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Message: [QUOTE="FOX TV, post: 100305, member: 4493"]Thanks Rick, Nice to know someone is looking, and after reviewing my list again, I did make an error on the WWCW channel number. WWCW is actually using channel 20, with a virtual channel of 21.1. I simply wrote it wrong on my list as habit from working there, and always referring to it as channel 20. TVFOOL is correct that the virtual channel number should be 21.1.  WCWG is actually using their old channel number as their virtual channel now, but they could conflict if the data was incorrect since the WWCW signals do get into their market. WWCW had to use a directional antenna for analog to avoid interference with the WCWG analog signal back in the day since WCWG analog was actually on channel 20, and WWCW analog was on channel 21. The WWCW digital signal was also on channel 20, and WWCW actually got the Digital channel 20 assignment, and WCWG is now on another RF channel.The channels received on the TV, and even on a spectrum analyzer are still line of sight, no matter what the elevation is. I am not sure how accurate the TVFOOL data is at over 2300 feet since it is only accurate to 500 feet or less. I am also using Longitude latitude coordinates from a GPS unit, instead of zip codes. This could explain the discrepancy, and the spec analyzer showed RF signals that the TV would not receive a picture on. This could be due to signals below the threshold of the TV's Chipset that the spec analyzer can detect but the TV cannot detect. They both showed different results using the very same antenna. TV FOOL also uses the predicted coverage database from the Longley-Rice modeling software, and my experience in actual field strength tests shows a big variance in actual results when compared to real time field strength tests and the results generated by the Longley-Rice modeling software.This could also be due to antenna aiming since my antenna is much more directional than other designs. Movement of just an inch can drop signals 1 to 3 db, and if already at the chipset threshold, it may not produce a picture on a TV set that the spec analyzer can detect, but this is my intent with this design since multi-path is such a big issue with DTV signals, and it was my intention in the design to reject multi-path signals the the maximum extent possible. TV sets use the pilot carrier to detect a signal but they also "LOOK" for data streams to lock onto. The spec analyzer "LOOKS' for Rf energy as its main focus, and then analyzes the data it contains, so this is another possible reason for the differences in channel data shown that may or may not be received by a TV set.There are also many other possibilities that can cause a lack of reception on a TV set such as a mis-tuned transmitter exciter, or non linear transmitter amplifier tuning, or even a station running at reduced power due to problems with the transmitter, antenna, or the Rf transmission system etc. Transmitters have many built in safety systems that can reduce power, or even shut it down if problems are detected.  There can also be maintenance being done to a transmitter or tuning in progress that requires reduced power levels. there are many reasons that could explain why something listed in TVFOOL may not be receivable at certain times. This directionality of my antenna can also present problems when scanning for new channels with a chipset that does not allow manual entry of channels, which a lot of them do not allow. I am running into this problem with newer sets, but I can get around it with an older tuner I have that does allow manual channel entry. This issue should be addressed by chipset designers since channels can come from multiple directions in many markets, and with highly directional antennas now being used, not all channels will be detected, and without manual entry, they will not be viewable, even though the signal is available to them that is coming from a different direction. this is a big problem that should be addressed, or set up in an industry standard basic spec sheet for all TV tuner chipset manufacturers.[/QUOTE]

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