70009 Parallax Inc, 70009 Datasheet - Page 65

• Manufacturer Part Number: 70009
• Description: BOOK UNDERSTANDING SIGNALS
• Manufacturer: Parallax Inc
• Type: Signal Analysisr

Specifications of 70009

• Style: Book
• Title: Understanding Signals
• Contents: Guide to Generate, View and Measure Wave Forms
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Other names: 70009PAR

If you are using the HomeWork Board, your calculation must account for the added
resistor value:
Again, your actual measurements may vary in accordance with the tolerances of the
resistor and capacitor you use.
ACTIVITY #2: VARIABLE RESISTORS IN AN RC NETWORK
In this activity we will measure the discharge time of an RC network and compare it to
the BASIC Stamp
(such as a photoresistor) with a known capacitor and resistor and measure it against the
OPTAscope to see how the two values compare.
Parts Required
(1) 220 Ω resistor
(1) 10 µF capacitor
(1) Photoresistor
(5) Jumper wires
Building the Photoresistor RC Network Circuit
Add a photoresistor to amend the circuit you previously built to match the schematic
(Figure 4-9) andwiring diagram (Figure 4-10). The 220 Ω resistor and 10 µF capacitor
will act as a filter for the
DEBUG
Time
Time
Time
FREQOUT
Time
Time
Constant
values. Then, we will calculate the value of a variable resistor
Constant
Constant
Constant
Constant
command to create a sine wave.
=
=
0.0122
=
(
0.01
220
=
=
1220
1000
seconds
+
seconds
1000
x
x
0.00001
0.00001
)
x
or
or
0.00001
10
12.2
ms
ms