EG&G 113 Low-Noise Preamplifier 300 kHz

The EG&G 113 Low-Noise Preamplifier 300 kHz provides high gain, low noise amplification of wideband signals from dc to 300 kHz. Adjustable high and low frequency roll-offs allow the bandwidth to be reduced. Two inputs, with individual coupling switches, allow either differential or single-ended operation. Calibrated gain is switch selectable from x10 to x10⁴ in a 1-2-5 sequence, and an uncalibrated gain vernier provides x1 to x2.5 range expansion. The unit may be powered either from the ac line or from its own batteries. The nickel-cadmium batteries recharge automatically during line operation. Other features include an overload fast-recovery switch, special circuitry that reduces the effects of ground-loop currents, front-panel dc zeroing and common mode rejection screwdriver controls and battery test provisions.