BEXT Inc.

1045 Tenth Avenue San Diego, CA 92101 USA (619) 239-8462 FAX (619) 239-8474

SF Series Low Pass Filter Optimization

See the diagram below for further details

1. Desolder center conductor of output cable from each RF amplifier.
2. Connect a 49.9 ohm, 1/4 watt resistor from center conductor to ground for each line. Make sure leads are extremely short.
3. Connect the sweep generator of the spectrum analyzer to the rear panel output jack of the SF unit. Set the sweep range for 50 - 150 MHz.
4. Connect the spectrum analyzer to the RF sample port on the front panel. Adjust the controls for a readout similar to that shown.
5. Adjust low pass filter tuning for as steep a slope as possible.

f_{1 115 MHz}

f_{2 160 MHz}

A_{1 -22 dB}

A_{2 0dB}