catalog index

diode laser spectroscopy

earth's field nmr

earth's field nmr gradient/field coil system

fabry-perot cavity

faraday rotation

hall effect

magnetic force

magnetic torque

magnetic torque's magnetic force balance

modern interferometry

muon physics

noise fundamentals

optical pumping

power/audio amplifier

pulsed/cw nmr

pulsed nmr

quantum analogs

signal processor
/lock-in amplifier

sonoluminescence

torsional oscillator

two slit interference, one photon at a time

two slit's cricket

individual parts

Newsletter – Signal Processor/Lock Amplifier - Our Utility Infielder
Learn about Faraday Rotation (FR1-A)
Learn about Power Audio Amplifer PAA1-A

Signal Processor/Lock-In Amplifier Brochure

The Instrument



Understanding Extraction of Signal from Noise

The unique design of TeachSpin's Signal Processor/Lock-In amplifier, SPLIA1-A, makes it particularly appropriate for teaching. Nothing is automated!

The modular layout electrically and spatially separates the preamplifier, filter, amplitude and lock-in detectors, low-pass amplifier, phase shifter, reference oscillator, noise generator, and attenuator. All of the interconnections between the modules must be made by the operator using short BNC cables provided with the apparatus. Students easily configure these individual modules in a variety of ways to explore various "strategies" for enhancing the signal-to-noise of weak signals.

In addition, students must manually adjust all the controls on the SPLIA1-A. With this signal processor, students are required to set the appropriate gain levels on various modules and to monitor the signal as it progresses through the instrument. An interesting set of experiments has students examine the signal-to-noise ratio of a particular signal first using the instrument in its amplitude detection (precision rectifier) mode and then using the instrument as a lock-in amplifier. For the same signal they can toggle between these two systems and begin to appreciate the real power of a lock-in amplifier.

Students can explore the basics of signal processing by using a variety of techniques to "massage" known signals from a built-in signal generator. They can set their own challenges by varying the accompanying "noise" with the built-in noise generator.

And with the confidence gained manipulating known signals, they can then use this instrument which has become "theirs" to wrest signal from noise in a wide variety situations.

introduction | the instrument | experiments | specifications| prices