This document establishes official Palomar Engineers guidelines for selecting and derating feed line chokes, baluns, and ununs based on SWR, duty cycle, and operating mode. It enables customers to match their operating conditions with the appropriate product power (100 W, 500 W, 1500 W, 3000W, or 5000 W PEP) and mode (SSB, CW, AM/FM, RTTY/FT4, FT8, Continuous Carrier) and expected load SWR for reliable, long-term service. Second Edition Updated 03/26/2026 - Bigger and Better with more info you can use!