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  1. Member
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    Channel 5.1 (Fox) comes in on the TV closest to the splitter, and doesn't come in on the basement TV. But, 7.1 (ABC, I think) comes in on the basement TV and not on the TV closest to the splitter!

    I have an indoor antenna leading to a Phillips amplifier, leading to a splitter, and then cables leading to both TVs. Why would the basement TV not even register 5.1, but get great reception in a channel that the TV closest to the antenna barely receives?

    A little extra, cool information.

    I didn't want to run coaxial cable to the basement, so I spliced the cable to CAT5 (I previously wired my house with CAT5) and plugged it in upstairs, then spiced another coaxial to CAT5 and plugged it in downstairs and to the TV.

    So the basement TV's signal is going through about 20 feet of unshielded wire! (I'm just psyched that it worked at all).

    Still confused? Here's the order: TV 1; Antenna, amp, splitter, TV
    TV2; Antenna, amp, splitter, coaxial spliced to CAT5 going into wall port, CAT5 spliced to coaxial coming out of wall port, TV

    TV1 gets channels 5.1, 9.1, and a bunch of analog
    TV2 gets channels 7.1, 9.1, and a bunch of analog

    why oh why????
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  2. Banned
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    I'd guess you're pulling different channels because the TVs have different tuners. Considering that you're using a cheap, overpowered amp that's pushing the AGC circuits on your monitors (expect a shorter lifespan for both sets) -- as well as inappropriate 100ohm CAT5 stranded-core high-capacitance/high-impedance twisted-pair conductors instead of 75-ohm coax, and have hand-hewn splices (and maybe even solder or connectors that use it) -- I'm not at all surprised that you get a picture. Why waste your dough on ACT5: RadioShack makes some ridiculously cheap 26-g hookup wire that might even help you pick up a few more channels. But please....I'll pass on having a look. There's enough dumbed-down junk on tv without watching it via the horrible images you're getting.
    Last edited by sanlyn; 23rd Mar 2014 at 08:02.
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  3. Member
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    Originally Posted by sanlyn View Post
    I'd guess you're pulling different channels because the TVs have different tuners. Considering that you're using a cheap, overpowered amp that's pushing the AGC circuits on your monitors (expect a shorter lifespan for both sets) -- as well as inappropriate 100ohm CAT5 stranded-core high-capacitance/high-impedance twisted-pair conductors instead of 75-ohm coax, and have hand-hewn splices (and maybe even solder or connectors that use it) -- I'm not at all surprised that you get a picture. Why waste your dough on ACT5: RadioShack makes some ridiculously cheap 26-g hookup wire that might even help you pick up a few more channels. But please....I'll pass on having a look. There's enough dumbed-down junk on tv without watching it via the horrible images you're getting.
    I totally don't know what I'm doing. All I know is that the little 1's and 0's go through the metal thing and that Coaxial has a central and an outer metal thing, so I figured that splicing to a wire that goes through my house would be better than running 30 feet of extra cable. I did solder the connectors.
    Didn't we used to run bare copper wire from our rooftop antennas to our tv sets way back in the day?

    All that said . . . I didn't understand half of what you said. I picked out that it could be because of the tuners in my TV, one may be better? And now I'm frightened that I'm killing my tv's (The whole thing or just the tuner by the way?) because of the evil ohms that are attacking them?!?!!
    Oh, and the images aren't horrible, they are crystal clear. It's just the one channel upstairs is really choppy, and the other channel downstairs doesn't exist
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    I don't know if the two tuners are "better". Just different. Anyway, enjoy.
    Last edited by sanlyn; 23rd Mar 2014 at 08:02.
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  5. "Dumbed down version"

    First of all, tuners are not equal, meaning it is possible that each tuner will pickup different stations.

    Coaxial cable is recommended because it cuts down on or eliminates interference.

    For OTA, it is better not to use splitters, use low powered distribution amp(s).
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    Originally Posted by verbakint75 View Post
    Channel 5.1 (Fox) comes in on the TV closest to the splitter, and doesn't come in on the basement TV. But, 7.1 (ABC, I think) comes in on the basement TV and not on the TV closest to the splitter!

    I have an indoor antenna leading to a Phillips amplifier, leading to a splitter, and then cables leading to both TVs. Why would the basement TV not even register 5.1, but get great reception in a channel that the TV closest to the antenna barely receives?

    A little extra, cool information.

    I didn't want to run coaxial cable to the basement, so I spliced the cable to CAT5 (I previously wired my house with CAT5) and plugged it in upstairs, then spiced another coaxial to CAT5 and plugged it in downstairs and to the TV.

    So the basement TV's signal is going through about 20 feet of unshielded wire! (I'm just psyched that it worked at all).

    Still confused? Here's the order: TV 1; Antenna, amp, splitter, TV
    TV2; Antenna, amp, splitter, coaxial spliced to CAT5 going into wall port, CAT5 spliced to coaxial coming out of wall port, TV

    TV1 gets channels 5.1, 9.1, and a bunch of analog
    TV2 gets channels 7.1, 9.1, and a bunch of analog

    why oh why????
    The TVs have different tuners and that may be part of the problem, but signal strength can play a role as well.

    An overly strong signal can overwhelm a digital tuner. I have seen it myself. If a channel is very strong, and you are amplifying it, the TV closest to the source could be receiving a signal that is too strong to tune, and the TV furthest away may be receiving a signal that has become weak enough to tune.

    Conversely if one signal is very weak, the TV closest to the amplifier may be receiving an adequate signal, but the TV that is furthest away may be receiving a signal that has become too weak to tune.

    I would agree that CAT5 isn't a good substitute for RG6 coax with adequate shielding.
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    As sanlyn says, there's an impedance mismatch. TV coax is 75 ohms while CAT 5 is rated at 100 ohms.

