cable signal - control RF
yksmir
Could you please explain something to me about my cable box from Time
Warner? I have an Explorer 2100 by the way. Through Time Warner on
channel # 199 I can see certain numbers... two specific ones: Control
RF and Reverse RF numbers.
Time Warner doesn't seem to be able to tell me what the "good" range
is for these items in obtaining a good picture. They recently changed
the electronics on my telephone pole and now my tv has gotten grainier
on certain channels.
before the change my numbers were:
control RF: unknown MHz, -2 dBmV
Reverse RF: unknown MHz, 36 dBmV
after they fiddled with the electronics on the pole I now get:
control RF: 103.750 MHz, -16 dBmV (it sometimes goes down to -14 dBmV)
Reverse RF: 20,000 MHz, 36 dBmV
what is your acceptable range on these numbers for a good picture?
Obviously the number that changed was the control RF. Could this cause
my graininess? The unit has a digital bypass where I can go to
channels 1502, 1504, 1505, etc... to get the analog equivilent of
channels 2, 4, 5, etc... When the picture would pixilate on windy or
rainy days I would go to the analog channel versions and it would come
in just fine. Now those analog versions are really grainy too. And all
after the supposed upgrade. They told me my box must be acting up,
that they've had trouble with them. All was fine before the line
upgrade.
Thanks
yks
weitrhino
a data stream into the box for subscription commands and guide information.
A -16 does indicate something has gone awry with your signal.
weitrhino
"yksmir" <yks...@yahoo.com> wrote in message
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OldGoat
Not sure, but they if they are incoming and return leg signal levels, the
slope is reversed. The higher the frequency the higher the signal strength
should be,, since high frequencies attenuate (weaken) faster than low ones.
it would seem they could only be measuring DB at the converter, since there
can be all kinds of goodies to knock signal down (particularly splitters)
before the signal reaches the box.
Generally you want +10dbmv to -10dbmv at the box input. So zero is not a bad
thing, but I liked to shoot for +5 to zero when running an installation.
There used to be a nasty little habit installers would use when wiring a
house with a need for a lot of signal (a long service line to the house,
many outlets) called 'hot tapping". They basically put a different value tap
to siphon more signal off to that particular house from the feeder(main
service lines above or under the ground). Of course that screwed system
integrity and everyone else downline until the next system line extender or
amplifier where hopefully the signal was reboosted to proper levels. So how
bad an effect hot tapping would have depended on where you were in the
feeder run.
Water is also a very bad thing and can effect signal greatly, but the good
news is all the cable outside the house is their to maintain properly, it's
BS if they say they need access or you to be home to check levels. So book a
service call and if they're going to "doorhanger" you for not being home,
tell them to put the signal levels at the entrypoint or interface to the
house in writing for you. Nothing will stop a tech from making up good
levels and taking a long lunch on the excuse you aren't home, but being
there the next time and showing them all different levels and that the tech
never bothered to look can be a complaint to the franchising authority
(usually a county cable office) and give a bit of a reaming to cable
technicians who give the industry a worse reputation then they deserve.
Though that is hard to do to begin with. Cable is the most money for least
possible service, and if you are going to have to service your own system
it's time to hang a dish and cut out the middleman. I am ashamed to admit it
but I was in the game for a long time, but now consider my confidentiality
agreement null and void. When it was a $25 a month service, and you got a
$25 a month service was one thing. When you pay $75 for a $25 a month
service it's something else.
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"yksmir" <yks...@yahoo.com> wrote in message
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