UHF BNC N Connector Return Loss Compared

Just a quick look at BNC-UHF, BNC-BNC, and BNC-N Adapter Return Loss at HF, VHF, and UHF to determine their suitability for use at Ham frequencies up to 1300 MHz.

Summary: 'UHF' connectors should be used below 150 MHz. BNC and N connectors are shown to be good up to the 1500 MHz limit of my Rigol DSA185-TG. By similarity we can assume that TNC, essentially a threaded version of a BNC, will have similar performance since it is still part of the 'NC' family of connectors.

Those paying close attention to the traces will notice why BNC connectors, though otherwise good at these frequencies, should probably only be used for test setups where quick connect/disconnect is required. During the video you will note that when i dropped the BNC connectors on the desk (3:16) and while I was handling the BNC adapter stack up (3:56) there was some obvious contact problems generating a spike in one case and contact noise in the other. That is why TNC connectors are used as a smaller diameter alternative to Type-N connectors in mobile applications instead of BNC connectors.

Comments and questions welcome.