    Having a mismatch will lead to signal 'reflections' and can cause some frequency ranges on the cable to be significantly reduced (while other frequencies might remain unaffected). I'm not sure if this would cause different frequency ranges along different runs of cables (after the split point) to be affected. Maybe if the cable lengths after the split are different lengths...

    I don't know much about this - only that what you're doing is a baaad idea

    In addition to the cable type mismatch, you need to be careful how you split the cable. A powered amplifier/splitter should be used to avoid any drop in signal strength. Just splitting the cable (without using either a passive or powered device) can itself cause reflections.
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  8. Member
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    The setup described could result in a filter being created. It is possible to design RF filters that use specific lengths and impedance of cable. Back in the twin lead era filters for the FM band could be make with a specific length of twin lead.
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  9. Loster is absolutely right, when it comes to RF things can get incredibly complex. Materials used, distances between conductors, dipoles and reflectors can all cause strange behaviours. The complexity rises with every components you add to your RF circuit.

    If you want to distribute an RF signal, you gotta do it right. Start with a decent antenna, indoors are only good close to the transmitter (10 miles). Get an outdoor antenna and install it away from obstacles (that includes trees, leaves block UHF waves). If you can't get a good signal you'll have to move it around and up/down to try and catch a reflection.

    Use RG6 95% shielding cable to bring the signal to the TV's going through a distribution amplifier (drop amp; try to get one with exact number of ports for your needs).

    This is an inexpensive antenna that gives good results, it's not too big, has a wide aperture and good signal gain: http://www.digiwavetechnologies.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=278

    Here's a 4 port drop amp: http://www.digiwavetechnologies.com/index.php?module=pagemaster&PAGE_user_op=view_page...on=162:126:159

    If you want better quality, look for Channel Master products.

    Go to TVfool to see what stations you could get in your area, the map is handy to help pointing the antenna in the right direction.
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  10. Member
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    Thanks for all the great replies!
    As I learn more about this I know more about what to look for, and it turns out my house's coaxial cable config was designed beautifully. I went outside and saw a six way splitter, so all those coaxial cables in the house (that I thought were daisy-chained) are actually all coming straight from the source. So really all I have to do is place an antenna on the roof above the cable box, locate which cables head to the TV's and connect them there.

    Thanks again for all the help
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    You'll have a cleaner picture with coax, and you won't have to drive your tv with a cheap amp. Believe me, they might have a "sharp" picture (more or less), but they're noisy and unreliable. The antenna itself is another issue altogether. I got rid of mine many years ago.
    Last edited by sanlyn; 23rd Mar 2014 at 08:03.
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  12. Member lacywest's Avatar
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    Originally Posted by nic2k4 View Post
    Loster is absolutely right, when it comes to RF things can get incredibly complex. Materials used, distances between conductors, dipoles and reflectors can all cause strange behaviours. The complexity rises with every components you add to your RF circuit.

    If you want to distribute an RF signal, you gotta do it right. Start with a decent antenna, indoors are only good close to the transmitter (10 miles). Get an outdoor antenna and install it away from obstacles (that includes trees, leaves block UHF waves). If you can't get a good signal you'll have to move it around and up/down to try and catch a reflection.

    Use RG6 95% shielding cable to bring the signal to the TV's going through a distribution amplifier (drop amp; try to get one with exact number of ports for your needs).

    This is an inexpensive antenna that gives good results, it's not too big, has a wide aperture and good signal gain: http://www.digiwavetechnologies.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=278

    Here's a 4 port drop amp: http://www.digiwavetechnologies.com/index.php?module=pagemaster&PAGE_user_op=view_page...on=162:126:159

    If you want better quality, look for Channel Master products.

    Go to TVfool to see what stations you could get in your area, the map is handy to help pointing the antenna in the right direction.
    I looked at the links ... where are the prices ... the antenna shown is similar to the one I have mounted on my chimney ... before mounting it ... I re-enforced all the areas with extra plastic [I took a part a note book binder and used the plastic] just in case the thin plastic the antenna used for insulators ... disintegrated and then used extra black electrical tape to keep everything solid and then I mounted it on a 10 foot pole on my chimney. It's been there since 2006 ... but one of the elements on the very top is bent down ... a frikkin crow must have sat on it and bent it ... taking off ...
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  13. Member Cornucopia's Avatar
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    BTW, "back in the day" there was NEVER a time when running bare copper wire was a good thing, either technologically or for safety reasons.

    Scott
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  14. Member Trippedout's Avatar
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    wired in series the tunners will interfere with each transceiver or receiver a simple antenna switch or junction box at antenna employing diode inline to allow only one way traffic a preamp is not a good idea they amplfy the signal
    which if you have a bad reception your amplifying a bad reception as for rf that is more prevalent in a transceiver where rf can be run to ground a good ground rod in ground with as short as possible ground wire ferrite rings can be used to
    stop rf runing up or down the cable then theres emf that a hole other subject main rule for modern marconi inspired antennas is as high as possible in the clear make sure you haven't got them wired in series looping the circuit
    I don't use an antenna for tv I use sat dish not needing height so easy to access and maintain simply got to love freesat got one my fav words at begining and with multiple outputs from lnb no hassles come along way since amateur bouncing
    signals of satellites to send slow scan tv
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  15. Originally Posted by lacywest View Post
    I looked at the links ... where are the prices ...
    That's from the manufacturer's site, Digiwave is common and can be found all over the country. The plastic hangers seem to be made of ABS and should be pretty resilient. They have another antenna that uses a stamped piece of metal for the dipoles, that should keep it from getting bent by birds.
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