It is important that the enclosure is made of non magnetic material. We use 2mm thick aluminium.The enclosures for all the 6 band pass filters are the same. You can make your own using the information below or buy a Hammond enclosure type 1411Z.
The way of grounding is very important. All pcb's and RF connections are grounded at the front side. So the front side is the single point of grounding. The RF connectors are mounted on the inside of the enclosure with the connection part sticking out! Between pcb 2/3 and 4/5 there is some extra space in order to mount a shielding between them. Have a close look at the pictures below for some details.