[BC] FM Stereo invention

[padrino]

It is the same. A/D sampling uses 50% duty cycle as well. BTW: There were
early A/D converters that worked on this exact same concept.

-Frank Foti

Broadcasters' Mailing List <broadcast at radiolists.net> writes:
>In a message dated 02/19/2007 2:34:02 PM Eastern Standard Time, 
>padrino at telos-systems.com writes:
>
>
>> What you're talking about is a simple sampling method. Not much
>different
>>  that what an A/D converter is doing at a base sampling rate. The
>theory is
>>  the same.
>>  
>>  -Frank Foti
>
>
>Not exactly, tho... in a true sampling environment, the signal level is 
>*held* until the next sample comes along. With the chopped 50/50 mpx, you
>have 
>alternating levels. With a stereo signal with a large variation between
>channels, 
>you'd have the level switching back and forth with a nearly 50% duty
>cycle. 
>If, let's say, the L channel was silent, then you'd have the R being
>chopped 
>on/off at that 50% duty cycle. It could be somewhat restored by a
>sample-and-hold 
>ckt in the receiver, but that's starting to get more complex than
>practical. 
>A low-pass filter would only tend to make the chopping less pronounced,
>but it 
>would still be there. Making the filter too aggressive would sharply 
>attenuate the highs.
>
>
>BTW, all- I'm just musing on this, I'm not really working on any
>projects, 
>studies, debates, or anything like that. I do appreciate the discussion!
>It's 
>very interesting! :)
>
>
>Willie...
>_______________________________________________
>
>
>The BROADCAST [BC] list is sponsored by SystemsStore On-Line Sales
>Cable-Connectors-Blocks-Racks-Wire Management-Test Gear-Tools and More! 
>www.SystemsStore.com       Tel: 407-656-3719    Sales at SystemsStore.com
>
>