Question T9B07
From subelement T9 - T9B
Which of the following is true of PL-259 type coax connectors?
Why is this correct?
PL-259 connectors are widely used at HF and VHF frequencies despite being called 'UHF connectors.' This name is misleading—they work well up to about 150 MHz but aren't ideal for true UHF frequencies above 400 MHz. They're not watertight, not bayonet-type (they screw on), and definitely not preferred for microwave operation where Type N connectors excel.
Memory tip
The 'UHF connector' name creates confusion—focus on actual frequency performance rather than the name. When you see frequency ranges in connector questions, think about which connectors handle higher frequencies better: PL-259 for HF/VHF, Type N for UHF and above.
Learn more
In practical amateur radio operation, PL-259/SO-239 pairs are the workhorse connectors for most HF and VHF equipment including mobile radios, base stations, and antenna tuners. Their robust construction handles high power levels well, making them standard on most amateur transceivers. However, their frequency limitations become apparent in UHF repeater work and microwave applications where precision impedance matching becomes critical for maintaining low VSWR and minimizing transmission line losses.
Think about it
Why do you think the PL-259 connector earned the nickname 'UHF connector' when it's not actually the best choice for UHF frequencies?