Quote:
Originally Posted by gcd0865
...I've seen Tower Guy's interesting calculations of total signal strength (but not sure how to calculate it myself from my TVFool report)...
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If I got it right, here's how GroundUrMast calculated signal strength from TVFR. Keep in mind that Noise Margin (NM) is another important metric to look at.
Start from the absolute Signal Power level (dBm) on your TVFR, e.g. WDIV-TV on 4.1 virtual channel at -23.3 dBm - this is the signal level at the antenna input (in the air at your location).
Add your antenna gain for that channel / frequency (or a conservative average gain if not known), let's assume +10 dBi (it looks like you do not need to translate from dBi to dBm): you should have -13.3 dBm signal level at your antenna output.
Assuming you factor in a preamp, -13.3 dBm is what your preamp receives in input.
Add the preamp gain if you have one (e.g. 12 dB) to that figure to get your signal power at the preamp output: -1.3 dBm in this case (again, it seems that you do not need to convert from dB to dBm). From GroundUrMast calculation, it seems that the preamp noise only affects NM and not signal level.
Subtract total signal losses (cable, splitters, misc), e.g. 10 dB and you get signal level at the tuner input, -11.3 dBm.
Let me know if you notice differences versus Tower Guy's calculations.