Tighter AM iboc sidebands?

[Tom Wells]

I have no spectrum analyzer, but have filtered my statements through some time to see what this is.
The car radios of my preference use 262.5 IFs and have pretty steep cutoff skirt response, so when something like this
changes it's pretty easy to tune up and down a little and easily hear the new difference.

The stations still having older setups still have the same old bandwidth "Ponderosa" effect on the same radio.
They seem to have made a reduction in sideband-generated "secondary" images by 6-10 db.
As a result, there seems to be a bit more density in the host analog audio, without haing the sideband image response
reflecting back into the audio passband, and the same reduction in sidebands "beyond the sidebands" which
doesn't help the first adjacents at all, ( it might be even worse for firsts if all that energy is better focused now).
But it does clean things up for the second adjacents.

[Tom Wells]

More goings-on... Sat Dec 4  8 AM both stations were back to former "full skirts" bandwidths.
670's whoosh hitting the Espanol in Miwaukee on 640 and hissing even nigh unto the audio sidebands of WGN on 720!

There's not a chance in  H  E double toothpicks that WLW could be heard through it, so thats a huge difference suddenly.

780's whoosh reaching into the upper audio of WNDZ 750, and extending up to , and into the sidebands of whatever they
call 820 these days. 

Checking other adjacent responses WTMJ/WMT etc, found these all unchanged, so the radio's not crazy.

Slept all day so no idea what went on....

Then tonight Sat 10 PM on the way to work, they both seem back to be back in sharp and narrow mode.
There must some testing going on.  I really must dig out that Accurian tomorrow. Hope I can find the power supply
as I have been using it for various temporary functions. 

[KB1OKL]

More goings-on... Sat Dec 4  8 AM both stations were back to former "full skirts" bandwidths.
670's whoosh hitting the Espanol in Miwaukee on 640 and hissing even nigh unto the audio sidebands of WGN on 720!

There's not a chance in  H  E double toothpicks that WLW could be heard through it, so thats a huge difference suddenly.

780's whoosh reaching into the upper audio of WNDZ 750, and extending up to , and into the sidebands of whatever they
call 820 these days. 

Checking other adjacent responses WTMJ/WMT etc, found these all unchanged, so the radio's not crazy.

Slept all day so no idea what went on....

Then tonight Sat 10 PM on the way to work, they both seem back to be back in sharp and narrow mode.
There must some testing going on.  I really must dig out that Accurian tomorrow. Hope I can find the power supply
as I have been using it for various temporary functions. 

My local WTAG 580 has been off and on several times for week long periods lately but there very wide when on, luckily for MA there are off at night. I do know they tested the whoosh maker at night for several days and found it unworkable probably because of their wide sidebands, I heard somewhere they may have had antenna problems with the iBlock also.