No, not exactly. Addition is a linear process and produces no frequencies in the output of the summation which are not present in the input. A nonlinear process is commonly applied to the summation to create beats. For example putting a summation of sine wave voltages onto a diode would produce a nonlinear current that would contain the beats.
Sampling, like multiplication, is also a nonlinear process that can produce beats. On Sun, Oct 18, 2020 at 12:19 PM H LV <hveeder...@gmail.com> wrote: > So the addition of frequencies requires that the input signal already > contains a non-linear component. > and for entirely linear input the frequencies would not be additive. > Harry > > On Sun, Oct 18, 2020 at 12:08 PM Bob Higgins <rj.bob.higg...@gmail.com> > wrote: > >> To get frequencies in the output that were not in the input requires a >> nonlinearity. If you model the nonlinearity using a series such as Y = a + >> bX + cX^2 + dX^3... >> then all of the terms with X^2 and greater are the nonlinear terms. >> Usually the coefficient of the squared term, c, is the largest of the >> nonlinear terms. When you have an input that is the sum of two >> frequencies, you get a component in Y that is c[sin(w1t) + sin(w2t)]^2 . >> It is the square of the sum of sines that produces the sum and difference >> frequencies. >> >> In the case of the Moire masks, you end up with a multiplication taking >> place, not a sum. The product of sines will also produce a sum and >> difference. Multiplication of inputs is a nonlinear operation. >> >> On Sun, Oct 18, 2020 at 9:44 AM H LV <hveeder...@gmail.com> wrote: >> >>> Hi, >>> When two waves of different frequencies combine the result is a third >>> wave with a beat frequency corresponding to the difference between the two >>> original frequencies. A wave model can show how this happens, but I don't >>> see how it can bring about the addition of frequencies. Can someone model >>> this additive process for me? >>> >>> Harry >>> >>>>
