Testing The Red Led - Nellcor OxiMax SRC-MAX Technical Manual

Testing the RED LED

1. Turn on the signal generator.
2. Adjust the output until there is 475 to 525 millivolts peak
3. Connect one end of a 1 meg ohm resistor (R2 in Figure
4. Connect the other end to the positive terminal of the
5. Connect the negative terminal of the +5 volt supply to
Caution: See Figure 11. Prior to connecting the
oscilloscope's negative terminal to the +5 volt supply (+)
terminal, ensure that the oscilloscope negative is isolated
from the +5 volt supply ground.
6. Connect the oscilloscope channel 2 (+) lead to the
7. Connect the oscilloscope channel 2 (-) lead to the
8. With Low-Light setting selected on the SRC-MAX,
SRC-MAX
across the 10 ohm resistor.
11) to pin 9 of the 9 pin D-sub female connector.
power supply set for +5 volts.
pin 5 of the 9 pin D-sub female connector.
junction of pin 9 and the 1 meg ohm resistor.
junction of the positive terminal of the power supply (set
for +5 volts) and the other end of the 1 meg ohms.
measure the peak-to-peak voltage across the 1 meg ohm
resistor on channel 2 of the oscilloscope. the peak-to-
peak voltage should be 600 to 900 millivolts peak-to-
peak. See Figure 12. The peak-to-peak voltage tolerance
includes a possible probe impedance error.
Performance Verification
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