Tektronix ADA400A Instruction Manual page 19

Reference
Connecting the Inputs
LN
Input Devices
Using the Proper Input
Leads
ADA4OOA Instruction Manual
COP <u
The Reference section describes how to connect the inputs of the ADA400A
Differential Preamplifier and make the proper control settings. To achieve the
best performance it is important to make the proper signal and ground connec-
tions, set the controls to optimize the performance of the preamplifier, and
reduce unwanted electrical interference.
Making the proper input connections is crucial to maintaining the fidelity of the
signal as well as eliminating unwanted noise. The characteristics of the signal
source and the type of measurement you wish to make, determine the type of
input leads you should use and the way you should connect the inputs.
WARNING. Do not attach the ADA400A Differential Preamplifier to human
subjects for any testing or bio-monitoring. The ADA400A Differential Preampli-
Jier is not safety certified for direct connection to humans.
The ADA4O0A Differential Preamplifier is able to amplify extremely small
signals that may or may not have a ground reference. Often the signals originate
from low-level, low-frequency transducers, and other similar sources of small
differential or floating voltages.
The inputs of the ADA400A Differential Preamplifier connect easily to devices
or leads that terminate with male BNC connectors. There are numerous adapters
readily available that can adapt other types of wire, cables, or plugs toa BNC
connector.
NOTE. Avoid using attenuating probes. The slightest difference in attenuation
match greatly lowers the common-mode rejection ratio.
To reduce unwanted electrical interference on the input leads, use shielded
coaxial cable or the recommended 1X probes to connect signals to the preampli-
fier inputs. The shielding in these types of leads intercepts and shunts electrical
noise to ground.