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Hi,


My antenna is 200 feet from my house which forces me to use 250 feet of rg6 to

reach my HTPC. I have a new 300 foot roll of rg11 in hand which I will be installing

in a few days, hopefully this will recover 3 or 4 db of signal. But even with this

increase I believe I am going to need to use a line amp in addition to my mast

mounted cm7775. My HTPC has two tuners and if I use a standard

splitter to feed both tuners I loose two of my weak channels.


My question is can I use a line amp along with my mast mounted cm7775?

And if so how much cable length do I need to put between the cm7775 power

supply and the line amp? Also, is a line amp the same thing as a distribution

amplifier? It seems they both simply amp the signal while the distribution amp

also splits the signal. I read somewhere that putting a line amp to close the the

preamp power supply can cause problems.



Thanks!
 

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It will all depend on signal levels coming in and the levels out of the amp. Strong signals, whether they are TV transmitters or something else, can overload a preamp. Strong signals from a preamp can overload a tuner or a distribution amp.


Here at KSL, we have our antennas on the roof, and have about 600 feet of RG-11 coming down to the basement headend. With UHF, the 20 dB preamp overloads slightly, already. We still have enough to usually split 8 ways. I added a 7 dB distribution amp to get levels up slightly, and to split 16x, but it's borderline on overload. Plus, we have two dozen stations in the UHF band.


Similar thing with VHF-HB (7-13). We get plenty enough signal to overload a preamp already, so we have to attenuate it at the antenna.


We still have sufficient signal on VHF-LB (2-6), via 300-400 feet of RG-6, with no preamp.


So, I'd say....try everything without amps, using the RG-11. Then, try preamping the UHF only. If necessary, then try a separate preamp just for the VHF-HB if needed. Your CM dealer should be able to suggest whatever multiplexers you might need to add the second preamp.
 
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