Agilent Technologies Infiniium 8000A Programmer's Reference Manual page 214

Query
Returned Format
Example
Channel Commands
PROBe:EXTernal:UNITs
:CHANnel<N>:PROBe:EXTernal:UNITs?
The :CHANnel<N>:PROBe:EXTernal:UNITs? query returns the current
external units setting for the probe on the specified channel.
[:CHANnel<N>:PROBe:EXTernal:UNITs] {VOLT | AMPere | WATT |
UNKNown}<NL>
This example places the external vertical units for the probe on the specified
channel in the string variable, Units$, then prints the contents of the variable
to the computer's screen.
10 DIM Units$[50]
20 OUTPUT 707;"CHANNEL1:PROBE:EXTERNAL ON"
30 OUTPUT 707;"CHANNEL1:PROBE:EXTERNAL:UNITS?"
40 ENTER 707;Units$
50 PRINT Units$
60 END
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