[Asterisk-Users] Vonage, PSTN, 911, and hardware question

[Shane Young]

Quoting Rajeev Sharma <rajeev at hoojamomma.com>:

*snip*
> 2. Phone availibility during a power outage is a big concern. I'm planning on keeping my regular
> 
> PSTN line around for emergencies and 911 dialing (so that 911 calls actually go to the 911
> center, 
> along with my address). Is there an easy way for all the phone jacks in my house to automatically
> be 
> switched to the PSTN line if my broadband goes out?

Using a double-pole-double-throw releay will do the trick for a single phone/line.

Viking makes a power fail transfer device (commonly built-in to many PBX's).

http://www.vikingelectronics.com/products/telephonemanagement/pf-6a(dbb).html

The PF-6A power failure bypass system makes it possible to receive calls during phone system and 
power outages. The PF-6A bypass unit connects 6 pre-assigned single line station phones directly to 
user-assigned C.O. trunks.