10368 MHz post coupled band pass filter for a 28 MHz IF
de N6CA July 2003
Tune for 10368 at lower edge of pass band. Approximately18 to 20 db return loss without matching screws.
Turns out you have to get the matching screws much further away from the posts than you do with iris type filters.
I made six of these and they are all pretty close.
10368 -1.6 db
10340 -22 db
10312 -35 db
BW3 approx 25 MHz
a cool way to pass DC straight through a waveguide band pass filter
-Drill and tap all holes, de-burr and clean & degrease.
-I used #2-56 stainless steel screws .312 length and they barely entered the cavities., split lock washers and small pattern nuts.
-Insert brass or Copper tubes, I used brass and Copper tubing, hard to find .344 Copper
-Clamp end plates with small wooden blocks and long adjustable clamp (furniture type)
-Solder end plates & tubing (both ends) with Propane torch
-Cut off excessive tubing, avoid breathing metal dust & paint when finishing.
-I use Acetone to clean off flux and cutting oil, it's cheap and you can get it most everywhere. but avoid skin contact.
73 de N6CA