Splicing an HD antenna into my Comcast cable coax - Blu-ray Forum

jc480 · 04-22-2009, 04:13 PM

I have Comcast basic cable. I'm sick of paying for what I can get free over the air.

I also receive Comcast internet service on my cable.

I wish to replace Comcast with an HD antenna...I have a few questions that I hope some of you can answer

- I have a powered signal booster in my attic where the coax comes into the house...should the signal booster be upstream or downstream from the HD antenna?
- I want to turn off Comcast cable AFTER I splice the antenna into my incoming coax line. What will I see at my television when I have Comcast basic cable and a signal from an HD antenna coming on the same coaxial cable?
- Will there be any issues with an HD antenna signal interfering with my Comcast internet as they will both be using the same coax?

Thank you!

mtbkr · 04-22-2009, 09:59 PM

for starters, i am a comcast supervisor. if you splice the antenna into the cable it can cause upstream noise to be back fed into the cable and then this noise will be amplified by the booster in your attic. this noise can kill your internet and if the noise is bad enough it can cause a internet and phone outage in your node. second, the tech that hooked up that amp in your attic should have never ran your internet line through it, just the t.v signal. i would recommend that you do not try and run the cable and antenna at the same time. hook up your antenna to make sure it works the way you like. if it does then set up a appointment for a tech to come out and make sure that your internet has its own outlet(bypassing any splitters or the amp), then tel him you no longer want the video service and disconnect it.

mdabb · 04-22-2009, 10:10 PM

Get an A/B switch from Parts Express. That's What I use to switch back and forth between the cable and antenna feed. Another good thing to do is make sure you are using a proper amp, sometimes it can be too weak or too strong, yes too strong !!!

I use to know of a great "how to" antenna website, let me try to find it again.

mdabb · 04-22-2009, 10:27 PM

Here you go: http://www.hdtvprimer.com/ISSUES/erecting_antenna.html

Should have all the info anyone could possibly need to answer any questions you might have about the realm of antenna's.

mtbkr · 04-22-2009, 10:31 PM

if he is getting rid of his cable then no a/b switch is needed. 99% of the house amps i run into are garbage. if he already has the amp that comcast gave him then he will not need to buy a new one.

mdabb · 04-22-2009, 10:42 PM

Quote:

Originally Posted by mtbkr

if he is getting rid of his cable then no a/b switch is needed. 99% of the house amps i run into are garbage. if he already has the amp that comcast gave him then he will not need to buy a new one.

Overlooked the "getting rid of Comcast" part, sorry bout that. I don't blame him though !!!

Just depends on the amp that's all. I am not familiar with the Comcast supplied amp so I wouldn't know how well it will work in his situation. I will say not using the proper amp for whatever antenna setup he is going with can have a negative effect on the signal. He didn't specify what antenna he is going with, so no use in guessing.

mtbkr · 04-22-2009, 10:51 PM

+1...all depends on the antenna quality

jc480 · 04-23-2009, 01:42 AM

Thank you for the info, guys.

Here is the antenna I am using....it's going in my attic (homeowner's association won't allow external antennas)

Channel Master 4228HD

mtbkr · 04-23-2009, 03:20 PM

i would recommend that you use the preamp that they have paired with that antenna. the comcast amp may not pass "all" the frequencies it trying to pull in. have you decided whether or not your gettin rid of cable and keeping the internet or if your are going to try and tie it all in together. setup configurations can vary depending on this decision.

jc480 · 04-23-2009, 04:18 PM

mtbkr

Thanks for the heads up. I'm going to keep my Comcast basic internet but cancel the basic television service and replace it with this OTA antenna array.

mtbkr · 04-23-2009, 04:59 PM

i run into these type of situations ALOT at work. i would recommend that you have a service tech come out and reconfigure you internet outlet so that it is the ONLY cable hooked up. no splitters, no amps, just the grounding that needs to be done outside. then have him dx your tv service.

jc480 · 04-23-2009, 08:44 PM

Isn't there a splitter I could use that would block any potential signal from the antenna going UPSTREAM back through the splitter, through the cable and outside my house? i.e. it would only allow signals to travel one way----down to my audio components thus stopping the potential of a node outtage?

mtbkr · 04-24-2009, 05:21 AM

nope. no such splitter. your best bet in your situation would be to swap the cable signal out for the antenna. since you are getting rid of it anyway. i know it sucks to have a tech come out, but you also dont want to screw up your internet speeds. as a warning though i am giving you worst case sinario with all this upstream noise talk. its very possible that the antenna will not cause any noise at all, but i have been called out at 1 a.m for an outage because of these things MANY times. and we have to end up completely shutting all your service off because your house is killin the node. generally the digital signals on the antenna will cause no problems, its the analog frequencies that thing is picking up that interfere with the upstream spectrum.

jc480 · 04-24-2009, 11:53 AM

Thanks for the explanation. I hadn't considered the possibility that the antenna would actually broadcast the cable signal feed outside my home over the air...I can see that messing with people's TV & possibly radio receptions.

That would suck getting a visit from the local Sheriff with a fine in hand.

04-22-2009, 04:13 PM	#1
jc480 Power Member Member since:Nov 2008 Location:Detroit, MI Home Theater Gallery:28 4K collection:22 Blu-ray collection:747 DVD collection:10 Digital collection:882 Prime collection:2 Blu-ray reviews:15	Splicing an HD antenna into my Comcast cable coax I have Comcast basic cable. I'm sick of paying for what I can get free over the air. I also receive Comcast internet service on my cable. I wish to replace Comcast with an HD antenna...I have a few questions that I hope some of you can answer - I have a powered signal booster in my attic where the coax comes into the house...should the signal booster be upstream or downstream from the HD antenna? - I want to turn off Comcast cable AFTER I splice the antenna into my incoming coax line. What will I see at my television when I have Comcast basic cable and a signal from an HD antenna coming on the same coaxial cable? - Will there be any issues with an HD antenna signal interfering with my Comcast internet as they will both be using the same coax? Thank you!

