Using The Pin Type CATV Connector
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These are the kinds of connectors that clamp to the outer shield and center conductor, have O-ring sealants, and have an extra long center pin. The outer thread is the same as the thread used on PL-259s and N jack connectors. What you want to do is cut the center pin on the hardline connector to the proper length to fit inside a N jack to N jack barrel adapter or just a coax jumper with a N jack. You can then use the cutoff outer shell of a PL-259 to secure the connection.
Overview of hardline connectors and adapters.
3/4 inch pin type hardline connector. Adapt using a double N jack adapter, or just use coax with a N jack.
3/4 inch compression type hardline connectors. Fit copper center conductor into a SO-239 to N plug adapter.