Tektronix 540A Blood Glucose Meter User Manual


 
Vertical Control
Reference
Vertical Readout
Figure 3-79: Vertical Readouts and Channel Menu
Coupling
To choose the type of coupling for attaching the input signal to the vertical
attenuator for the selected channel and to set its input impedance:
Press VERTICAL MENU Coupling (main) DC, AC, GND, or (side).
DC coupling shows both the AC and DC components of an input signal.
AC coupling shows only the alternating components of an input signal.
Ground (GND) coupling disconnects the input signal from the acquisition.
Input impedance lets you select either 1 M or 50 impedance.
NOTE
If you select 50 impedance with AC coupling, the digitizing oscillo-
scope will not accurately display frequencies under 200 kHz.
Also, when you connect an active probe to the oscilloscope (such
as the P6205), the input impedance of the oscilloscope automatical-
ly becomes 50
. If you then connect a passive probe (like the
P6139A
),
you need to set the input impedance back to 1 M