[G0HZU_JMR]

This evening I made up a basic jig to test the XF-9 S43 LSB filter in and added the captap matching network. Then I tested it on the VNA.

I used smaller size toroids that have slightly lower Q for the inductors and I think this explains the 2.8dB insertion loss instead of the expected 2.5dB but it still looks good.

The metalwork in the jig needs optimising wrt screening to get low stopbands but the plot below is already showing promise. At present the jig has no screening lid and only a basic partition across the filter. So there is still some leakage.

I'll post up some more detailed VNA plots of the passband and return loss and group delay tomorrow.