19
Operating the Probe
Recommended Test Equipment
Probe System Coupling Functions
dc Reject
dc Reject is the best method of eliminating the dc component of a signal when dc is not
a factor in the measurement.
The key characteristics are:
The low-frequency component (from dc to the selected corner frequency) is
automatically nulled by the dc reject circuitry.
Probe CMRR specifications are not compromised as happens when the ac coupling
adapter is uses.
There is a selectable low frequency corner with -3dB points at 0.05 Hz, 0.5 Hz,
or 5.0 Hz.
The voltage reject range is ±20 V with the probe alone, ±200 V with the 10x attenuator,
and ±500 V with the 100x attenuator.
dc offset dc Reject ac Coupling
Adapter
dc Blocked
Probe alone
Probe with 10x
Probe with 100x
± 20 V
± 200 V
± 500 V
± 20 V
± 200 V
± 500 V
± 20 V
± 500 V
± 500 V
Set-up needed Adjust offset to put
signal on screen
Select DC Reject
low-frequency
corner
Attach ac Coupling
adapter to
differential probe
Remote Control? Yes1Yes1No
CMRR
degradation?
No No Yes
Low-frequency
degradation?
No Yes Yes
1 Isolated external dc reference and control signals are needed