HP 83487A, User Manual, Page: 33 / 98

2-11
Channel Setup Menu
External scale....
Units
The
Units
function lets you select the unit of measure appended to the channel
scale, offset, trigger level, and vertical measurement values. For the optical
channel these units are Volts or Watts. For the electrical channel the units are
Volts, Amperes, Watts, or unknown. Use Volt for voltage probes, Ampere for
current probes, Watt for optical-to-electrical (O/E) converters, and unknown
when there is no unit of measure or when the unit of measure is not one of the
available choices.
Key Path
Channel, External scale
....
, Units
Ext gain
and
Ext offset
When you select Ampere, Watt, or unknown on an electrical channel or Volt-
age on an optical channel, two additional functions become available: External
Gain and External Offset. These two additional functions allow you to com-
pensate for the actual characteristics of the probe rather than the ideal char-
acteristics. For example, you might have an amplified lightwave converter
with ideal characteristics of 300 V/W with 0 V offset, but actual characteristics
of 324 V/W with 1 mV of output offset. In this case you would set the External
Gain to 324 V/W and the External Offset to 1 mV.
Key Path
Channel, External scale
....
, Units
,
Volt
,
Ext gain
or
Ext offset
Channel , External scale
....
, Units
,
Watt
,
Ext gain
or
Ext offset
Channel
,
External scale
....
, Units
,
Unknown
,
Ext gain
or
Ext offset