Originally Posted by Arcade
On the way home from work I thought of what might be causing the weaker signal from 12-1. Richard or someone who knows more will have to confirm this idea but here it is.
Channel 12 broadcast on UHF digital 50-1. From what I understand, this is a horrible channel number to have, as it take more power to broadcast at higher UHF numbers.
I believe Channel 6 at 21-1 needs less power to push their signal out.
Richard, is this correct?
I have also heard that when the analog shutoff date comes that channel 12 has elected to go back to broadcasting on digital 12-1 which should save them a lot of electric costs.
Some people may have to get a VHF antenna combo to pick them up then but I have heard that a lot of UHF only antennas will pick up channels 9-12 with little to no problem. Since they will only be one channel down from the UHF channel 13 I would guess most people will continue to get them anyway.
In the analog world, KBTV (4) and KFDM (6) each put out 100KW in the low VHF band. KBMT (12) has to put out 316KW to get about the same coverage on their high VHF channel. As you go into UHF, you get to 1,000,000 watts to get the same coverage.
Digital should follow the same rules; the higher the Frequency, the more power you need for a given coverage area. However, the digital modulation scheme puts more actual power in the signal than an analog signal will. So the difference may not be as pronounced as one would expect.
Each TV channel is assigned a 6 Mhz frequency range. Channel 13 uses the frequency range of 210-216 Mhz. Channel 14 starts at 470 Mhz (channel 21 starts at 512).
So in theory, a UHF antenna should not pick up channel 12 very well. In actual practice however, it probably will. One of my "guys" just bought an HDTV set and put the UHF only antenna in his attic. He picked up channel 11 out of Houston very poorly, but it was there.
Bottom line is: it can't hurt, and costs nothing to try.