Originally Posted by zaphod7501
bsandy, 31 digital is a very weak signal aimed at Peoria (from East Peoria transmitter) Their PSIP info may be wrong, too. Try manually tuning the physical channel 30 if possible.
In the analog world 38,39,40,41 could never be in the same market because of massive interference. There is normally a gap of at least 6 - ch 47 is an odd man out and it causes problems) It would be almost impossible to drop the level of 40 (strong WHOI digital) without lowering 39 (weak WAOE UPN) also. Some moron must have decided that digital transmissions would not be affected by adjacent channel and co-channel interference. Anyone with a background in UHF signal distribution systems could have told them it wouldn't work right; but they didn't consult me. My knowledge comes from installing UHF systems in the 70's not from engineering texts. Nowhere else in the country are you likely to find a 100% UHF market so there probaly were no "experts" they could consult about UHF transmission problems so they relied on Electrical Engineers who had never set up a UHF antenna in a trailer park. A trailer park is historically the absolute worst place to get TV reception in the world.
The idea was that tuners would have enough sensitivity (mandated by the FCC)
to be able to handle adjacents just fine, which they normally do, but hold on. Here in the Chicago market, we have 3 on UHF as adjacents---51 (WPWR-UPN), 52(WLS-ABC), and 53 (WGBO-Univision), and since I am 60 miles west of Chicago, I also get WREX-DT on 54. And I get 'em all without any problems.
Your problem was also seen in Milwaukee. Two DT stations, 33 and 34, are next to each other. 34 was easy to get; they were at 900 kw. 33 was at a measly 6 kw
or something obnoxiously low like that. The FCC says that if you put two adjacent DTV channels at full power on the same tower or within a few miles (I forget what the maximum separation distance allowed is exactly), then you won't have interference problems. But you DO have problems when one of the two adjacent DTV channels is at low power. When 33 went to full power last October, the problem was solved. Nobody in Chicago has problems with 51, 52 or 53 due to intermodulation (overloading). They're all at full and reasonably high power.
Wanna hear something funny? Oh, you're going to just laugh your socks off at this: When WMBD-DT goes full power, they'll be at 1 mw (million watts). Any DTV stations adjacent to them at much lower power will now have the problem WMBD-DT has! Irony can be ironic.
WHOI and others are pretty much at full power even though they are much lower than what WMBD will be. WMBD will be a stinkin' blowtorch when they turn on the juice full blast.
All CBS stations will have to be HD and full power by the Super Bowl (2007), if CBS HQ has anything to do with it...WCIA in Champaign will have a blowtorch and a half signal almost to the city limits of Peoria...