Article below is a part of the assembly process of the UHF duplexer – main article is HERE.
Drawing below shows a [AL100] – Coupling Loop Bar RX.
Main purpose of the part is to make a copper loop which engages the signal inside of the cavity. Loop is made of 1mm thick and 4mm wide copper.
Please note the TX coupling loops are slightly different, as they work as the notch capacitor!