Low-Noise Voltage Preamplifier (5113)

The model 5113 is a high performance, low noise voltage preamplifier with continuously adjustable gain and optional high, low or bandpass filtering. Its input can be configured for either single-ended or true differential operation with either DC or AC coupling, and its output will deliver up to 2 V peak to peak into a 50 Ω load.

All the principal instrument controls are operated via the three front-panel rotary knobs and a back-lit LCD display shows their present settings. The instrument also includes an optically isolated bi-directional RS232 interface allowing remote operation and interrogation of all controls. Since in some experiments even the very low levels of noise generated by the internal microprocessor that supports these capabilities may cause problems, the unit includes a "sleep" function whereby every source of digital noise is turned off after a predetermined interval. When in the sleep mode the unit "wakes up" as soon as any control is adjusted and goes back to sleep when adjustment is complete.

The unit can either be continuously line-powered from the supplied model PS0108 power supply, or be run from the internal rechargeable batteries which are charged whenever the power supply is connected. Battery operation often allows troublesome line frequency pick-up to be eliminated, as well as permitting operation away from a source of line power.

If the signal of interest is limited to a single frequency or narrow range of frequencies then the signal channel filters allow selective amplification of the signal, making subsequent signal measurement, for example on an oscilloscope or a lock-in amplifier, easier. The filters can be switched out of use to give a flat frequency response.

The model 5113 will find uses in applications as diverse as radio astronomy and audiometry or for independent use in test and measurement, process control and general purpose signal amplification and is ideally suited to work with our range of lock-in amplifiers.

Software support is available in the form of a LabVIEW driver supporting all instrument functions, and the Acquire™ data acquisition software. The driver and a demonstration version of the software, DemoAcquire, are available for download from this site.