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Discussion Starter · #1 ·
Just installed a HiPix and it works - kinda sorta.


Two weird things:

1> It shows the NTSC channel numbers, even though I am DEFINITELY receiving the digital transmissions (signal strength around 50) - which in the Bay Area are on channels 19 & higher. If I switch to NTSC, I get reasonable SD reception of all that dreadful commercial programming.


2> In ATSC mode, I get all the commercial channels EXCEPT KQED-PBS(the only one I really want to see). I've tried manually tuning the HiPix to both channel 30 and (in deference to my HiPix's proclivity to display NTSC channel numbers) channel 9. I get no signal indicated at all.


I can practically see the birds nests on the Sutro tower from my house in Daly City high on Mt San Bruno.


Any ideas?
 

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What you are seeing are "virtual" channel numbers, which are identical to the station's analog channel assignments. This was done so as not to confuse consumers.


The theory was, STBs would go out and automatically find any active DTV channels, and save them to memory. The tuner would remember the real (physical) UHF or VHF channel. The STB, though, would show the user a "virtual" channel, so they would know they had tuned in their old, familiar channels.


The data that "bursts" this information is part of the station's Program and System Information Protocol, or PSIP. Not all DTV stations have PSIP implemented the same, or even at all. So, some of your stations may show a physical channel, while others show a virtual channel.


Your reception problems with KQED-30 may be related to the signal arriving at the antenna. You may have close-in echoes and multipath, causing signal cancellation. have you tried moving an antenna around - even indoors - while tuned to channel 30, just to see if you can pick it up?


KC
 

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Discussion Starter · #3 ·
Hot tip, Kelvin. Thanks.


I don't know why KQED's signal should be so much weaker coming from the same tower as others which seem to have adequate signal strength. But my antenna was the problem. I initially tried whatever it is I have on the roof. It has worked OK previously for VHF, but I never was interested in UHF before, and it is clearly no good for DTV (at least as it's presently oriented and hooked up). So I tried a $3 clip on bow-tie from Radio Shack. Definitely underkill. Decided to try their $20 outdoor UHF-only yagi/corner-reflector style. Rated for up to 75 miles, I figured it oughta be good for 1.5 miles. It was better, but even with it stuck out the window, KQED-30 was a lousy 35% sig strength.


When I bought that antenna, the manager of the Shack said their set-top double bow-tie UHF for $18 was a damned good antenna - but I figured the yagi'd be better. Wrong. I went back and snatched up one those weird lookin' brassy gold babies and bingo. My KQED signal jumped to 70%. It looks like some sort of sideways barbecue grill with built in turkey support standoffs - but it works great.
 
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