"Don Bowey" <dbowey@comcast.net> wrote in message
news:C2B403C2.6DC94%dbowey@comcast.net...
> On 7/4/07 8:42 PM, in article 468c6838$0$4664$4c368faf@roadrunner.com,
> "Ron
> Baker, Pluralitas!" <this@aint.me> wrote:
>
>>
>> "Don Bowey" <dbowey@comcast.net> wrote in message
>> news:C2B16AE5.6D5BC%dbowey@comcast.net...
>>> On 7/4/07 10:16 AM, in article 468bd5ad$0$16531$4c368faf@roadrunner.com,
>>> "Ron Baker, Pluralitas!" <this@aint.me> wrote:
>>>
>>>>
>>>> "Don Bowey" <dbowey@comcast.net> wrote in message
>>>> news:C2B1129D.6D573%dbowey@comcast.net...
>>>>> On 7/4/07 7:52 AM, in article
>>>>> 468bb3c0$0$24780$4c368faf@roadrunner.com,
>>>>> "Ron
>>>>> Baker, Pluralitas!" <this@aint.me> wrote:
>>>>
>>>> <snip>
>>>>
>>>>>>
>>>>>> cos(a) * cos(b) = 0.5 * (cos[a+b] + cos[a-b])
>>>>>>
>>>>>> Basically: multiplying two sine waves is
>>>>>> the same as adding the (half amplitude)
>>>>>> sum and difference frequencies.
>>>>>
>>>>> No, they aren't the same at all, they only appear to be the same
>>>>> before
>>>>> they are examined. The two sidebands will not have the correct phase
>>>>> relationship.
>>>>
>>>> What do you mean? What is the "correct"
>>>> relationship?
>>>>
>>>>>
>>>>> One could, temporarily, mistake the added combination for a full
>>>>> carrier
>>>>> with independent sidebands, however.
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>> (For sines it is
>>>>>> sin(a) * sin(b) = 0.5 * (cos[a-b]-cos[a+b])
>>>>>> = 0.5 * (sin[a-b+90degrees] - sin[a+b+90degrees])
>>>>>> = 0.5 * (sin[a-b+90degrees] + sin[a+b-90degrees])
>>>>>> )
>>>>>>
>>>>>> --
>>>>>> rb
>>>>>>
>>>>>
>>>>
>>>>
>>>
>>> When AM is correctly accomplished (a single voiceband signal is
>>> modulated
>>
>> The questions I posed were not about AM. The
>> subject could have been viewed as DSB but that
>> wasn't the specific intent either.
>
> You should take some time to more carefully frame your questions.
>
> Do you understand that a DSB signal *is* AM?

So all the AM broadcasters are wasting money by
generating a carrier?

>
> Post your intention; it might help.
>
>>
>>> onto a carrier via a non-linear process), at an envelope detector the
>>> two
>>> sidebands will be additive. But if you independe ntly place a carrier
>>> at
>>> frequency ( c ), another carrier at ( c-1 khz) and another carrier at
>>> (c+
>>> 1
>>> kHz), the composite can look like an AM signal, but it is not, and only
>>> by
>>> the most extreme luck will the sidebands be additive at the detector.
>>> They
>>> would probably cycle between additive and subtractive since they have no
>>> real relationship and were not the result of amplitude modulation.
>>>
>>
>>
>