drm

[thisistausif]

hello
does anyone hear about drm
what is it :?:
is its transmission is different from AM

 

[Styx]

its basically AM but in digital. So prolly one amplitude is a "1" and another is a "0" will give better noise ammunity then present AM, but why bother. AM is good because it is not that hard to modulate.

why not have DAB

 

[JohnBrown]

So prolly one amplitude is a "1" and another is a "0"

I think you'll find it's quite a bit more complicated than that!

 

[thisistausif]

its basically AM but in digital. So prolly one amplitude is a "1" and another is a "0" will give better noise ammunity then present AM, but why bother

what i hear that the quality of audio is much more better than our old AM.i am getting difficult to understand that :!: is this just using amplifier of computer and tunning digigtally or something else :?: and what is dab

 

[Styx]

DAB is "digital Audio Broadcasting" basically digital FM

DRM will be better than traditional AM as far a audible noise is concerned since they can set a wide hysteresis on the amplitude for what governs a "1" and what governs a "0". Then via some signal processing they can re-constuct the audio signal

 

[thisistausif]

does drm is transmitted diferentially than am

 

[Nigel Goodwin]

DAB is "digital Audio Broadcasting" basically digital FM

Except it's of inferior quality to FM, and only has limited coverage - yet another example of trying to force an inferior digital system on the public!.

There's been quite an outcry about the quality, they use too low a bitrate, resulting in lower quality than normal FM stereo.

If you want better quality digital audio you need to go to satellite, where there are many high quality digital radio channels (with higher bitrates than DAB).

 

[Styx]

I never said it was good.
I cant stand digital TV!! the slightest bit of noise on the signal and picture breaks up completely, yuo dont get that with analogue TV. a bit of snow but def watchable

 

[Styx]

does drm is transmitted diferentially than am

Bascally bosth are digital broadcasting over the airwaves.

As you know AM is "Amplitude Modulation" and FM is "Freqency modulation"

So basically for a DRM (Digi AM) say an amplitude of 10V is a "1" and a apmiltude of 5V is "0" (put a +/-2V hsyeresis around it and you have alot better noise amunity)


For DAB say a carrier of freq 500MHz and say a sideband at +200khz is a "1" and a sideband at +100kHz is a zero.

They are transmitted in exactly the same way it is the pre and post processing that differs