CP/PC364 Data Communications and Networks Laboratory

Frequency Shift Keying Pre-Lab

Datasheet: XR2206 [Copyright 1972 EXAR Corporation. Datasheet June 1997]

Using the XR-2206 datasheet determine the following and record in your lab notebook:

1. Find and sketch (or print and paste into your lab notebook) the circuit for sinusoidal FSK generation.

   Use the information in Table 1 and the datasheet to determine the values for the rest of the prelab.

   Table 1: Available Parts

   Power Supplies	Resistors (Ω)		Capacitors (μF)
   GND (0V)	10	1k	0.001	0.01
   +5V	3.9k	4.7k	0.033	0.047
   +12V	5.1k	10k	0.1	0.22
   -12V	20k	51k	0.33	0.47
   	100k	1M	1	10

2. Using the datasheet, select resistor values for R₁and R₂ in the mid range, then choose two different capacitor values from the list and determine the frequencies f₁ andf₂.
3. Using the datasheet, select a capacitor value in the mid range, then choose two different sets of resistor values for R₁and R₂ from the list and determine the frequencies f₁ andf₂.
4. Frequency Shift Keying Input
   • look up the information for the FSK input on the datasheet
   • what voltage levels are required for the keying input?
   • what hardware will you use for your keying input?
   • select a capacitor value, a resistor value to use for R₁ and a value for R₂.
   • draw your circuit
5. Determine the frequency of the output waveform for each of the two FSK input levels from Figure 13 in the datasheet.
   • Calculate and record the frequencies using the equations below.
   Frequency equations:
   f₁ = 1/(R₁C)
   f₂ = 1/(R₂C)
6. Write down all the parts you will need (chips, resistors, capacitors)