Models 900CT & 900BT

8 Pole

Single Channel –

Certified

Low Pass Filters

6

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

Model

900L8B

900L8L

900L8E

900L8EY

Filter Specifications

Transfer Function

8-Pole

Butterworth

8-Pole

Bessel

8-Pole, 6 zero

Elliptic

8-Pole, 6 zero

Elliptic

Range fc, fr

0.1 Hz to 49.9 kHz

0.1 Hz to 49.9 kHz

0.1 Hz to 49.9 kHz

0.1 Hz to 49.9 kHz

Theoretical Transfer

Characteristics

Appendix A

Page 9

Appendix A

Page 4

Appendix A

Page 24

Appendix A

Page 25

Tuning Resolution

1 part in 499

within each decade

1 part in 499

within each decade

1 part in 499

within each decade

1 part in 499

within each decade

Passband Ripple

0.0 dB

0.0 dB

±0.035 dB

-0.05 dB

Pass Band Voltage

Gain

(non-inverting)

0

± 0.1 dB typ.

0

± 0.2 dB max.

0

± 0.1 dB typ.

0

± 0.2 dB max.

0

± 0.1 dB typ.

0

± 0.2 dB max.

0

± 0.1 dB typ.

0

± 0.2 dB max.

Stopband

Attenuation

48 dB/Octave

48 dB/Octave

-80 dB typ.

-100 dB typ.

Cutoff Frequency

fc

±2% max.

fc

±2% max.

fc

±2% max.

fc

±2% max.

Accuracy

±0.5% typ.

±2% max.

±0.5% typ.

±2% max.

±0.5% typ.

±2% max.

±0.5% typ.

±2% max.

Stability

±0.01%/°C typ.

±0.02%/°C max.

±0.01%/°C typ.

±0.02%/°C max.

±0.01%/°C typ.

±0.02%/°C max.

±0.01%/°C typ.

±0.02%/°C max.

Amplitude

-3 dB

-3 dB

-0.035 dB

-0.05 dB

Phase

-360

°

-182

°

-323

°

-419

°

Filter Attenuation

0.12 dB

0.80 fc

1.91 dB

0.80 fc

0.35 dB

1.00 fr

0.05 dB

1.00 fr

(theoretical)

3.01 dB

1.00 fc

3.01 dB

1.00 fc

3.01 dB

1.13 fr

3.01 dB

1.06 fr

60.0 dB

2.37 fc

60.0 dB

4.52 fc

60.0 dB

1.67 fr

60.0 dB

1.83 fr

80.0 dB

3.16 fc

80.0 dB

6.07 fc

80.0 dB

1.77 fr

80.0 dB

2.00 fr

Total Harmonic

Distortion @ 1 kHz

<-90 dB typ.

<-90 dB typ.

<-90 dB typ.

<-88 dB typ.

Wide Band Noise

(5 Hz – 2 MHz)

200

µV

200

µV

250

µV

250

µV

Narrow Band Noise

(5 Hz – 100 kHz)

50

µV

50

µV

75

µV

75

µV