The 5087A is a narrow-band amplifier capable of receiving up to four different input frequencies on three input channels. It amplifies these frequencies and supplies outputs in any selected combination on a total of 12 output lines. Each of the three input lines, as well as the 12 output lines and power supply voltage, may be monitored by a front-panel meter through a 16-position front-panel switch. All input and output connectors and fuses are on rear-panel.