"JIMMIE" wrote in message
...
On Feb 8, 2:00 pm, amdx wrote:
Hi All,
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?
Mikek
PS.
When the signal fails it seems channel 41 is ok and above 42 it breaks up.
Curious to know if there is an unusual frequency jump between those two
digital channels.
Google your cable box model. You should able to find ifo on how to
pull up a menu that shows signal strengh. -60dbm is about where my
sigal starts droping out
Jimmie
================================================== ===
Yes, but be mindful of the difference between dBm and dBmV. The cable
industry often deals in levels on the dBmV scale.
There are places like this ...
http://www.maxim-ic.com/app-notes/index.mvp/id/808
where you can see some conversion equations. Jimmie's -60dBm equals -11.25
dBmV. Same power level -- different scale.
I have long known level requirements for the TV tuner's cousin, the cable
modem. The common DOCSIS 2 cable modems are usually spec'ed for -15dBmV to
+15dBmV and the smart operators try to keep inside +/- 12. Thus, you can
see that Jimmie's -11.25dBmV is near the low limit and that dropouts become
more likely in that neighborhood.
I little bit of google snooping revealed that DTV cable boxes would like
0dBmV and will usually be okay with -10dBmV to +10dBmV. Almost the same.
i hope this helps.
"Sal"
"Sal"