450 MHz Band Pass Filter

Luigi IZ7PDX made this filter. It is a bandpass centered at 450 MHz that Luigi will use as an IF filter.

Luigi IZ7PDX’s centered bandpass filter at 450MHz front panel view.
The filter inside without the notch section activated (“parked” at 580 MHz).

Luigi characterized the filter using ADALM-PLUTO and SATSAGEN.

It’s the setup for the analysis of the filter. Note the attenuator placed on the RX side to improve impedance matching and preserve the RX stage of ADALM-PLUTO from possible damage.
The resulting response curve in a span of 200 MHz. The insertion loss is around 1.3 dB
It’s a scan performed with a 700MHz span.

Luigi has further improved the input and output impedance of the filter by acting on the coupling links and measuring with a vector antenna Analyzer:

It is scanning with a span of 200 MHz after improving the in/out impedance of the filter. The filter is “narrower” in terms of bandwidth than the previous scan before intervening on the coupling links.

Find Luigi IZ7PDX on:
- Youtube channel
- Site

One thought on “450 MHz Band Pass Filter”

  1. It is an excellent job, to take off your hat as we say here(para sacarse el sombrero), many congratulations, greetings from Peru.

Leave a Reply

Your email address will not be published. Required fields are marked *