What Is A Lock-In Amplifier - Ametek 7280 Instruction Manual

Chapter 1, INTRODUCTION

1.2 What is a Lock-in Amplifier?

1-2
Appendix D
Shows the connection diagrams for suitable RS232 null-modem cables to couple the
unit to an IBM-PC or 100% compatible computer.
Appendix E
Provides a listing of the instrument settings produced by using the Auto-Default
functions.
Appendix F
Gives an alphabetical listing of the computer commands for easy reference.
New users are recommended to unpack the instrument and carry out the procedure in
chapter 2 to check that it is working satisfactorily. They should then make themselves
familiar with the information in chapters 3, 4 and 5, even if they intend that the unit
will eventually be used under computer control. Only when they are fully conversant
with operation from the front panel should they then turn to chapter 6 for information
on how to use the instrument remotely. Once the structure of the computer commands
is familiar, appendix F will prove convenient as it provides a complete alphabetical
listing of these commands in a single easy-to-use section.
In its most basic form the lock-in amplifier is an instrument with dual capability. It
can recover signals in the presence of an overwhelming noise background or
alternatively it can provide high resolution measurements of relatively clean signals
over several orders of magnitude and frequency.
Modern instruments, such as the model 7280, offer far more than these two basic
characteristics and it is this increased capability which has led to their acceptance in
many fields of scientific research, such as optics, electrochemistry, materials science,
fundamental physics and electrical engineering, as units which can provide the
optimum solution to a large range of measurement problems.
The model 7280 lock-in amplifier can function as a:-
AC Signal Recovery Instrument
Vector Voltmeter
Phase Meter
Spectrum Analyzer
These characteristics, all available in a single compact unit, make it an invaluable
addition to any laboratory.
Transient Recorder
Precision Oscillator
Frequency Meter
Noise Measurement Unit