If an inbound PSTN call is answered by a PSTN phone, can the OBI phone join the call?
The short answer is no.
The OBi device will not "interfere" with the LINE if it detects that someone is using it with another phone. The "Join" (some people call it "Barge In") feature is not available on the OBi110.
Can I pick up the phone and press # to join the PSTN call in progress?
No. If the line is already in use, dialing # would result in an error signal. I guess "barge-in" would be a reasonable feature to request.
Hmm, the detection by the Obi unit that the line is in use is done by sensing line voltage I believe. Could we not find a setting to change this so that the Obi never detects a "line in use" condition?
Just asking if anyone knows how this can be done... or not.
The inability to join a conversation in the house would seem to be a significant drawback.
You are aware that there's a "LineInUseVoltageThreshold" setting and a "LineInUseCurrentThreshold" setting under Physical Interfaces, LINE Port, Port Settings, right?
If you set the voltage one to some ridiculously low figure (like maybe one or two volts) it might never detect a normal in-use condition. Worth a try, maybe.
MichiganTel, you're very smart.
Yes, normally the PSTN line will drop to around 6-10V when in use.
Thus, setting it to 2V will always fool the OBi to think it is on hook.
So, from the phone, press # to join the conversation on the PSTN line.
Well, just don't forget there's a potential drawback to that method — if you are on a call using a phone not connected to the OBi110 and someone else tries to initiate a call from another service (SP1, SP2, OBiTALK network, or even from the phone connected to the OBi110 Phone port by dialing **8 plus the number), the OBi110 will not detect the line in use condition and will blast out a series of touch tones in your ear and then connect that caller into your conversation. If you don't allow any other services to access the Line port and don't use **8 to place calls from the phone connected to the OBi110 (but instead always use # to get dial tone) it probably won't be an issue, but it's something to be aware of.
So, ultimately, an actual "barge in" feature (that doesn't require changing the "LineInUseVoltageThreshold" setting, and only works from the phone connected to the phone port, and requires a configuration option to be set that allows it) might not be such a bad idea. But in the meantime, for many users, changing that setting will work well enough.
Yep, that works. I set LineInUseVoltageThreshold" and "LineInUseCurrentThreshold" to 2 volts and no problem. For now, I'll accept that on rare occasion the Obi will knock someone else off line. To be able to pick up an ongoing call is much more important. I think it would be great to have a setting on the dashboard to set this (with a good explanation)
To follow up, this setting does not work well, as the OBi does not recognize when an extension is picked up first and keeps on ringing.
I've now set "LineInUseVoltageThreshold" back to the default 25 which SHOULD allow the OBi to recognize an extension being picked up when it is On Hook. We'll see.