Agilent Technologies 1660A Series User Reference page 52

Toggle Fields
Some fields will simply toggle between two options (like, On/Off). The
following example illustrates a toggle field in the Format menu.
Press the
1
Press the
2
then press the
The Polarity field toggles between positive (+) and negative (−) each time
you press the Select key. You can also toggle this particular field with the
front-panel ± key.
Polarity field
Polarity Toggle Field
MENU key.
Format
keys to highlight the Polarity field as shown below,
arrow
Select key.
Using the Front-Panel Interface
How to Select Fields
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