Performance Verification
16
SD-44 Instruction Manual
4. Set the optical impulse generator to the 1 MHz rate and low energy mode.
Adjust the optical attenuator so that the height of the impulse is about
200 mV
p-p
.
5. Set the digital sampling oscilloscope to 10 mV/div vertical scale, 100 ps/div
horizontal scale, 1024-point record length, and insure the entire impulse
waveform is within the display region. Shift the horizontal record so that the
start of the impulse is within the first two divisions of the horizontal scale on
the display.
6. Average the waveform a minimum of 256 times.
7. Store the averaged waveform.
8. Recall the stored waveform.
9. Using a controller attached to the scope via GPIB (i.e. a PC, MAC,
workstation, etc.) download the waveform.
10. Using the available controller software (i.e. Labview, etc) perform an FFT
(Fast Fourier Transform) on the waveform; this transforms the time-domain
(1024-point) impulse response to a scalar frequency response.
11. Check that the frequency response from DC to 15 GHz is greater than or
equal to –6 dB where dB = 20log (V
log
/V
dc
) or electrical power into 50
W
.