Is my analogue tuner *digital*..??
 

"tony sayer" wrote in message
...
In article , Keith G
scribeth thus

I don't mind admitting that most of the information on this page:

http://www.apah69.dsl.pipex.com/show/Tuner.JPG

flies right over my head, but it's all very interesting! What is
paragraph 5 saying - that my *analogue* tuner is carrying out A/D and
D/A conversions..??




Its digital Keith .. but not as we know it;)...


It's the words 'digital circuits' and the square waveforms in the piccy
wot dun it....

Is my analogue tuner *digital*..??
 

"Keith G" wrote in message
...

I don't mind admitting that most of the information on this page:

http://www.apah69.dsl.pipex.com/show/Tuner.JPG

flies right over my head, but it's all very interesting! What is paragraph
5 saying - that my *analogue* tuner is carrying out A/D and D/A
conversions..??

No, it is stopping well short of that.

A truly digital FM tuner would digitize the inbound signal fairly close to
the antenna terminals, and use FFT-based processing to select stations and
decode the Stereo multiplex signals.

Is my analogue tuner *digital*..??
 

"Arny Krueger" wrote in message
. ..

"Keith G" wrote in message
...

I don't mind admitting that most of the information on this page:

http://www.apah69.dsl.pipex.com/show/Tuner.JPG

flies right over my head, but it's all very interesting! What is
paragraph 5 saying - that my *analogue* tuner is carrying out A/D and
D/A conversions..??

No, it is stopping well short of that.

A truly digital FM tuner would digitize the inbound signal fairly
close to the antenna terminals, and use FFT-based processing to select
stations and decode the Stereo multiplex signals.


OK....

Is my analogue tuner *digital*..??
 

On Thu, 23 Aug 2007 11:45:30 +0100, "Keith G"
wrote:


"Don Pearce" wrote in message
...
On Thu, 23 Aug 2007 03:05:30 +0100, "Keith G"
wrote:


I don't mind admitting that most of the information on this page:

http://www.apah69.dsl.pipex.com/show/Tuner.JPG

flies right over my head, but it's all very interesting! What is
paragraph 5 saying - that my *analogue* tuner is carrying out A/D and
D/A conversions..??



No. It is making the audio output the same way a class D amplifier
does. It generates pulses of constant width and measures their average
level. When the frequency is higher, they are closer together and the
average level goes up. When the frequency is lower they are further
apart and the level goes down. That gives you your audio from the
frequency modulation.


OK, like in the diagram:

http://www.apah69.dsl.pipex.com/show/Brochure01.JPG

Which I see as:

1) Wiggly line
2) Chunks
3) More chunks
4) Even more chunks
5) Wiggly line again...

You know what my next question would be, don't you? :-)

(The words 'modem', 'analogue signal' and 'why bother' would figure in
it, I suspect...)



Would you mind awfully if we didn't go there? ;-)

d

--
Pearce Consulting
http://www.pearce.uk.com

Is my analogue tuner *digital*..??
 

"Don Pearce" wrote in message
...
On Thu, 23 Aug 2007 11:45:30 +0100, "Keith G"
wrote:


"Don Pearce" wrote in message
...
On Thu, 23 Aug 2007 03:05:30 +0100, "Keith G"

wrote:


I don't mind admitting that most of the information on this page:

http://www.apah69.dsl.pipex.com/show/Tuner.JPG

flies right over my head, but it's all very interesting! What is
paragraph 5 saying - that my *analogue* tuner is carrying out A/D
and
D/A conversions..??



No. It is making the audio output the same way a class D amplifier
does. It generates pulses of constant width and measures their
average
level. When the frequency is higher, they are closer together and
the
average level goes up. When the frequency is lower they are further
apart and the level goes down. That gives you your audio from the
frequency modulation.


OK, like in the diagram:

http://www.apah69.dsl.pipex.com/show/Brochure01.JPG

Which I see as:

1) Wiggly line
2) Chunks
3) More chunks
4) Even more chunks
5) Wiggly line again...

You know what my next question would be, don't you? :-)

(The words 'modem', 'analogue signal' and 'why bother' would figure in
it, I suspect...)



Would you mind awfully if we didn't go there? ;-)


Not in the *least*!! :-)