Not sold on IBOC
Mar 1, 2002 12:00 PM
I disagree with you on your Viewpoint [Making the Grade] in the January 2002 issue regarding IBOC. Digital enhancements should be in the receiver, not in the transmitter.
DSP should be standard in receivers, particularly in AM receivers. Analog C-Quam AM stereo provides decent sound on a decent receiver, unlike so many receivers today with 50-cents worth of parts.
The IBOC FM report states that FM IBOC doesn't cause "significant interference." This is unacceptable, as it should cause no new interference. Is the FCC forgetting its rule that all new services must be backwards compatible and not cause new interference problems? NTSC color is compatible with black and white TV, C-Quam AM stereo is compatible with mono AM and FM stereo is compatible with mono FM. All of these services managed to be backwards compatible. Does the FCC really care anymore?
IBOC FM must be 99 percent compatible with the current FM stations or it's back to the drawing boards. IBOC AM is a technical nightmare with skywave reception, and it is unlikely that an IBOC AM night-time signal will sound any better than a poor Internet audio connection. IBOC AM is also incompatible with the 350 stations currently broadcasting with C-Quam AM stereo. If IBOC AM isn't stereo, then music won't migrate back to the AM band.
IBOC AM has to exceed FM and not simply be "FM-like." If all of the efforts spent on IBOC were instead directed at complex DSP algorithms, AM noise-blanking systems, diversity antennas and AMAX quality receivers, then analog radio would exist and thrive with even higher quality than it does today.
IBOC must be a factor of ten better than analog in order for the general marketplace to want it. I also don't believe that the Ma and Pa radio stations can afford IBOC upgrades, and IBOC is just one way for Clear Channel and Infinity broadcasting to force these little stations that refused to be assimilated (purchased) by their bloated legal broadcasting monopolies off the air.
The marketing hype behind IBOC has forgotten two important things: people are basically happy with analog stereo AM and FM, and they are not happy with the programming. Listening to Howard Stern in digital doesn't make his show any better.
Innovative Controls Corporation
Nice Viewpoint in the December 2001 issue. [Something to Celebrate, a review of Marconi's transatlantic tests.] We don't look back at our history enough.
Robert E. Richer
Crossed Field Antennas, Ltd.
Solid on solid-state
I found John Battison's RF Engineering, January 2002, on solid-state tower lighting informative. Last month I changed both of our Franklin antenna towers to the Dialight system for my side lights. The greatest resistance to my decision was that solid-state lights have no history of damage from lightning. I countered with the point that we have very infrequent lightning activity, and if a lightning strike hit the tower hard enough to knock out the solid-state lights that I will have a much larger problem.
The installation went very quickly. There is no perceptible difference in brightness between the old tungsten units and solid-state. Also, I am looking to reducing the amount of bulb changing and money involved with that activity. I plan to change the rest of our towers to this system in 2003.
Ross du Clair
Clear Channel Sacramento