Math - Db/Dbm Scaling - Keysight Truevolt Series Operating And Service Manual

Math - dB/dBm Scaling

This topic describes dB/dBm Scaling for the 34460A/61A. Scaling features are different
for the 34465A/70A and are described in the
The dB and dBm scaling functions, which apply to ACV and DCV measurements only, allow you to scale
measurements relative to a reference value.
Scaling is set to OFF when you change measurement functions (for example, changing from
DCV to ACV). You must re-enable scaling after changing measurement functions.
Front Panel Menus
The dB and dBm functions are accessed from the second softkey in the [Math] menu.
When the first softkey in the dB / dBm menu is enabled, as shown below, you will see one of the following
menus:
When function is dB:
When function is dBm:
dB Scaling
Each dB measurement is the difference between the input signal and a stored reference value, with both
values converted to dBm:
dB = reading in dBm – reference value in dBm
The relative value must be from -200 to +200 dBm (default 0). You can either measure this value by press-
ing Measure Ref Value , or you can enter a specified value.
Keysight True volt Series Operating and Service Guide
Features and Functions
Scaling topic.
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