Gentec-EO T-Rad (DB-15) - Manual (Page 11)

T-RAD-DB15--USB Instruction Manual Version 2.1 December. 2012 11
If we square these and add them together we obtain:
Now taking the square root gives:
The output of the multiplication is no longer phase dependent.
1.2.2
Time Domain Description of a Lock In Amplifier.
The input signal has peak amplitude of 5V (10V peak to peak) and a frequency of 25Hz and is
shown in figure 1.
Figure 1 Input Signal