TiePie Handyscope HS4 DIFF-5MHz User Manual page 12

Figure 3.4: Differential attenuator matches with differential input
Standard oscilloscope probes and attenuators only attenuate one side of the sig-
nal path. These are not suitable to be used with a differential input. Using these
on a differential input will have a negative effect on the CMRR and will introduce
measurement errors.
The Differential Attenuator and the inputs of the Handyscope HS4 DIFF are
differential, which means that the outside of the BNC's are not grounded,
but carry life signals.
When using the attenuator, the following points have to be taken into considera-
tion:
•
do not connect other cables to the attenuator than the ones that are sup-
plied with the instrument
•
do not touch the metal parts of the BNC's when the attenuator is connected
to the circuit under test, they can carry a dangerous voltage. It will also in-
fluence the measurements and create measurement errors.
•
do not connect the outside of the two BNC's of the attenuator to each other
as this will short circuit a part of the internal circuit and will create measure-
ment errors
•
do not connect the outside of the BNC's of two or more attenuators that are
connected to different channels of the Handyscope HS4 DIFF to each other
8
Chapter 3
Figure 3.5: Standard probe is mismatch with differential input