7443

FILTER Passive Audio bandpass Filter 7443 Series The 7443 series are passive bandpass filters which have been designed for safety critical applications. They are used in signalling, monitoring and supervisory systems where the information is carried by signals, typically in the audio frequency band. The filters are designed to operate over the range of temperature experienced in a non air-conditioned, unheated vehicle exposed to the temperature extremes found anywhere in North America. • The safety critical design feature provides that the output signal level falls by at least 18 dB below normal if any internal component becomes shorted or opens. • The filters are mounted in hermetically sealed steel cans. These provide a long life under adverse environmental conditions including high relative humidity. • The temperature stability is maximized by prolonged temperature cycling, prior to tuning, to reduce the disaccommodation factor of the ferrite core materials. In addition, capacitors are selected whose temperature coefficient of capacitance is the inverse of the temperature coefficient of inductance of the coils or transformers. • All filters tolerate 350 volts peak-to-peak at frequencies outside the pass band. • The filters are fitted with an octal plug to make the input and output connections. The filters have four 8-32 studs to provide secure mounting and withstand vibration. MECHANICAL (All dimensions in inches) ELECTRICAL SPECIFICATIONS @ 25˚C Center frequency range: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250 Hz to 10 kHz Bandwidth: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .± 30 Hz to ± 250 Hz Input level range: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.1 V to 3.5 Vrms Input Impedance: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .200 Ω Output Impedance: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2500 Ω Steepness factor: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 - 15 Steepness factor is defined as: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Bandwidth at 60 dB Bandwidth at 3 dB Voltage Insulation: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .750 VDC from input terminals to output terminals Operating temperature: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-20°C to +50°C Storage temperature: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-40°C to + 80°C Note: Other frequencies, bandwidths, impedances and other characteristics are available upon request. 7443 SERIES ISSUE: P1 23/10/02 229 Colonnade Road, Ottawa, Ontario, Canada K2E 7K3 Tel: (613) 226-1626 Fax: (613) 226-7124 www.filtran.com An ISO 9001 Registered Company