1-1 PURPOSE The Model PAL-500, Power Amplifier, Linear, is a conservatively rated general purpose amplifier which provides 500 watts PEP output over the frequency range of 2 to 32 megacycles. 1-2 PHYSICAL DESCRIPTION The Model PAL-500 is composed of two small and compact units; the Linear Power Amplifier, Model RFE-1 (5!4 inch panel) and the Power Supply, Model PSP-500 (8¾ inch panel). The entire unit occupies only 14 inches of panel space for standard rack mounting which makes it ideal for console, table top, mobile, and shipboard installations. 1-3 FUNCTIONAL DESCRIPTION The combination of the TMC Model SBE, Mode Selector, Transmitting, and the PAL-500 provides a compact transmitting system capable of producing, single, double or independent sideband signals with any degree of carrier insertion. The PAL-500 has been carefully designed with no compromise in workmanship or component quality. A pair of 4CX350A Beam Power Amplifier tubes in parallel with a pi network provide unbalanced output from 50 to better than 600 ohms. Particular attention has been given to the suppression of distortion products, amplifier stability, power supply hum content and dynamic impedance. Full interlock, overload and fuse protection have been provided for the safety of the operating personnel and protection of the equipment. A filtered forced air blower system is included as an integral part of the equipment. An effective ALDC (Automatic Load and Drive Control) system has been included to limit the distortion produced when high drive peaks occur.