Can you see us now? Good!

re: Can you see us now? Good!

carlb — Fri, 20 Mar 2009 20:18:31 GMT

I believe the standard FCC assumptions are:

The receive antenna is on a ten-metre (31-foot) pole on the outside of the building

The antenna is very directional (somewhere around 10dB gain, depending on frequency)

The antenna is pointed directly at the station (which may require a rotor)

The US EPA's estimate of 2.8 TV sets in an average American household can be disregarded as the inability of this big antenna and rotor to point in more than one direction at once will hopefully magically go away if simply ignored for long enough.

And, one last assumption: Even with this full-size outdoor antenna, which may cost hundreds of dollars to install, any station delivering worse than a B-grade signal in analog simply does not exist. It's an illusion. Those snowy images are a figment of your imagination. No one, therefore, will notice when one or more major-network signals abruptly goes over a digital cliff and forever disappears after an ill-advised but government-mandated move from low-VHF analog channel to digital UHF leaves dramatically-different coverage in certain problem areas.

All make sense so far? Good. Once these key assumptions are made, 210 sets of maps can be generated, one for each US market in Nielsen's TV rating books.

Hopefully Weird Al's station, already on UHF, will retain its coverage and its endless supply of ads for Spatula City, 24 hours a day. It'll usually be the long-established networks who've been around since the days of medium-wave radio that'll have the huge drop in coverage as they are forced off low-VHF channels onto other bands.

At least this handy map shows who's losing coverage, now that it may be too late for stations to do anything about it. Would a spatula work as a UHF antenna?

The maps will claim a southern portion of Jefferson County (Watertown) just lost NBC - but it's safe ignoring the rest of Watertown as the signal being lost was at best fringe-grade and therefore doesn't count. Similar pattern for Utica and CBS as Syracuse becomes a UHF island. Just try not to ask exactly what anyone would want with 2.8 of a television set (maybe the extra 1.8 TV's are intended to keep 1.8 kids distracted?) or where exactly one goes to get the .8 of a converter box which wasn't covered by the half-hearted attempt at a coupon programme.

Oh, and the rural areas who lose everything even with the big antenna? They don't matter, because stations who no longer can reach those viewers hopefully pick up a TV set or two in some other area to make up for it. As a small number of people live there, and as likely many are country bumpkins engaged in irrelevant pursuits like growing food instead of more important tasks like sitting in Washington drawing maps to illustrate why the TV doesn't work anymore, statistically they're too few to be noticed.

Also, any problems in cities are most likely caused by using antennas other than those in the standard set of FCC assumptions, so these viewers can be ignored too.

With that out of the way, one can go back to making more clever PSA's about EDTV and rabbit ears. Bonus points, of course, for repeatedly telling the subset of viewers who understand absolutely nothing about anything digital that all the answers can be had from Antennaweb or some other Internet site. There's plenty of good info out there, online, right at the fingertips of those who presumably need it the least.

At least a web address or two always seems to fit well in a short :15 or :30 PSA... and one wants a quick, short, marginally confusing message as this by law will need to be repeated 84 times a week on every channel, including the digital .1's.

re: Can you see us now? Good!

carlb — Fri, 20 Mar 2009 20:25:37 GMT

Overall, it looks like the U-to-U's (those channels already on UHF, and staying there) aren't doing too badly. If WSPX is an exception, this may be because they've gone to channel 15. There already is a 15 (CBLFT, canal quinze Belleville, «ici Radio-Canada!») so the power levels allocated to WSPX in international co-ordination may be a wee bit smaller than what could've been had on another channel. I think the Belleville station (a repeater, but licensed as full-power) had 400kW analogue and WSPX had substantially less digitally (25kw, IIRC). The other exception is WNYI (51 Ithaca) which has no digital signal and operates a tiny analog transmitter on a full-service license - possibly to hold the spot on the dial until the station can be moved or sold. WNYI's owners went bankrupt in December.

re: Can you see us now? Good!

carlb — Fri, 20 Mar 2009 20:46:41 GMT

Correction: WNYI is 52 Ithaca, not 51. Key distinction as it's one more factor ensuring that they cannot stay there (7-51 are in core, 52 is not). They had been licensed to put up a very weak digital signal on WUTR's old frequency but have no means to do so.

re: Can you see us now? Good!

JH Engineering — Fri, 20 Mar 2009 21:59:36 GMT

Thanks for the comments... you are likely correct about the FCC's baseline assumptions, but it isn't clear, particularly since they use different modeling parameters for consumers than they do for broadcasters.

If you take a look at the FCC's map for WSPX, the vast majority of viewer loss is in the east-west direction, not toward Canada. It seems to me that they could easily have adopted a more ellipical antenna pattern and retained their viewer numbers without posing a threat to CBLFT.

WNYI's digital on channel 20 still needs to avoid interference to WBGH-CA in Binghamton, so there is a practical limit to how much power they can put out.

It's been a marathon week... time to head home, where the biggest technical challenge is feeding the cats!

-- Jeff