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Discussion Starter · #1 ·
Does anybody have any idea what is the minimum signal stength needed to "lock-in" on an ATSC station? I ran the numbers from one of the Signal Strength websites for my location and the locals are all over 100 dBf, but the stongest distant signal is 49 dBf. So, my gut says, "if I amplify by 60 dB, I should get the same reception as a local stations," but my mind knows that it's a bit more complicated than that!


A single Televes DAT75 antenna gives me 19 dB of gain, and one of the Channel Master preamps can give me another 26 dB of UHF gain. So now I'm at 49+19+26, or 94dBf, minus whatever losses from cable run, splitters, etc., so let's call it 80 dBf. Is that going to be enough to get a lock on my Dish 6000? I remeber in the Good Old Days, FM tuners had a dBf or dBm rating for a given dB S/N ratio, usually where you could listen to a station and make out what they're broadcasting. Is this information actually available anywhere, for any ATSC receiver? If my 6000's minimum receiver level were 60 dBf, I'd feel a lot better than if it were 80 or 90 dBf.
 

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I don't know the answer and wish I did. I have noticed that my DISH 6000 won't really "lock" on any signal less than 60% on the onscreen level.
 

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I have a distant station that I am trying to pull in (apprx 80 miles). I can get a lock if the signal strength is above 50%. If the signal strength stays around there I get a lot of drop outs and the picture is pretty much unwatchable. I get a perfect picture with no drop outs if the signal strength stays above 60%.
 

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Discussion Starter · #4 ·
Ah, my bad. The levels that were reported are in dBu(microVolts), not dBf(femtoWatts). So, the 60 or so extra dBu that I need may only need 30 dB of amplification (volts vs. watts). Or, is the amplification published for amps and antennas referring to voltage ratio as opposed to the wattage ratio?


The 6000's display is a signal quality meter, not a signal strength meter. It refers to the number of errors present in the signal, 100% being perfect. (Although, on my 6000, it says ":0" instead of "100", as the colon is the next ASCII character after "9")
 
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