But even after my long post I'm still hung up on your original comment.
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My confusion with the CW station so weak, is why my WACY station comes in at 68% reliably even in the day time when it should be just as weak.
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Why indeed?
I looked at the terrain profiles of both, and I looked at the coverage maps for both; very similar. One difference that I can think of are terrain differences of objects above ground elevation:
DTV Coverage and Service
Prediction, Measurement and Performance Indices
Oded Bendov, John F.X. Browne, Charles W. Rhodes, Yiyan Wu, and Pierre Bouchard
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Abstract-- It is now clear that methods used to predict the replication of NTSC service in the US were idealized and, for the most part, not validated. The need to review the methods and procedures now in use is highlighted by the various field tests conducted in the US and elsewhere.
This paper outlines potential improvements in the modeling, methods and procedures now in use for prediction and measurement of DTV service.
INTRODUCTION
Early on, even before the 8-VSB standard was adopted, it was suggested that low-power HDTV transmission, as low as –12 dB average power relative to NTSC peak visual power, would provide for service replication to at least the Grade-B contour of NTSC stations.
It was generally thought that with incident field strength of 40.8dBu at 615 MHz, DTV receivers would be able to decode the signal and that higher field strength would not improve the reliability of reception.
Those predictions were based on an idealized receiver, a multipath-free propagation channel and coverage prediction
software that uses only terrain elevation data, but not terrain clutter data. Clutter data specify the land cover, such as forest, water etc. on top of the terrain elevation data. For these and other reasons, such as time availability statistics, it is now believed that the current predictions of DTV coverage and service will not be realized.
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OR AS TVFOOL SAYS:
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Please understand that this is a simulation and can only be treated as a rough approximation. Reception at your location is affected by many factors such as multipath, antenna gain, receiver sensitivity, buildings, and trees - which are not taken into account. Your mileage may vary.
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Another difference I see is that because of transmitting antenna patterns WCWF only sends about 15 kW of its 800 kW Maximum ERP in your direction, but WACY sends 35 kW of its 50 kW Maximum ERP. See attachments 3 and 4 for relative field polar plots.
But, as you can see by the color code, you are on the fringe for both.
color code here:
http://www.tvfool.com/index.php?opti...id=15&Itemid=1
In very rough terms, the colors can be broken down as follows (not related to Antennaweb):
- White is extremely strong. Beware of signal overload on amps.
- Red-yellow-green are all quite strong. You can expect reasonable coverage with an indoor antenna.
- Cyan is where it's advisable to move the antenna up to the second floor or attic.
- Blue is where it's probably necessary to install a good antenna on the roof.
- Purple is quite weak and you really have to work at it for any chance of reception.
Anything useful here or are my posts tl;dr?
