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cs
08-21-2003, 07:13 AM
My cable TV is split into 2 lines and on one of those lines it goes through the satallite, VCR, and DVD player before it gets to the TV. And I plan on putting another split in the line so I can watch football in the shop.

My cable signal was never good to begin with and with all the jumps it makes I end up with snow. So I've thought about getting one of them $20 signal boosters at Radio Shack. Are they worth it?

Chad

cs
08-21-2003, 07:13 AM
My cable TV is split into 2 lines and on one of those lines it goes through the satallite, VCR, and DVD player before it gets to the TV. And I plan on putting another split in the line so I can watch football in the shop.

My cable signal was never good to begin with and with all the jumps it makes I end up with snow. So I've thought about getting one of them $20 signal boosters at Radio Shack. Are they worth it?

Chad

cs
08-21-2003, 07:13 AM
My cable TV is split into 2 lines and on one of those lines it goes through the satallite, VCR, and DVD player before it gets to the TV. And I plan on putting another split in the line so I can watch football in the shop.

My cable signal was never good to begin with and with all the jumps it makes I end up with snow. So I've thought about getting one of them $20 signal boosters at Radio Shack. Are they worth it?

Chad

Popeye
08-21-2003, 07:45 AM
hmmm,

first question is, why does cable provide signal thru DVD player, i can not see what that connection serves.

next observation is, if you have a weak signal and try to boost, will this also boost (snow) noise.

finally here are my two tricks for cable..

tin foil... wraped loosely around coax connectors can help (shield) stray e.m. signals and with a little tweeking gives great picture.

moving the cable, particularly off vertical and away from walls, helps clear 60 cycle power line interference.

cheers.

Popeye
08-21-2003, 07:45 AM
hmmm,

first question is, why does cable provide signal thru DVD player, i can not see what that connection serves.

next observation is, if you have a weak signal and try to boost, will this also boost (snow) noise.

finally here are my two tricks for cable..

tin foil... wraped loosely around coax connectors can help (shield) stray e.m. signals and with a little tweeking gives great picture.

moving the cable, particularly off vertical and away from walls, helps clear 60 cycle power line interference.

cheers.

Popeye
08-21-2003, 07:45 AM
hmmm,

first question is, why does cable provide signal thru DVD player, i can not see what that connection serves.

next observation is, if you have a weak signal and try to boost, will this also boost (snow) noise.

finally here are my two tricks for cable..

tin foil... wraped loosely around coax connectors can help (shield) stray e.m. signals and with a little tweeking gives great picture.

moving the cable, particularly off vertical and away from walls, helps clear 60 cycle power line interference.

cheers.

cs
08-21-2003, 07:57 AM
Popeye your right about the DVD player. On further thought I'm not running through the DVD. It use differnt connections.

I was thinking about going back as close to the source as possible to add the booster, so it boost the signal and not the snow. I believe the snow is caused by the long runs, the splits and going through the differnt connections.

I've wrapped cables in foil before for my stereo and it works okay and it probably would help.

Chad

cs
08-21-2003, 07:57 AM
Popeye your right about the DVD player. On further thought I'm not running through the DVD. It use differnt connections.

I was thinking about going back as close to the source as possible to add the booster, so it boost the signal and not the snow. I believe the snow is caused by the long runs, the splits and going through the differnt connections.

I've wrapped cables in foil before for my stereo and it works okay and it probably would help.

Chad

cs
08-21-2003, 07:57 AM
Popeye your right about the DVD player. On further thought I'm not running through the DVD. It use differnt connections.

I was thinking about going back as close to the source as possible to add the booster, so it boost the signal and not the snow. I believe the snow is caused by the long runs, the splits and going through the differnt connections.

I've wrapped cables in foil before for my stereo and it works okay and it probably would help.

Chad

Popeye
08-21-2003, 08:32 AM
okeh. sounds like you got some good clues there.

check also that your cable is in good shape. typically, from my experience, leaky connectors are the culprits in poor signal; particularly sound is bad if many bad connectors have exposed shielding layer.

along with snow, getting a 'hatching', ie diagonal thin lines walking across the screen? this is also connectors picking up unwanted pollution.

finally one more hincky way to fix is to consider the length of you cable. as you know, 1/4 and 1/2 and 1 and 2 times wavelength make excellent antanae. try snipping off a little cable to find an odd length that aint happy place for local radiation.

cheerio.