04-23-2009, 01:42 AM	#8
jc480 Power Member Member since:Nov 2008 Location:Detroit, MI Home Theater Gallery:28 4K collection:22 Blu-ray collection:747 DVD collection:10 Digital collection:882 Prime collection:2 Blu-ray reviews:15	Thank you for the info, guys. Here is the antenna I am using....it's going in my attic (homeowner's association won't allow external antennas) Channel Master 4228HD Last edited by jc480; 04-23-2009 at 01:48 AM.

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04-22-2009, 09:59 PM	#2
mtbkr Active Member Member since:Apr 2009 Location:washington(state) Blu-ray collection:65	for starters, i am a comcast supervisor. if you splice the antenna into the cable it can cause upstream noise to be back fed into the cable and then this noise will be amplified by the booster in your attic. this noise can kill your internet and if the noise is bad enough it can cause a internet and phone outage in your node. second, the tech that hooked up that amp in your attic should have never ran your internet line through it, just the t.v signal. i would recommend that you do not try and run the cable and antenna at the same time. hook up your antenna to make sure it works the way you like. if it does then set up a appointment for a tech to come out and make sure that your internet has its own outlet(bypassing any splitters or the amp), then tel him you no longer want the video service and disconnect it.

04-22-2009, 10:10 PM	#3
mdabb Power Member Member since:Jan 2008 Trading Score:1	Get an A/B switch from Parts Express. That's What I use to switch back and forth between the cable and antenna feed. Another good thing to do is make sure you are using a proper amp, sometimes it can be too weak or too strong, yes too strong !!! I use to know of a great "how to" antenna website, let me try to find it again.

04-22-2009, 10:27 PM	#4
mdabb Power Member Member since:Jan 2008 Trading Score:1	Here you go: http://www.hdtvprimer.com/ISSUES/erecting_antenna.html Should have all the info anyone could possibly need to answer any questions you might have about the realm of antenna's.

04-22-2009, 10:31 PM	#5
mtbkr Active Member Member since:Apr 2009 Location:washington(state) Blu-ray collection:65	if he is getting rid of his cable then no a/b switch is needed. 99% of the house amps i run into are garbage. if he already has the amp that comcast gave him then he will not need to buy a new one.

04-22-2009, 10:51 PM	#7
mtbkr Active Member Member since:Apr 2009 Location:washington(state) Blu-ray collection:65	+1...all depends on the antenna quality

04-23-2009, 03:20 PM	#9
mtbkr Active Member Member since:Apr 2009 Location:washington(state) Blu-ray collection:65	i would recommend that you use the preamp that they have paired with that antenna. the comcast amp may not pass "all" the frequencies it trying to pull in. have you decided whether or not your gettin rid of cable and keeping the internet or if your are going to try and tie it all in together. setup configurations can vary depending on this decision.

04-23-2009, 04:18 PM	#10
jc480 Power Member Member since:Nov 2008 Location:Detroit, MI Home Theater Gallery:28 4K collection:22 Blu-ray collection:747 DVD collection:10 Digital collection:882 Prime collection:2 Blu-ray reviews:15	mtbkr Thanks for the heads up. I'm going to keep my Comcast basic internet but cancel the basic television service and replace it with this OTA antenna array.

04-23-2009, 04:59 PM	#11
mtbkr Active Member Member since:Apr 2009 Location:washington(state) Blu-ray collection:65	i run into these type of situations ALOT at work. i would recommend that you have a service tech come out and reconfigure you internet outlet so that it is the ONLY cable hooked up. no splitters, no amps, just the grounding that needs to be done outside. then have him dx your tv service.

04-23-2009, 08:44 PM	#12
jc480 Power Member Member since:Nov 2008 Location:Detroit, MI Home Theater Gallery:28 4K collection:22 Blu-ray collection:747 DVD collection:10 Digital collection:882 Prime collection:2 Blu-ray reviews:15	Isn't there a splitter I could use that would block any potential signal from the antenna going UPSTREAM back through the splitter, through the cable and outside my house? i.e. it would only allow signals to travel one way----down to my audio components thus stopping the potential of a node outtage?

04-24-2009, 05:21 AM	#13
mtbkr Active Member Member since:Apr 2009 Location:washington(state) Blu-ray collection:65	nope. no such splitter. your best bet in your situation would be to swap the cable signal out for the antenna. since you are getting rid of it anyway. i know it sucks to have a tech come out, but you also dont want to screw up your internet speeds. as a warning though i am giving you worst case sinario with all this upstream noise talk. its very possible that the antenna will not cause any noise at all, but i have been called out at 1 a.m for an outage because of these things MANY times. and we have to end up completely shutting all your service off because your house is killin the node. generally the digital signals on the antenna will cause no problems, its the analog frequencies that thing is picking up that interfere with the upstream spectrum.

04-24-2009, 11:53 AM	#14
jc480 Power Member Member since:Nov 2008 Location:Detroit, MI Home Theater Gallery:28 4K collection:22 Blu-ray collection:747 DVD collection:10 Digital collection:882 Prime collection:2 Blu-ray reviews:15	Thanks for the explanation. I hadn't considered the possibility that the antenna would actually broadcast the cable signal feed outside my home over the air...I can see that messing with people's TV & possibly radio receptions. That would suck getting a visit from the local Sheriff with a fine in hand.

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