8-Pole
Bessel
Appendix A
Low-Pass
Theoretical Transfer Characteristics
1
Frequency Response
0
-20
-40
-60
-80
-100
f/fc
Amp
(dB)
Phase
(deg)
Delay
(sec)
(Hz)
0.00
0.10
0.20
0.30
0.40
0.50
0.00
0.00
-18.2
-36.4
-54.7
-72.9
-91.1
.506
.506
.506
.506
.506
.506
-0.029
-0.117
-0.264
-0.470
-0.737
0.60
0.70
0.80
0.85
0.90
-1.06
-1.45
-1.91
-2.16
-2.42
-109
-128
-146
-155
-164
.506
.506
.506
.506
.506
2
2
3 4 5 6 7
0.1
3 4 5 6 781.0
10.0
Normalized Frequency(f/fc)
0.95
1.00
1.10
1.20
1.30
-2.71
-3.01
-3.67
-4.40
-5.20
-173
-182
-200
-219
-237
.506
.506
.506
.506
.506
Delay (Normalized)
1.0
0.5
0.0
1.40
1.50
1.60
1.70
1.80
-6.10
-7.08
-8.16
-9.36
-10.7
-255
-273
-291
-309
-327
.505
.504
.502
.498
.492
1.90
2.00
2.25
2.50
2.75
-12.1
-13.7
-18.1
-23.1
-28.3
-345
-362
-402
-436
-465
.482
.468
.417
.352
.291
0.15 2
3
4
5 6 7 8 9
1.5
0.1
1.0
3.00
3.25
3.50
4.00
5.00
-33.4
-38.3
-43.1
-51.8
-66.8
-489
-509
-526
-552
-587
.241
.201
.170
.126
.077
Normalized Time (1/f sec)
Step Response
1.2
1.0
0.8
0.6
0.4
0.2
6.00
7.00
8.00
9.00
10.0
-79.2
-89.8
-99.0
-107
-114
-610
-626
-638
-647
-655
.052
.038
.029
.023
.018
-0.0
-0.2
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).
0
1
2
3
4
5
Normalized Time (1/f sec)
Normalized Delay
Actual Delay =
Actual Corner Frequency (fc) in Hz
7
1784 Chessie Lane, Ottawa, IL 61350 • Tel: 800/252-7074, 815/434-7800 • FAX: 815/434-8176
e-mail: sales@freqdev.com Web Address: http://www.freqdev.com
FREQUENCYDEVICES [ FREQUENCY DEVICES, INC. ]
