[BC] Wow, I wonder if y ou feel the same way about AM?

[Jeff Welton]

On Wed, Feb 3, 2010 at 4:13 AM, Dana Puopolo <dpuopolo at usa.net> wrote:
>The satellite radio people already do this in most urban areas. They have 6
>mHz allotted to terrestrial transmitters. Most times when I'm driving around
>(Los Angeles) and look, the ground based signal stregnth is over twice that of
>the satellite one. Think about this-only 6 Mhz is needed for almost 100
>stations of decent audio (or 200 channels of the crap they transmit now). Talk
>about spectrum efficiency! Take about 6 Mhz of the 420 band from the Govt.
>(they own all of the 300 mHz band-so they can spare a bit) and you can put
>EVERY radio station in a market on there-and then some. 5-10 well placed cell
>type transmitters can serve the entire market.

But Dana, since satellite radio doesn't transmit an analog component, you're talking about nearly the same potential spectral efficiency. A totally digital IBOC signal at 100 MHz has the capability (no, it isn't doing it as implemented right now, but the capability is there) of transmitting 8 data signals on roughly 400kHz of bandwidth.  Doing the math, that's equivalent to 120 signals at 6MHz B/W at a frequency that covers a much broader range. In the same scenario, if you want to compare apples to apples, there wouldn't be any analog to be interfered with so the interference argument would go away. With multiple owners, there is the chance at least of local service and the investment to each is ONE transmitter site, not a share of 5-10... As well there's the flexibility for different programming, better local service (yes, I know, not always going to happen, but at least the possibility exists) and other options that satellite radio can't begin to touch.

The whole IBOC argument centers around the fact that it was forced to operate in a hybrid mode (satellite wasn't, so that argument is invalid), to allow continued operation of local analog service, which certainly does cause some interference on the fringes and possibly closer in - although I'd argue that the reduction of multipath on an HD signal is a benefit worth considering, since it improves reception in the primary target areas (at least it will have a chance with -14+ dBc injection levels). I'll confess to not being up to speed on how badly it interferes in short spaced markets on the two coasts (hey, what can I say, look at my title, I only see an ocean when I'm home!), but given how bad the multipath was in analog on the east coast, the two times I've driven from Halifax to North Carolina, I didn't listen to any FM between Secaucus, NJ and Fredericksburg, VA anyway - between the processing and the multipath, the radio was useless down the I-95 corridor (and both of these trips were pre-IBOC).  At least now I can light up an HD receiver and not have to deal with the consistent bleeding, blending, fading and static, except when I'm at the limits of the signal - which comes pretty darned fast. The injection level increase should help that - and yes, in those situations, there may be cases where it further reduces analog coverage.

Maybe it's a symptom of the "need it faster, sooner, quicker" times we live in, but it makes me wonder that everybody realizes that FM took 30 years to get off the ground, but less than 10 years after the inception of HD Radio technology, it's all death knell.  With almost 15% of transmitters broadcasting it, getting receivers out there is what is needed most - but I've chatted with an older gentleman who owns a station in Mississippi who recalled how, in 1953, he couldn't get any of the local dealerships to install FM receivers either, so surely some others must recall similar battles.

I don't claim to have the answers - but in some cases there is decent programming on the secondaries that doesn't exist on the analog stations, in some instances HD coverage is acceptable as is and should be significantly improved with an injection level increase, in many cases there ARE listeners (who aren't station employees) and in many areas, there aren't complaints of interference. Yes, there are problems, but isn't the job of engineers to fix problems?  Wouldn't we have a better chance of saving radio in general if we focused on our strengths rather than bitching about how bad it all is?

Rich is, I suspect, a pretty respectable programmer - he could probably create a business by providing programming ideas to smaller stations and universities to help them maximize the return on their secondary channels and helping them to reap the benefits offered by PAD and data services.  Chip and Dana, I am pretty sure, are good engineers - Dana, you've got a lot of experience moving bits from one place to another and Chip, you do pretty good at finding ways to get RF to places it doesn't really want to go... again, there are a lot of places that these talents would be useful to help build the future as it exists right now, and to assist change for the better (it might be harder to change something from within than to sit in the rocker complaining about how good the good old days were, but it's infinitely more rewarding).

I'm not saying that HD Radio technology - as it exists right now - is the panacea that will save the medium.  But it's what we have to work with and, with a bit of imagination, there are some pretty wild possibilities where it could be used as a stepping stone to the future.  That future might have nothing to do with news on the 10's or the top 9 at 9 - it might be totally used for one way narrowband data transmission for focused applications, relieving some congestion on wireless networks or the wired internet, as an example - but it's up to people who are a lot more creative than I am to come together and work out what those possibilities might be. You're out there, I know - so since we're all strapped into this ride, let's enjoy the heck out of it and see what we can make happen!

Sometimes I wake up early - sorry y'all had to pay the price for that!!!

Jeff
--
Jeff Welton
Regional Sales Manager - Central U.S.
Nautel
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