Motorola C-Quam AM Stereo custom built promo radio

[Negin]

Not when you're a Millennial luddite like me and only use a flip phone.

Same here. Classic stuff for me too!

 

[ContinuousWave]

Most AM rolls off well below 10kHz. If you can't hear frequencies above 5kHz, you seriously need a hearing checkup.

If your AM transmitter is rolling off well below 10k, you aren't much of an engineer...my AM using a DAX 3 is good to over 25k...so it's not the transmission..

The receivers, yes..they suck...and are the main issue of AM...modern design would include noise blanketing to get rid of the static/electrical, etc noise that is the main issue. The IFs are too tight..and the overall audio b/w rolls off externally as well.. modern DSP in HD radios could do the NB and variable audio bw to improve the quality..

Problem is getting the manfacturers to do it BUT a post by an engineer who talked was the one Japanese manufacturer rep said they WANT to hear from consumers as to what we want.. so maybe there is hope if enough people, especially broadcasters, do just that

 

[ZantennaG1]

modern DSP in HD radios could do the NB and variable audio bw to improve the quality..

My radio does have an adjustable bandwidth on AM, Shortwave, Longwave, and the Airband, and that ability is like a godsend to me. I'm not sure it has noise-blanketing like you discuss, however it is quite sufficient in reducing the overall noise in the atmosphere, at least compared to another one of my radios.

 

[boiseengineer]

If your AM transmitter is rolling off well below 10k, you aren't much of an engineer...my AM using a DAX 3 is good to over 25k...so it's not the transmission..

The receivers, yes..they suck...and are the main issue of AM...modern design would include noise blanketing to get rid of the static/electrical, etc noise that is the main issue. The IFs are too tight..and the overall audio b/w rolls off externally as well.. modern DSP in HD radios could do the NB and variable audio bw to improve the quality..

Problem is getting the manfacturers to do it BUT a post by an engineer who talked was the one Japanese manufacturer rep said they WANT to hear from consumers as to what we want.. so maybe there is hope if enough people, especially broadcasters, do just that

The old Clear Channel dictated that their AM's have a 5 KHz low pass filter on them.

 

[ContinuousWave]

The old Clear Channel dictated that their AM's have a 5 KHz low pass filter on them.

Yea know, I AM an old ex CC CE...NEVER saw that dictated...it's false ...the 5k was mandated only on stations running IBOC..non HD AMs still did 10k..

 

[davideduardo]

Yea know, I AM an old ex CC CE...NEVER saw that dictated...it's false ...the 5k was mandated only on stations running IBOC..non HD AMs still did 10k..

And a number of the CC AMs worked up to 6 k to 7 k audio bandwidth. From looking at the reports back then, they seem to have done that on the stations that were non-directional with broadened ATUs.

 

[kevtronics]

iHeartMedia (ex-Clear Channel)'s WOR in NYC is now using full 10 kHz audio bandwidth. WOR was one of the first stations to transmit AM IBOC, but they dropped it soon after Clear Channel took over.