OK, here's a question.
Let's say you have a 10kHz signal of a certain
amplitude within an electrical circuit.
I assume it is traveling at the speed of light minus
the velocity factor in copper.
Take that signal and connect it to a giant antenna.
It will radiate RF, not sound, right?
Take the identical signal and send it to a speaker.
It will radiate sound, not RF, right?
It's the same signal within the electrical circuit. Is
it possible when engineers are talking about radio
FREQUENCY or audio FREQUENCY, they are just talking
about a certain FREQUENCY, not whether it is sound or
RF? Can't the same signal be either sound OR RF?
Maybe they call the lower frequencies AF because they
are low enough to be CONSIDERED audio - because that
is the way they have traditionally been used. I think
possibly the new DSP situation renders the old
nomenclature of RF vs. AF obsolete.
--- RON ZOND <K3MIY@csonline.net> wrote:
> hi
>
> Regarding AF vs RF. Audio is heard by the ear, and
> consists of of
> compressions and rarefractions
> of air. RF (radio) is high frequency alternations of
> electric current, and
> is independent of the
> surrounding atmosphere. The frequency can be the
> same; you will hear AF and
> not RF, provided that
> the RF field is not strong, and does not shock
> excite any loose metal,
> example, horizontal oscillators in tv sets adversely
> affecting loose wires.
> The 14 kHz IF would only be detected by
> ear if a wire was loose and the fiels was strong,
> exremely unlkely with
> today's equipment.
>
> Ron
>
> -----Original Message-----
> From: tentec-bounces@contesting.com
> [mailto:tentec-bounces@contesting.com]On Behalf Of
> nq5t@attbi.com
> Sent: Monday, May 05, 2003 9:52 PM
> To: tentec@contesting.com
> Subject: Re: [TenTec] Hello Orion Users
>
>
> The relationship only exists because of the physical
> nature of how
> those two sensors on the sides of our head work.
> The distinction
> between audio and not-audio is irrelevant in this
> situation. As
> someone else pointed out, the difference has to do
> with definition of
> baseband frequency for the DSP IF. There's no
> relationship to what
> happens in the 14Khz IF system (pre-detection) to
> "audio" DSP.
>
> A dog can nearly hear a 50Khz IF signal, so
> following the "it's audio"
> logic, I guess we could say a drake 2-B has a linear
> "doggie audio"
> IF? :-)
>
> Grant/NQ5T
>
>
> > Well, I think you guys are both right.
> >
> > The DSP operates ahead of the audio stage, and
> thus can be called IF.
> >
> > Of course, the frequency of 14 khz is certainly in
> the audio range.
>
>
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