Originally Posted by CA_Guy
I have not tried to "fine tune" the direction my antenna is pointing, but other than that, YES I desire to get as many stations as I can. I plan to install a separate UHF only antenna later this summer pointed to the Chico area.
My main antenna is the best UHF/VHF combo that Radio Shack sells (or used to). It's just over 20 feet above my roof, but I am already at a good elevation in Fair Oaks. I am not using a pre-amp at the antenna (I had one originally, but it blew out), and now only run an amplifier just as the signal enters the house. That signal is split at least 12 ways, and not all at one place.
I would definately recommend that you get a preamp, especially with your installation.
How are you splitting the signal? Are you using regular TV splitters, or are you using taps?
I recommend using taps with thast many splits, ( if you are not already), as it taps only the amount of Db's you need, (or that is written on the tap you get), and passes the rest with a 1.5 db average loss. Unlike a regular 2way splitter that splits the power in half, with a 3 DB loss on average for each split. In this way you won't have to use an insanely amount of dbs to keep the system operational, and you won't be subjected to a possible over amplification problem on tvs closer to the amps.
I am getting all stations from Walnut Grove with 100% decoding. The strongest stations from Sutro have been KPIX29 & KQED30 so far. The toughest stations to get have been KTVU44 & KGO7. I still get quite a few analog low power stations as well including one on channel 45, which keeps me from getting KBCW45.
I am anxious to see what stuff looks like when they have the work on Sutro completed.
With 12 splits in the line, I would think highly about engineering a small headroom for best performance. You wouldn't need anything super expencive like for a hotel or something like that, using strip amps, channel converters, band pass filters and the like.
I'd at least weigh the pros and cons of a pro quality signal amp, and taps etc...
For a loose example, and rounding numbers to an even whole number, let's say I have four rooms, and have a 20Db amplifier.
One tv is right at the head of the system. One 4db tap, leads off to the first tv, vcr, tivo etc..., and passes 15db to the next split. lossing 1db due to the tap. This gives you 4dbs at the first tv. A modern tv can handle 5dbs without overloading, and it gives you a little extra for vcrs, or other equipment. 0db at the tv is ideal, neither positive or negative.
Factor in the cable length and signal losses. Lets say I lost 1db due to cable length, so at my next tap, the signal strength is at 14db, another 4db tap, brings the passing signal strength to 10db.
Then with the 1db signal losses through the cable it is now at 9db at the next 4db tap for the third room. Passing 5db to the next tv.
Then with the fourth room with everything being a constant 1db loss due to cable length the dbs at the final tv should be around 4dbs.
Be aware the above is just an example, and none of the cable lengths, losses or db alowences are going to be that perfect in the real world.
The system you have though, seems to be working for you though, so the old addage, if it ain't broke don't fix it may be wise too.
Also it's been 15 years since I designed a headroom, (not including my own) so if I left anything out, got something crossed in my old brain, or if there are new digital quirks I don't know about... corrections are welcome.