Operational amplifier based stretcher for stripline beam position monitors

A stretcher amp was designed to accommodate existing instrumentation at the Boeing free-electron laser (FEL) facility. The beam format for this system consists of two macropulses per second. In the stripline data acquisition system, one of six striplines is switched to a single transient digitizer channel. Tektronix TSS46 microwave relay switches are used. The output of the TSS46 goes into the stretcher amps described here. A Tektronix DSA602 digitizing signal analyzer was used to perform the linearity measurements. It was found that this oscilloscope had a nonlinear component to its response. In the method described, only output signals are observed by the oscilloscope. All six sets of data display a complex nonlinearity. It consists of an oscillation around the straight-line fit. It is clearly due to the DSA602. The data involving the DSA602 only are used to correct the data for the amplifiers. The result is then fitted with a linear-plus-quadratic function. The temperature dependence of gain and time delay were measured. Temperature effects and noise are discussed.<>