old rotary phone vs. fiber optic phone lines

Will my old rotary phone work with the new fiber optic phone lines? The current copper phone lines carry current to power my old phone, so it works even when the power is out.

Do the new fiber optic lines carry power, or just information? I can’t see how the fiber optic lines could transfer any/enough electricity to power an old phone. Basically, it’s just a glass tube that light goes through, right?

Currently, it’s great to have a phone to use when the power goes out, since we do not get cellphone reception at my house, currently. And hell, I like using my old phone with the giant handset better than the new cordless ones with tiny handsets.

The phone company has installed the lines to, and the box at, my house; I am currently waiting for the final conversion any day now. Will my old phone work on that day?

It depends what you mean by “the new fiber optic phone lines.” If you’re referring to a fiber-to-the-premises service like FiOS, then the fiber terminates at a an optical network terminal in your basement and the ONT provides power to the ordinary copper twisted pair in your house which you can plug your phone into. Your phone won’t know the difference. I believe the switches still support pulse dialing.

If you’re referring to a VoIP solution deployed over something like Ethernet, then those require proprietary handsets which do not receive power from the network.

Fiber optic lines won’t carry power.

We were looking into some bundle through ATT with their ATT U-verse Voice. They stated that the new phone would not work during a power outage without battery backup power.

That’s true. The ONT plugs into your house’s power in order to energize your copper twisted-pair. So your handset gets power from your house rather than the phone company’s CO. When I got FiOS at my last place they provided a nice beefy UPS to go with it, though.

For what it’s worth, my 1963 Bell System black rotary desktop phone works just fine when plugged into my cable modem.

As it would be expected. But the cable modem is the device powering the phone, not the fiber optic source. It’s just converting whatever signal(s) it receives and sending them to your phone.
Without a source of power to the cable modem it would not be able to supply voltage to the phone.

ZenBeam is right (not quite right *) - Fiber optic lines do not carry electric voltage to the customer. That requires a conductor like copper or aluminum wires.

So some device, either close to your house or in your house, must convert the laser signals to electricity (electric signals for the cable, electric power and signals for the phone, electric signals for the internet connection)

In order for your phone to continue working when the power goes out you would need a backup source of power for your modem and possibly the base station of your phone if it’s cordless. You might also be at the whim of the backup capabilities of the cable company. If they relied on the local power grid to operate repeaters or switching then your phone may not work during an outage even though all of the devices in your control are powered.

*Nitpick - there is power in a laser pulse, but not enough to convert to electricity for your phone.

The answer depends on exactly what you’re converting to, as friedo indicated.

Generally, your old phone should still work, as Telcordia standards require backwards compatibility. How your old phone will continue to work depends on whether you’re talking about converting to FiOS, VOIP (like Vontage), or if your carrier is just bringing fiber to the curb.

Related question: Does FiOS have to follow the Rule of Five Nines?

I don’t know about Verizon and Fios, but I have AT&T Uverse here, which is a fiber to the node / neighborhood system where the “last mile” is a standard twisted pair delivering VDSL. Where Fios has an ONT, Uverse has a Residential Gateway or RG. Just different names for essentially the same box - bits go in and television and VOIP voice lines go out. the VOIP lines are “POTS-ified” so normal analog (Plain Old Telephone Service) phones can be used.

AT&T provides a UPS that is claimed to be able to power the RG for up to four hours, so we’ll have voice service to last through most power outages.

The Big IF though, is your phones. Plain old touch tone phones work fine on Uverse. Rotary dial phones do NOT work. They will ring and can answer calls, but they will not dial out. The RG simply can not translate pulse dialing. I have no idea if Fios is the same way.

Verizon FIOS comes with a battery backup, so wired phones work. But the battery only works for a few hours. When we had a snowstorm in October we were without power for 58 hours and without phone service for about 50 of those hours.

it makes sense to have lots of battery backup and/or turn on phones only to make outgoing calls.

It’s not really a matter of “turning on” phones - a standard desk phone has no on/off switch to begin with. It takes very little power to operate one - a standard ringer will draw about 750 milliwatts, and when off-hook, a phone pulls under 150 milliwatts from the phone line.

Not much power is needed to run the ONT or RG, so it’s mostly a matter of how long a UPS will run on battery with minimal load. Some can only run 15 minutes and some can run a small handful of hours, but none will run indefinitely.

Depends on the box; some VOIP and other implementations do not allow pulse dialing. If you have fibre to your basement, there is a powered box there (plugged into household power) that converts the data signal into POTS (plain old telephone service). Then, your plain-old standard 2-wire telephone runs off that. I have seen some implementations that allow pulse, and many that did not.

I worked with a CISCO box once that allowed up to 48 plain phones to be connected, but they had to be touch-tone. (Businesses need something like this, even for VoIP, if they have faxes, for example). The odd thing about this - the old phones had IIRC 96V pulse ringing; the new standard was just the 48V. So there was not enough power to ring the electromechanical hammer-hits-bell unless you turned the phone sideways so the hammer had a gravity assist.

In areas with still the standard telephone wire service, the wires go back to a central switch which has the same issues - some may not support pulse dialing, but this is fairly rare. Then they piggyback DSL service over these wires on top of the voice signal.