TFS285

      The TFS285 is designed as VI telefilter.
      Reference level for the relative attenuation arel of the TFS 285 is the minimum of the pass band attenuation amin. The minimum of the pass band attenuation amin is defined as the insertion loss ae. The centre frequency fo is the arithmetic mean value of the upper and lower frequencies at the 30 dB filter attenuation level relative to the insertion loss ae. The nominal frequency fN is fixed on 285 MHz without tolerance. The given values for the relative attenuation arel and for the group delay ripple have to be reached at the frequencies given below also if the centre frequency fo is shifted due to the temperature coefficient of frequency TCf in the operating temperature range and due to a production tolerance for the centre frequency fo.
      Some important specifications of TFS285 have been concluded into several points as follow. The first one is about its insertion loss which would be typ 9,5 dB and max. 12 dB (Reference level). The next one is about its nominal frequency which would be max 285 MHz. The next one is about its pass band ripple at fN ± 7,5 MHz which would be typ 0,8 dB and max. 1,2 dB. The next one is about its passband width at 3 dB which would be min. 20 MHz. The next one is about its group delay ripple at fN ± 7,5 MHz which would be typ 90 ns and max. 150 ns. The next one is about its relative attenuation which would be typ 38dB and min 30dB from fN - 75 MHz to fN - 20 MHz and would be typ 38dB and max 30dB from fN + 20 MHz to fN + 75 MHz. The next one is about its VSWR ratio at fN 7,5 MHz ... fN + 7,5 MHz which would be max. 2 : 1. The next one is about its operating temperature range which would be from - 5 °C to + 85 °C. The next one is about its temperature coefficient of frequency which would be typ - 72 ppm/K. The next one is about its input power level which would be max. + 10 dBm. And so on. For more information please contact us.