Popeye
08-21-2003, 08:32 AM
okeh. sounds like you got some good clues there.

check also that your cable is in good shape. typically, from my experience, leaky connectors are the culprits in poor signal; particularly sound is bad if many bad connectors have exposed shielding layer.

along with snow, getting a 'hatching', ie diagonal thin lines walking across the screen? this is also connectors picking up unwanted pollution.

finally one more hincky way to fix is to consider the length of you cable. as you know, 1/4 and 1/2 and 1 and 2 times wavelength make excellent antanae. try snipping off a little cable to find an odd length that aint happy place for local radiation.

cheerio.

Popeye
08-21-2003, 08:32 AM
okeh. sounds like you got some good clues there.

check also that your cable is in good shape. typically, from my experience, leaky connectors are the culprits in poor signal; particularly sound is bad if many bad connectors have exposed shielding layer.

along with snow, getting a 'hatching', ie diagonal thin lines walking across the screen? this is also connectors picking up unwanted pollution.

finally one more hincky way to fix is to consider the length of you cable. as you know, 1/4 and 1/2 and 1 and 2 times wavelength make excellent antanae. try snipping off a little cable to find an odd length that aint happy place for local radiation.

cheerio.

htom
08-21-2003, 01:46 PM
They can work, if you get the correct one and install it correctly.

Correct is "broadband", 30 MHz - 2+ GHz. Some of them are designed for boosting only VHF or only VHF+UHF; these will not work well in your application (umm, some cable systems don't use the spectrum beyond UHF, you might get by with one of those if you don't use a channel number higher than 69.) It used to be that the Radio Shack salesfolk would be able to tell you which you needed, but these days [shakes head].

Correctly installed is as close to the source as practical.

It's better to amplify the signal going into the 100' run than it is to amplify the "signal + collected noise" coming out of the 100' run.

Then proper division of the signal; it is better to use a single 1 to 4 divider than (say) a 1 to 3 followed by a 1 to 2. (It's probably better to use the 1 to 4 with a 75 Ohm stub than a 1 to 3.)

I'd start wtih a +10 dB amplifier before the initial 1-2 splitter, and see how that works. If it's not sufficient, take it back and exchange it for a +20 or +25 dB amplifier installed there.

(If the picture and sound on the other end of that initial 1-2 split is currently ok, then install after the initial 1-2 splitter on the leg to the problem displays.)

htom
08-21-2003, 01:46 PM
They can work, if you get the correct one and install it correctly.

Correct is "broadband", 30 MHz - 2+ GHz. Some of them are designed for boosting only VHF or only VHF+UHF; these will not work well in your application (umm, some cable systems don't use the spectrum beyond UHF, you might get by with one of those if you don't use a channel number higher than 69.) It used to be that the Radio Shack salesfolk would be able to tell you which you needed, but these days [shakes head].

Correctly installed is as close to the source as practical.

It's better to amplify the signal going into the 100' run than it is to amplify the "signal + collected noise" coming out of the 100' run.

Then proper division of the signal; it is better to use a single 1 to 4 divider than (say) a 1 to 3 followed by a 1 to 2. (It's probably better to use the 1 to 4 with a 75 Ohm stub than a 1 to 3.)

I'd start wtih a +10 dB amplifier before the initial 1-2 splitter, and see how that works. If it's not sufficient, take it back and exchange it for a +20 or +25 dB amplifier installed there.

(If the picture and sound on the other end of that initial 1-2 split is currently ok, then install after the initial 1-2 splitter on the leg to the problem displays.)

htom
08-21-2003, 01:46 PM
They can work, if you get the correct one and install it correctly.

Correct is "broadband", 30 MHz - 2+ GHz. Some of them are designed for boosting only VHF or only VHF+UHF; these will not work well in your application (umm, some cable systems don't use the spectrum beyond UHF, you might get by with one of those if you don't use a channel number higher than 69.) It used to be that the Radio Shack salesfolk would be able to tell you which you needed, but these days [shakes head].

Correctly installed is as close to the source as practical.

It's better to amplify the signal going into the 100' run than it is to amplify the "signal + collected noise" coming out of the 100' run.

Then proper division of the signal; it is better to use a single 1 to 4 divider than (say) a 1 to 3 followed by a 1 to 2. (It's probably better to use the 1 to 4 with a 75 Ohm stub than a 1 to 3.)

