New Year, New Band Pass Filter

I wanted to use my new rtl-sdr I got for Christmas on the 40m band (using my dipole).  But I was worried about what noise I might get in there, so I decided I'd make a band pass filter.  I used this design from ARRL.  I put it in a little hexagon box some sort of soap came in.  Possibly not the best idea - it was kind of hard to get the BNC connections is, but it worked out.  I measured it with the nanoVNA, and it looked like a band pass filter, so that is good.  I'm not sure I've calibrated anything else, as it looks like there is a lot of insertion loss that I don't really think is there.  Will need to look into that.