Velleman PCSU1000 RECORDER - Manual (Page 4)

Waveform Recorder Help 3
© 2005 ...Velleman
values switch CH1 off.
Coupling
AC: the input signal is capacitive coupled to the input amplifier/attenuator. Only the AC
components are measured.
GND: the input signal is broken and the input amplifier/attenuator is connected to earth. Use this
position for selecting a reference point on the display.
DC: the input signal is directly connected to the input amplifier/attenuator. Both AC and DC voltage
are measured.
Probe x1/x10
Use these buttons to adapt the readouts according to the x1/x10-probe setting.
Position
Position the traces vertically on the screen.
TIME/DIV
Selects the time setting for the beam to sweep one major division on the screen.
TIME/DIV (for zooming)
Selection of TIME/DIV is possible to zoom in on the frozen waveform display.
RUN
Selects recurrent display update mode (RUN). Pressing the button again freezes the display.
SINGLE
When button is depressed refreshment of the display takes place only once.
X-POSITION SCROLLBAR (Below the waveform display)
Positions the trace horizontally on the screen.
1.3 Troubleshooting
Errors in time scale
When recording at short timebase (< 2s/div) the sampling interval is 10ms. This is possible only on
fast computers. Anyhow, do not execute other applications during the recording process, it may
influence the measuring time scale.
The timebase of the measurements is generated by the internal timer of the computer. This timer can
be put on hold by other processes on the computer. This can cause a deviation in the time
measurement.
To ensure the precision of the time measurement at short timebase :
· Use a fast computer: Pentium.
· Do not run other applications when recording
· Use highest possible processor speed
· Prevent your computer from going into power saving mode
No signal
· No communication with the computer (check that the cable is connected to the USB port)
· If USB cable is connected, close the program. Disconnect and reconnect the USB cable and run
the Pc-Lab2000 program again.
· RUN button is not ON.
· The channel concerned is OFF.