|reply to scanman1 |
Re: Automatic Phone-Line Switch for SAT Box CallerID &2 line ATA
If the LAN port of your ATA is available, you should be able to connect another ATA there. I don't know whether the 1005 can be set as a bridge (rather than a router), but even if not, double NAT should not be a problem for a device registered to VoIP.ms.
If you really want to do this in homebrew hardware, IMO a simple way is with a DPDT relay, which when operated, would switch the PVR from the primary to the secondary line. If you steal power from the ATA's adapter to operate the relay, a 12 volt coil would be suitable. Have the secondary line's ringing voltage charge a capacitor, e.g. half-wave doubler configuration, with a voltage divider driving the base (or gate) of a transistor that controls the relay. Set the time constant so the relay stays operated for a couple of seconds after ringing stops, so the caller ID signal will pass. One minor shortcoming of this approach is that if you are on the primary line when a call comes in on the secondary, you will likely hear a "pop" when ringing stops and the relay reconnects the PVR to the primary line.