What is the Linx’s Ringer Equivalence Number (REN)?

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Re: What is the Linx’s Ringer Equivalence Number (REN)?

Post by parity_bit » Sat Jul 06, 2013 11:41 pm

I think the OP, like I was, is confused about the nature of the Linx.

Ooma states that it is a DECT6 device and so that may be part of their confusion. Murphy's obviously correct because the Linx doesn't have a REN which is only used for inside wiring and the Linx doesn't make use of that. The phone jack on the Linx is not to be plugged into a phone jack but is instead to provide the fax/home security/wireless phone base with an RJ11 cord from the Linx to it. The Linx does not feed off the home phone wiring and then distribute a DECT signal to a base unit as someone could misunderstand. It instead communicates as a DECT client to the Telo and then distributes the phone signal to the cord.

Telo}}}}}}Linx----wire---->Wireless phone base using DECT)))))))))handset extensions.

Sorry for my crude representation. lol

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Bobby B
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Re: What is the Linx’s Ringer Equivalence Number (REN)?

Post by Bobby B » Wed Jul 17, 2013 4:14 pm

The Linx REN is 1. Note that most modern phone devices have a REN much less than 1. For example, my panasonic cordless phone has a REN of .1.
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Re: What is the Linx’s Ringer Equivalence Number (REN)?

Post by MLXXXp » Thu Jul 18, 2013 6:35 am

Bobby B wrote:The Linx REN is 1.
But note that although the Linx can provide current equivalent to REN 1, its voltage output when sending a ring signal is lower than a standard POTS line. The same goes for the Telo. Therefore, the Linx and Telo can have problems making certain phones ring, even though these phones ring fine on other systems.

I measured the ring signal voltage of a Linx, two Telos, and a Bell Canada POTS line, with my multimeter. The POTS line was about 85 VAC. The Linx and Telos were all about 55 VAC. Note that my meter does not read true RMS so it's only truly accurate for a sin wave. If the outputs were something other than a sin wave, its difficult to know what the actual peak voltages were but in any case, the Linx and Telos were quite a bit lower than the POTS line.

I took measurements with no phones plugged in and also with the line fairly heavily loaded with multiple phones, including an old Contempra phone with an actual mechanical bell ringer. The voltages didn't change significantly with or without a load, indicating that all systems were capable of supplying adequate current.

I've personally come across two phones where the lower ring voltages provided by Ooma equipment caused a problem:

- An old Northern Telecom Unity II phone. This phone has a neon lamp that flashes when the phone rings, to provide a visual ringing indication. Presumably this lamp uses the ring voltage directly to cause it to light. Although the phone would ring fine, audibly, the lamp would not flash with the Ooma devices.

- A Casio electronic phone. This phone does not have a high REN but requires a ring voltage higher than what the Linx and Telo provide. It doesn't ring at all with Ooma (but works fine for dialing out or if answered).

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