
8-Pole
Bessel
Low-Pass
Appendix A
4 
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Normalized Time (1/f sec)
S
Step Response
0
1
2
3
4
5
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
Normalized Time (1/f sec)
D
Delay 
(Normalized)
0.1
1.0
2
3
4
5 6 7 8 9
0.0
0.5
1.0
1.5
0.15
Normalized Frequency(f/fc)
A
Frequency Response
0.1
1.0
10.0
2
3 4 5 678
2
3 4 5 67
-100
-80
-60
-40
-20
0
(sec)
.506
.506
.506
.506
.506
.506
Theoretical Transfer Characteristics
1
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.85
0.90
0.95
1.00
1.10
1.20
1.30
1.40
1.50
1.60
1.70
1.80
1.90
2.00
2.25
2.50
2.75
3.00
3.25
3.50
4.00
5.00
6.00
7.00
8.00
9.00
10.0
1.
Normalized Group Delay:
   The above delay data is normalized to a corner frequency
   of 1.0Hz.The actual delay is the normalized delay divided
   by the actual corner frequency (fc).
Actual Delay  = 
Normalized Delay
Actual Corner Frequency (fc) in Hz
f/fc
(Hz)
Amp
(dB)
 0.00
-0.029
-0.117
-0.264
-0.470
-0.737
Phase
(deg)
 0.00
-18.2
-36.4
-54.7
-72.9
-91.1
Delay
-79.2
-89.8
-99.0
-107
-114
-33.4
-38.3
-43.1
-51.8
-66.8
-12.1
-13.7
-18.1
-23.1
-28.3
-6.10
-7.08
-8.16
-9.36
-10.7
-2.71
-3.01
-3.67
-4.40
-5.20
-1.06
-1.45
-1.91
-2.16
-2.42
-610
-626
-638
-647
-655
-489
-509
-526
-552
-587
-345
-362
-402
-436
-465
-255
-273
-291
-309
-327
-173
-182
-200
-219
-237
-109
-128
-146
-155
-164
.052
.038
.029
.023
.018
.241
.201
.170
.126
.077
.482
.468
.417
.352
.291
.505
.504
.502
.498
.492
.506
.506
.506
.506
.506
.506
.506
.506
.506
.506