Connectors - UHF

UHF Connectors - Commonly referred to as a UHF (Male or Female), PL-259 and SO-239.  The UHF connector dates back to the 1930s and is largely a standard on HF and other radios. Useful at HF without much issue, many radios in the VHF and UHF frequency ranges come standard with UHF connectors and the connector is not really a top performer at VHF and above frequencies. Not that one would probably notice the difference talking to a buddy across town, but measurements indicate it is better at HF than VHF or UHF.  You will likely heat the cable before you ruin a good connector with RF power.

Important — Standard 5/8"-24 vs. Metric UHF-Style Threads

Unless specifically stated otherwise in an individual product description, the UHF connectors offered here use the standard PL-259/SO-239 5/8"-24 UNEF interface.

Some China-made and other imported UHF-style connectors use a metric thread instead of the standard 5/8"-24 UNEF thread. A commonly encountered version is M16×1, having a nominal 16 mm diameter and 1 mm thread pitch. Variations also exist among imported connectors, so appearance alone is not a reliable way to determine the thread specification.

These connectors can look very similar to standard PL-259/SO-239 connectors, but they should not be assumed to be interchangeable. Attempting to mate mismatched threads can result in poor fit, damaged or stripped threads, and an unreliable mechanical or RF connection.

An additional source of confusion is that some CB radios, radios, antenna mounts, and other equipment may themselves use the metric-style interface. A connector threading onto one of these devices successfully does not necessarily prove that it has the standard 5/8"-24 UHF thread.

If there is any doubt, verify the thread specification with the equipment or connector manufacturer, or measure the connector using an appropriate thread gauge or caliper. Do not force a connector that does not thread smoothly.

Unless specifically noted otherwise, W5SWL UHF adapters in this collection use the standard 5/8"-24 PL-259/SO-239 thread specification.

For additional information about identifying these two thread types, see our FAQ:

A Normal PL-259/SO-239 Thread vs. the China-Made PL-259 Thread

HEX Crimp Die Sizes* for FERRULES for common RF Cables: