[BC] A bit disappointed.

[WFIFeng@aol.com]

In a message dated 01/15/2006 12:50:49 PM Eastern Standard Time, 
Robertm at broadcast.net writes:

> >dial accuracy at the top end.) The old FM radios could not be tweaked to 
> twice 
>  >their original frequency.
>  >  
>  >
>  
>  I think the frequency change had little to do with this. After the 
>  change you are still talking almost 30 years. FM evolved when it was 
>  forced to generate new content.

That makes a whole lot of sense... since I was quite young when this 
happened, my memories of it are somewhat vague. I do, however, remember "discovering" 
FM, and noticing the differences between it & AM. First of all, the music 
sounded a *whole* lot better, and was in stereo, too. The content certainly helped.


>  Sounds like you were thinking of DRE's system which I do think was at 
>  one point also called 'FM extra'.
>  Everything I have seen which include the NAB presentation looks good. 
>  Like everything else it takes real world field testing to flush out any 
>  possible bugs. IBOC is no different in this respect.

Yes, the DRE system is exactly what I was thinking of. So "simple", so 
inexpensive... yet it languishes in the shadow of the IBUZ HD Dominion.

>  Today you could do it [AM Stereo]
>  with DSP but that would not solve the problem that 
>  it can't pass through a real world receiver properly. Look at it this 
(snip)
>  Generating ISB requires the Hilbert transform. This only works in the 
>  DSP world, any analog implementation has a negative impact on processed 
>  audio. In either case it is another block in the path that other systems 
>  do not have. There is no question that Magnavox was the simplest system 
>  and it did work. Just bad political savvy on the part of those promoting 
>  the system to broadcasters.

Ok, that makes sense... since AM Stereo is pretty much dead, anyway, not much 
use in going into that.

>  >How many could truly be relied upon, though, to "do the right things"?
>  >  
> 
>  even if you didn't it was not a big deal. More like how you wanted your 
>  station to sound on a typical radio. This is more like tuning an FM 
>  station for minimum synchronous AM.

Ok, sounds pretty "simple", then.
  
>  >Somebody majorly goofed on that one! <:(
>  >
>  >  
>  >
>  Not really, it is just a reality.  If you processed for a typical radio 
>  and then listened on a wide band radio it was unlistenable. We all hear 
>  this every time you listen off a mod monitor.

Not if the Mod Mon was properly de-emphasized, as ours is for the AM NRSC 
curve.

>  The old content thing is one reason. Turns out L band receivers don't 
>  hear all that well and the system was never full implemented, primarily 
>  due to the first two reasons.

Fully understandable.

>  That TV channel thing will never fly. 

Sadly, this appears to be true. It would be the *simplest* solution, though.

> The AM problem can be solved in 
>  band but with lowered but still satisfactory expectations.

Lowered how far, though? Certainly not to the point of planting white-noise 
generators on either side of every station?

>  You are still thinking old school traditional radio. Aim higher.

HUH? Now I'm completely lost.

Willie...