220, Instruction Manual

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4-5
Chapter 4, FRONT AND REAR PANELS
Figure 4-8, Setup Menu Mode - Left and Right-hand LCD Displays
In the setup menu mode, the left-hand SELECT keys adjacent to the left-hand
display cycle through a series of twelve setup menus. In general each menu allows
three controls to be adjusted, one via the right-hand side of the left-hand display and
the other two via the right-hand display. The setup menu description is shown on the
left-hand side of the left-hand display. Figure 4-8 makes this clear and the various
menus are discussed more fully in chapter 5.
When in the setup menu mode a further single press of the MENU key returns the
instrument to the normal Main Display mode.
4.1.06 90º Key
This key increments the reference phase shifter by 90º each time the key is pressed.
4.1.07 SET Key
This key updates all frequency dependent parameters within the lock-in amplifier.
Press this key after any change to the External Reference frequency.
4.1.08 Right-hand LCD Display Panel
This panel is normally used to display two out of the set of fourteen possible
instrument outputs, with the keys on each side of it being used to make the selection.
In this mode it is also used to allow adjustment of the level of the output offsets
applied to the X and Y outputs. In addition, the panel is used in the setup menu mode
as described in section 4.1.05 above.
In the normal mode, the panel is divided vertically into two sections, with the output
descriptions shown on the upper line and the output values on the lower line. The
output type selection is made using the SELECT keys on each side of the upper line;
simply press the key repeatedly until the required output type is shown. Note that it is
not possible to set both sides of the display to the same output type. Figure 4-9 makes
this clear.
The SELECT keys associated with the right-hand display also allow easy switching
of the display between an output expressed as a percentage of full-scale and the
corresponding output expressed in volts or amps using the “simultaneous double