RJ11 maximum length

[marger]

We have a modem and telephone connected to a mainline(with splitter) using a 1 meter RJ11 cable each. We want to transfer the modem to another offich which is more or less 25 meters away from our mainline(with splitter). Can we extend the length of the cable (RJ11) to 25 meters? or there is another way or correct solution for this problem?

 

[noriel]

Some recommends 15m only.. but others are running it on 25-30 and have no problem... just try it 😀

 

[Solandri]

Phone service is much less demanding than ethernet. RJ11 (cat 3) cable will work out to a dozen kilometers or more. Even DSL (which uses higher frequencies than voice) will work out to several km (ADSL), unless you're using one of the higher-speed variants like VDSL2. And even those are still good to several hundred meters before they start dropping in bandwidth (they reach ADSL speeds at about a km or two).

If you encounter problems with a mere 25 meter extension, try a different cable. The flat ones in particular separate the pairs for phone line 2, so will pick up more noise (assuming you're using phone line 2). The rounded type of cable is best, as those keep the twisted pairs twisted. If you still have problems, check your connectors and/or couplers, or if you have the equipment try re-crimping the plugs.

Just be sure you use DSL filters on any other devices connected to the same phone line with your splitter. As I said, DSL operates at higher frequencies than voice, so the extra devices may add noise to the line which interferes with the DSL service, even though you can't hear any noise during a phone call. The filters are a bandpass filter which specifically blocks out signals at the frequencies used by DSL.

 

[mbarnes86]

Hi
Do you mean broadband modem or old fashioned v90 modem running at 40 to 56 kb or FAX modem?

Or broadband modem, router, switch + wireless access point

Long rj11 cables slow down broadband speed especially if run near mains cables or devices

Rj45 ethernet cable on cat 5 or cat 6 can run upto 100 meters depending on speed of 10/100/1000

Regards
Mike Barnes