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amdx amdx is offline
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Default Increasing Cable TV signal strength

On 2/8/2012 2:47 PM, Dave Platt wrote:
In ,
wrote:
I'm on a boat, about 170ft from the utility post.
Recently our cable company switched to the wonderful world of
Digital TV. I got the new digital converter and had no picture.
I took the box back and got a second box, still no picture. So now I
suspect a weak signal and confirm that it is the cable length. The cable
company came out and gave me a better cable than I had installed. At
this point I have a picture but it is intermittent. The signal at the
utility post has 3 outputs and had a four way splitter, I suggested the
cable guy put in two 2 way splitters and give me the stronger (first) tap.
That got my signal to work almost all the time. I'd like to get the
signal to work 100% of the time.
I don't has access to electricity at the utility post, so an amp is
out. Although I could try an amp at the cable box end. Is that reasonable?
I would run two cables if there was a way to make it increase signal
strength.
Getting anymore from the cable company is not an option.
Any ideas to get a better signal?


Adding an amp at the cable box isn't all that likely to work... you
can try it, but don't get your hopes up. Unless the amp has a
significantly lower "noise figure" than the RF front end in the cable
box, all you'll be doing is adding noise... the desired signal will be
stronger, but the noise will be stronger yet.

Something you could do, is add a single-port RF amplifier right at the
utility post splitter, where your tap comes off of the feed. You can
buy amplifiers of this sort which are designed to receive "phantom
power" through the coax cable... you'd install a "power injector" at
your boat, which feeds a DC voltage up the coax to the amplifier.
This is probably your best bet:

- It would amplify the signal before it's attenuated by the 170-foot
cable run.

- It won't require a power supply at the post... just at your
boat, where you already have power.

- It shouldn't interfere with the other taps on the
splitter, even when the amplifier is not receiving power from your boat.

You'd be looking for an "antenna mast" type of preamplifier. The
Channel Master 0068DSB or 7777, Winegard AP-8700 or AP-8275 or
HDP-269, AntennaCraft 10G212, or one of the Blonder Tongue Galaxy III
models might do the job for you. You'll probably want a "75 ohm in,
75 ohm out" model, which would connect directly to the 75-ohm coax.


Hey thanks for the part numbers, I'll look into these.
Mikek