[BC] Real cases of IBOC interference wanted for research purposes

[Mark Durenberger]

Good stuff David.  As long as we're at it, try this URL as well.

http://www.durenberger.com/iboc%20observations.mp3

Should be self-explanatory.  This is a snip from a monthly audio column for 
the Blind.  Audio is taken on a Minidisk from a 2010 receiver connected to a 
Beverage antenna located in the Eastern Utah desert.  The 2010 has 4 khz 
I.F. filters and is operating in 'normal' wideband mode (both sidebands). 
Each audio snip is recorded just before stations drop their IBOC carriers at 
local sunset.

Mark Durenberger


----- Original Message ----- 
From: "David L. Hershberger" <dave at w9gr.com>
To: "Broadcasters' Mailing List" <broadcast at radiolists.net>
Sent: Monday, July 24, 2006 10:58 AM
Subject: Re: [BC] Real cases of IBOC interference wanted for research 
purposes


> Hi Doug and colleagues,
>
> Last Thursday night (July 20) I made a MP3 recording of another local IBOC
> interference situation and posted the file here:
>
> http://www.w9gr.com/KKOH-KCBC-IBOC.mp3
>
> This recording was made in the few minutes spanning pattern change/power
> change (8:30 PM PDT). The station is KKOH Reno on 780. The interferer is
> KCBC Riverbank/Modesto on 770, running IBOC.
>
> KKOH's field intensity at my location is calculated to be 3.27 mV/m. 
> KCBC's
> field intensity should be 0.349 mV/m, but there is a significant amount of
> fading, which is audible on the recording as the IBOC noise fades up and
> down. I'm 102.7 miles from KCBC (and on the back side of their pattern) 
> and
> 66.2 miles from KKOH.
>
> The MP3 file is 4:47 long. IBOC ceases at 2:14 into the recording. KKOH's
> carrier drops for pattern change about a minute later, at 3:16 into the
> recording.
>
> The receiver was a WinRadio, using synchronous detection, at 11 kHz
> bandwidth. The MP3 file sampling rate is 16 kHz.
>
> ----- Original Message ----- 
> From: Doug Vernier
> To: broadcast at radiolists.net
> Sent: Wednesday, July 19, 2006 8:30 AM
> Subject: [BC] Real cases of IBOC interference wanted for research purposes
>
>
> Colleagues,
>
> We are looking for real cases of reported IBOC interference to analyze for
> research purposes. Of particular interest is AM or FM IBOC interference to
> analog stations within the normally protected contour of the affected
> station.  We're also interested in interference outside the protected
> contour however; unfortunately, there's not much that can be done about 
> it.
>
> You may respond via the Listserv or to my personal email 
> dvernier at v-soft.com
>
> Thank you.
>
> Doug Vernier, Telecommunications Consultants
> V-Soft Communications
> Broadcast Propagation Software and Engineering Consulting
> WWW.V-Soft.com - 319 266-8402
> K0DV
>
>
> _______________________________________________
>
> Do you have a BDR? http://www.oldradio.com/bdr.htm
>
>