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No phone during power outage

Regular Contributor

No phone during power outage

Hi All,

 

My power does not go out too often but I noticed a slight issue.  The last time a comcast tech was over my house he installed some kind of signal booster that is powered.  The coax come from the outside of my house to the bottom of the power supply.  I have found that when this power supply gets unplugged all service stops working, incudling voice.

 

I am assuming this should not be the case?  Can anyone elaborate what this may be and why my phone is tied into this?  When I unplug my modem and my house still has power I can still make calls but when this signal booster looses power all bets are off.

Cable Expert

Re: No phone during power outage

In most installations, the eMTA telephony modem is split off the line coming into the home before the drop amp.  Ususally the drop amp is for compensating for splitter loss to feed multiple TV outlets in the home and best practice is not to amp the cable modem or telephony modem, but this depends on the signal level coming into the home.

 

Most installers would split off the line to the modem with a 2way splitter before feeding the amp, as in most locations the signal level off the 2way would be enough to drive the modem or telephony modem.

 

Your signal levels should be checked and your line to the modem should be rewired to run right off a 2way splitter keeping the amp dependent only for the TV outlets in the home.  What you have was not done to best practices in how the home was wired.




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Regular Contributor

Re: No phone during power outage

Thanks for the info.  When the installer was out they put up a new grey box behind all of my incoming coax so it does not look like I can access it anymore - is this the case?  I guess I have to have a technician come out?

 

Also, for the heck of it I opened up the customer section of my voice copper coming from the phone office on the side of my house and it looked like comcast cut the copper to where it gets spliced out in the telephone network device box.  Is this normal practice too or should comcast have not cut my copper?

Cable Expert

Re: No phone during power outage

In order to backfeed the dial tone voltage to the inside wiring, the connection to the telco needs to be disconnected.  That is done in the network interface box and is normal when CDV is installed.

 

If this was a recent installation, it would be best to get the tech back out and wire up the modem properly so it is not dependent on the drop amp.  You might need to make a point that it was not done right the first time so you don't get charged.  If you do get charged you will need to argue the charge to get it removed.




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Regular Contributor

Re: No phone during power outage

Thanks for the info! What happens if I ever want to go back to regular copper voice, is this possible?

 

A side question ... Does comcast have their own exchange like the local verizon offices do or is VoIP just acting as a bridge between comcast and verizon?