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

[David L. Hershberger]

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