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Discussion Starter · #1 ·

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.


· Registered
5,414 Posts
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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