RE: Testing HD Radio

DAB — Fri, 26 Jul 2013 18:56:10 GMT

Hi Gervasi,

I was not aware that they were introducing digital audio on AM and FM channels, but it makes sense.

The AM and FM bands remain among the last fully exploited frequencies for the modern digital age.

It would be interesting to compare the digital and analog broadcast to see if the digital encryption improves the music quality, especially in a moving vehicle where you can get more signal reflections and interference.

I agree, 20db does not sound like a lot of signal to noise support, but I suspect that it was limited by compatibility issues with the analog recievers.

I also suspect that other industries will begin to lobby for a redo of the channel allocation so that they can bring out new and improved broadcast content in these bands. It is probably just a matter of time.

Good post, I like how you keep the awareness up for RF.

Thanks

DAB

RE: Testing HD Radio

sqkybeaver — Fri, 26 Jul 2013 13:14:01 GMT

while digital portion is usually -20dB from the fm portion and uses less bandwidth than traditional fm, the digital signal just about doubles the total used bandwidth to 400KHz. I don't think that it is that efficent, It also means you can't have stations as close as fm-only stations could be(both in frequency and geographically)

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