Has anyone else noticed WBZ's unlistenable signal

Eli Polonsky elipolo@earthlink.net
Tue Jan 18 22:10:22 EST 2005

I don't know about the quadrature/phasing situation, but it appears to
me that if you listen to an IBOC AM station on an AM receiver with wide
enough bandwidth and higher than usual frequency response, the IBOC
noise is horrendous.

On the "wideband" AM stereo receivers manufactured in the 80's and 90's
the IBOC noise is quite loud even if listening in "wideband" mono. I've
also heard a lot of it on certain older AM mono radios that just happen
to have higher frequency response than today's.

The frequency response (for conventional analog broadcasts) of most of
today's newest digital tuning AM receivers seems more limited than ever,
the high end seems to be notched out above about 2K. Of course, they're
completely deaf to any IBOC hiss. They also all sound to me as if the
speakers are under pillows. I've seen late model car stereos where it
makes no difference on AM where you adjust the treble control, the
frequencies which the control affects are above the range that the AM
tuner is putting out!

On 1/18/05 8:18 PM, "Larry Weil" <kc1ih@mac.com> wrote:

> Yea, and you wonder how accurate the frequency is in a $9.95 digital
> walkman?

That can depend on how strong the batteries are. When the batteries
start to wear down in my Sony, the stations drift one digital notch
up on the dial. In other words, stations come in better tuned one
notch up the dial from where they should be, until I put new batteries
in it. Then they're back where they belong (or at least fairly close).

Eli Polonsky

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