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Maximum distance from Cable modem to telephone

Frequent Visitor

Maximum distance from Cable modem to telephone

I just spent an hour and a half on chat with five different people. They are all quite friendly and nice, but woefully unprepared to review equipment or installation specifications. 


Simply stated; this is my situation and I need to know Comcast Installation Standards/Instructions
or Equipment Manufacturer specifications for maximum telephone wire length?


1) My cable modem is quite a distance from my main telephone console. (Approx 50 - 75 ft.)

     A) It is impractical to relocate equipment more closely together.

2) The standard internal telephone wire - twisted ribbon, usually equivalent to 28 or 26 gauge solid copper - has some issues with distance and interference.

     A) I may be able to use CAT 5, 26 Ga, Twisted Pair wire; but it is not practical at this time.


3) Assuming I can route the wire along a path that has zero to minimum external RFI interference 
how far can I go before the modem has problems with signal quality?


4) What are the standards used by Xfinity Installation teams regarding telephone wire length?


     A) I have a TECHNICOLOR tc8305c modem.


Any accurate assistance would be greatly appreciated.


Thank you in advance and wishing all a joyous Holiday season.



Problem Solver

Re: Maximum distance from Cable modem to telephone

I have gone to Builders Square or Lowes and bought over 50 feet of standard  phone wire with connectors and have used it successfully with my Comcast gateway and eMTA. The only caveat to this is if you are using that line for faxing you need to use 2 conductor phone wire otherwise no problems.

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