Four Channel Oscilloscope:
The main GUI of ExpEYES17 resembles a four
channel oscilloscope, with additional elements for controlling the
function generator, voltage source etc. The screen shot below shows
data on three channels. Large number of activities can be performed using
the scope GUI, shown below.
A brief description of the oscilloscope program is given below.
The Oscilloscope program mainly functions as a four channel DSO to
view inputs A1, A2,A3 and MIC.
Adjust the x-axis limit of the graph, using the Timebase Slider,
generally to view several cycles of the waveform.
If the waveform is not stable, select the proper trigger source. If
needed adjust the Trigger level.
The traces can be saved to a file, in text format. It is possible
to take the Fourier transform and view the frequency spectrum of the
This scope program also has control/monitor widgets on the right
side panel to access most of the ExpEYES features.
The inputs A1, A2, A3 and the resistance connected to SEN are
measured and displayed every second. But these readings are
meaningless when AC inputs are connected.
For sinusoidal AC inputs, enable the Check-Button in front of the
channel widget to view the Peak voltage and frequency.
- The ExpEYES Input/Output terminals are
briefly described below.
- CCS: 1.1mA Constant Current Source. On/Off using
Check-Button Enable CCS.
- PV1: Progrmmable Voltage, +/5 volts range. Can be
set using the Slider or Text-Entry widget
- PV2: Similar to PV1, but ranges from -3.3V to +3.3V
- SQ1: Square Wave Generator, swings from 0 to 5V.
Frequency can be set from 1Hz to 5kHz
- SQ2: Same as SQ1, but available as an option of WG.
- OD1: Digital Output, voltage can be set to 0 or 5
- WG: Waveform Generator. Frequency from 1Hz to 5kHz.
Amplitude can be set to 3V, 1V or 80mV. Can be set to Sine, Triangular
or Square. In Square mode the output is on SQ2, with 0 to 5V swing.
- -WG: Inverted output of WG
- IN1: Input for measuring Capacitance. Push-Button
provided for measurement.
- IN2: Input for measuring frequency of digital
signals, swinging between 0 and (3 to 5) volts. Push-Button provided
- SEN: Input for measuring resistance. This point is
internally connected to 3.3 volts via a 5.1k resistor
- A1: Voltage measurement point, functions as
voltmeter and oscilloscope. Maximum Input range +/-16 volts, range is
selectable from pull down menu. AC/DC mode selection by slider switch
on the box.
- A2: Same as A1, but no AC coupled mode
- A3: Voltage measurement in +/-3.3 volt range. Small
signals can be amplified by connecting a resistance from Rg to Ground
- MIC: Condenser microphone input, output appears as
the fourth channel of the oscilloscope
- Rg: Gain resistor for A3. Gain = 1 + Rext/10000.
For example connecting a 1k resistor gives a gain of 11
The inputs A1, A2, A3 and the resistance connected to SEN are measured
and displayed every second. But these readings are meaningless when AC
inputs are connected. For sinusoidal AC inputs, enable the Check-Button
in front of the channel widget.