WTF is the transform for a sinc function times a cosine?

I'm trying to go to H(jW), from h(t) = 2*sin(2*pi*t)/(pi*t) * cos(7*pi*t), and I keep getting FUBAR answers.

(I suspect I'm missing something very obvious here.)

11/9/2006 1:29:00 AM

Hmph.

[Edited on November 9, 2006 at 6:46 AM. Reason : .]

11/9/2006 6:26:23 AM

You know that multiplication in the time domain is convolution in the frequency domain. What is the convolution of the frequency domain representation of the sinc and the frequency domain representation of the cosine?

11/9/2006 7:38:50 AM

nevermind. that wasn't right.

[Edited on November 9, 2006 at 7:49 AM. Reason : ]

11/9/2006 7:47:24 AM

U(W - 5*PI) - U(W + 5PI) + U(W + 9*PI) - U(W - 9*PI)

U == Heaviside (STEP) function

[Edited on November 9, 2006 at 6:23 PM. Reason : ]

11/9/2006 6:22:18 PM