From: Jim Thompson
Subject: Re: How does a mixer work?
References: <firstname.lastname@example.org> <2ltr9.338$cV6.email@example.com> <3DAED797.firstname.lastname@example.org> <3DAEDE54.email@example.com>
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Date: Thu, 17 Oct 2002 16:12:02 GMT
NNTP-Posting-Date: Thu, 17 Oct 2002 12:12:02 EDT
Organization: Cox Communications
On Thu, 17 Oct 2002 15:59:24 GMT,
Fred Bloggs ,
In Newsgroup: sci.electronics.design,
Entitled: "Re: How does a mixer work?",
Wrote the following:
|Kevin Aylward wrote:
|> "Fred Bloggs" wrote in message
|>>Kevin Aylward wrote:
|>>>The basic reason is based on a standard trigonometric result.
|>>>Sin(A)*Sin(B)= 0.5*(Cos(A-B) + cos(A+B))
|>>Huh? And which alternative reality is this?
|> This one. In what universe is this not true?
|Seriously , Kevin, cos(A+B)=cos(A)cos(B)-sin(A)sin(B). If it's any
| I like your explanation the best.
(1) cos(A+B) = cos(A)cos(B)-sin(A)sin(B)
(2) cos(A-B) = cos(A)cos(B)+sin(A)sin(B)
(2)-(1)-> cos(A-B)-cos(A+B) = 2*sin(A)sin(B)
or sin(A)sin(B) = 0.5*(cos(A-B)-cos(A+B))
so Kevin has a sign error ;-)
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| Jim-T@analog_innovations.com Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
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I love to cook with wine. Sometimes I even put it in the food.