Bristol 428 - Page 16

Model 428 User’s Manual OPERATION
Bristol Instruments, Inc. 16
 Diff – Displays the difference between the start measurement and currently
displayed measurement values for each channel. The first column displays
the difference in wavelength, and the second column displays the difference
in power. The third column displays the channel number, current wavelength,
and current power of a chosen channel. Use the Arrow buttons to select a
channel, which is indicated by the tip of the dashed arrow.
1 0 . 0 1 2 4
- 1 . 1 2
1 : 0 0 : 0 0
2 0 . 0 2 3 7
- 1 . 2 3
R e s e t
3 0 . 0 1 3 4
- 0 . 6 6 3 o f 8
A v g : O f f
4 0 . 0 2 3 6
- 0 . 8 3 1 5 3 9 . 2 9 3 3
P o f f s : O f f
5 0 . 0 2 3 8
- 0 . 5 8 - 2 1 . 3 1
D r i f t
nm- v a c
d B m
D i f f
L i s t
M o d e


C h a n g e
S e l e c t
Figure 3.8: Drift – Diff
 Measurement Timer – Displays the time in hours, minutes, and seconds
that the instrument has been tracking channel values. The timer is reset
when the instrument is restarted, or can be manually restarted with the Reset
option.
 Reset – Restarts the tracking of channel values. Use the Select button to
highlight Reset, and use the Change button to reset the timer.
List Mode Display Screen – Delta
Displays the difference between each channel’s measured wavelength and a
chosen reference channel (Ref) or the wavelength of the nearest 100 GHz ITU
grid line (ITU). Use the Select button to highlight the Delta value, and use the
Change button to cycle through the Delta states.
 REF – Displays the difference in wavelength between each channel and the
reference channel (chosen in Config Screen 2). The first column displays the
difference in wavelength values, and the second column displays the current
power values. The third column displays the channel number, current
wavelength, and current power of a chosen channel. Use the Arrow buttons
to select a channel, which is indicated by the tip of the dashed arrow.
1 0 . 0 0 0 0
- 2 0 . 7 6
1 : 0 0 : 0 0
2 1 . 0 5 4 3
- 1 3 . 7 4
R e s e t
3 2 . 0 7 3 8
- 2 1 . 3 1 3 o f 8
A v g : O f f
4 3 . 0 1 6 3
- 1 3 . 3 3 1 5 3 1 . 5 8 7 8
P o f f s : O f f
5 4 . 0 1 3 3
- 9 . 4 2 - 2 1 . 3 1
D e l t a
nm- v a c
d B m
R e f : 1
L i s t
M o d e


C h a n g e
S e l e c t
Figure 3.9: Delta – REF