I'd start wtih a +10 dB amplifier before the initial 1-2 splitter, and see how that works. If it's not sufficient, take it back and exchange it for a +20 or +25 dB amplifier installed there.

(If the picture and sound on the other end of that initial 1-2 split is currently ok, then install after the initial 1-2 splitter on the leg to the problem displays.)

paladin
08-21-2003, 01:55 PM
I would think that you have internal cable problems. Normally the signal from the cable will operate two or three tvs without degradation...and sometimes those same tv's plus an AM/FM stereo receiver.....and the folks above are correct...when you amplify the signalanywhere...at either end of the cable...you amplify the noise present along with the wanted signal. You might start disconnecting your system a cable at a time, both ends, to insure that you don't have a high impedance short on a cable...the signal should improve considerably if you do and new cables izz cheeeper than amplifiers and don't need to be plugged in...

paladin
08-21-2003, 01:55 PM
I would think that you have internal cable problems. Normally the signal from the cable will operate two or three tvs without degradation...and sometimes those same tv's plus an AM/FM stereo receiver.....and the folks above are correct...when you amplify the signalanywhere...at either end of the cable...you amplify the noise present along with the wanted signal. You might start disconnecting your system a cable at a time, both ends, to insure that you don't have a high impedance short on a cable...the signal should improve considerably if you do and new cables izz cheeeper than amplifiers and don't need to be plugged in...

paladin
08-21-2003, 01:55 PM
I would think that you have internal cable problems. Normally the signal from the cable will operate two or three tvs without degradation...and sometimes those same tv's plus an AM/FM stereo receiver.....and the folks above are correct...when you amplify the signalanywhere...at either end of the cable...you amplify the noise present along with the wanted signal. You might start disconnecting your system a cable at a time, both ends, to insure that you don't have a high impedance short on a cable...the signal should improve considerably if you do and new cables izz cheeeper than amplifiers and don't need to be plugged in...

cs
08-21-2003, 02:13 PM
That was my first thought, that it was internal. I've checked most of my connections and still the signal strength comes and goes. We've always had just okay cable (the stallite picture is much better) and here lately it has gotten worse. We live in an older neighborhood that don't get the high end service that other areas do.

I've thought about the broadband boosters but they run over $50. If it comes to that I will call the cable company again and see if there is not something that they can do.

Chad

cs
08-21-2003, 02:13 PM
That was my first thought, that it was internal. I've checked most of my connections and still the signal strength comes and goes. We've always had just okay cable (the stallite picture is much better) and here lately it has gotten worse. We live in an older neighborhood that don't get the high end service that other areas do.

I've thought about the broadband boosters but they run over $50. If it comes to that I will call the cable company again and see if there is not something that they can do.

Chad

cs
08-21-2003, 02:13 PM
That was my first thought, that it was internal. I've checked most of my connections and still the signal strength comes and goes. We've always had just okay cable (the stallite picture is much better) and here lately it has gotten worse. We live in an older neighborhood that don't get the high end service that other areas do.

I've thought about the broadband boosters but they run over $50. If it comes to that I will call the cable company again and see if there is not something that they can do.

Chad

Popeye
08-22-2003, 07:33 AM
A "short" is low impedance, 0 ohms, ie two wires touching or one wire touching ground. Very high impedance is an "open circuit"

almost correct...

a short is a connection to gnd, zero resistance. an open circuit means no connection. high impedence means there is a load on the circuit.

resistance and impedence are different animals. there will be a test in the morning so bone up.

Popeye
08-22-2003, 07:33 AM
A "short" is low impedance, 0 ohms, ie two wires touching or one wire touching ground. Very high impedance is an "open circuit"

almost correct...

a short is a connection to gnd, zero resistance. an open circuit means no connection. high impedence means there is a load on the circuit.

resistance and impedence are different animals. there will be a test in the morning so bone up.

Popeye
08-22-2003, 07:33 AM
A "short" is low impedance, 0 ohms, ie two wires touching or one wire touching ground. Very high impedance is an "open circuit"

almost correct...

a short is a connection to gnd, zero resistance. an open circuit means no connection. high impedence means there is a load on the circuit.

resistance and impedence are different animals. there will be a test in the morning so bone up.