The RM KL-405 is a 13.8V linear amplifier designed primarily for the 10m amateur band, with extended HF coverage from 1.8–30MHz when used with a suitable low-pass filter. It delivers up to 180W output from 1–10W of drive across all modes, and features a six-position output power selector on the front panel for precise power control. A built-in 25dB RX preamplifier with electronic switching is activated via a front panel switch. The KL-405 is the naturally cooled version of the KL-405 range. For the fan-cooled variant suited to sustained high-power operation, see the RM KL-405V. Note: Always ensure your antenna system is correctly matched (SWR within specification) before using a linear amplifier. Check local regulations regarding the use of linear amplifiers on amateur and CB frequencies. Key Features Frequency: 10m amateur band (1.8–30MHz with LPF) Output power: 180W max Input power: 1–10W (all modes) Six-position output power selector (front panel) Built-in 25dB RX preamplifier (switchable via front panel) Natural convection cooling (no fan) Power supply: 13.8V DC ±1V, 30A Input current: 22A max Fuse: 3 × 12A fast (5×20mm)