HP 8902A Quick Reference Manual page 245

Operation
Model 8902A
COMMENTS
For
further details on Special Functions 49 and 50, refer t o Service Special Functions in SccVion 8 .
Internal Voltmeter Offset.
The RF power circuits d o not zero to OV. Instead they "zero" to between
0.W
and 0.8V which
permits the internal dc voltmeter
to
operate over its most linear range. The internal controller
subtracts this offset from subsequent power readings.
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