Making New Artwork for 738 Interdigital Filter

One final mucking with Ansoft dimensions on the interdigital filter. I started by changing the microstrip impedance to 82 ohms (40 mils on this FR4 board). It was around 40 or 50 before from the initial Ansoft design. That appears to work much better. On the pipe cap filters the ideal impedance of the pipe coax structure was 77 ohms so that must hold in general for the micro strip filters too. The filter response is much better with the best return loss also being the center of the band pass response. The RL looks to be 15 or so. Insertion loss is still high but down under 15 DB now. Out of time for tonight so I will re-do the PC board artwork in Eagle tomorrow night.