The RM Italy KL-503 is a 300W linear amplifier for the 25–30 MHz band — covering the full CB band (27 MHz) and the 10m amateur band (28–30 MHz). Designed for mobile or base station use from a 12V supply, it accepts 1–6W of drive power across all modes (AM, FM, SSB, CW), making it well suited to standard CB and 10m transceivers operating at typical output levels.A six-position power selector on the front panel allows output power to be adjusted to suit operating conditions or licence requirements. An RX preamplifier with electronic switching — activated via a front panel switch — boosts received signal sensitivity when needed. Made in Italy.Note: The KL-503 HD variant accepts up to 35W of drive power — choose the HD if your transceiver outputs more than 6W.Key Features Frequency: 25–30 MHz (CB band & 10m amateur) Output power: 300W Input power: 1–6W (all modes) Modes: AM, FM, SSB, CW 6-position power selector (front panel) RX preamplifier with electronic switching Power supply: 13.8V DC ±1V, 40A Max input current: 30A Fuse: 3 × 10A fast blow (5×20mm) Dimensions: 300 × 190 × 67mm Made in Italy Technical Specifications Frequency: 25–30 MHz Output power: 300W Input power: 1–6W Modes: AM, FM, SSB, CW Power supply: 13.8V DC ±1V, 40A Input current: 30A max Input VSWR: 1.1–1.5:1 Fuse: 3 × 10A fast (5×20mm) Dimensions: 300 × 190 × 67mm
