[Asterisk-Users] Switch between calls without initiating a threeway converstaion

[Paul Crick]

> I was just wondering if there was a way that you could
> have two calls on one line and switch between the two
> without initiating a threeway conversation? I would
> imagine that Flash is the way to do this, but when I
> Flash twice, a 3-way call is initiated.
It's a tricky one isn't it.. There were changes to the way this worked in
the UK a couple of years back which made it easier for people to use at the
cost of lost functionality.

It used to be that you made a call, flashed, made another call. If you
flashed again you got dialtone and could press 1 to end the current call and
revert to the other one, 2 to toggle between the two calls, or 3 to join
them in a 3 way call. The same held true for call waiting - hear the beep
and press flash then 0 to reject the call and turn off call waiting for the
rest of the call, press 1 to end the current call and answer the new
incoming call, or press 2 to switch between them. In both these scenarious
you could do flash then 2 as many times as you wanted.

In a call waiting scenario it gets confusing if the inbound call hungup just
before you hit flash. The exchange knows the call's gone away, and thinks
you want to do a consultative or three way call. It gives you dial tone
inviting dialing of a number. Meanwhile, you're thinking you're in "command
mode" and issue a single digit to toggle to the new call. The exchange waits
for more digits, it thinks you're dialling a phone number.. confusion
ensues!

To stop the madness, they made it work more like it does in North America
where it's all about the flash hook and little else.

Back to your problem then.. hmm.. You could probably hack the code round a
bit to give you the functionality you want for Zap attached devices, but I
wonder how it all works with external boxes like ATA-186s.. it sees the
flash hook and starts issuing SIP messages for 3 way calling and stuff? I
bow to the greater knowledge on the list there - maybe someone can shed some
light?

> Also, is it possible to hang up one of the calls, and
> then continue talking to the second call?
Yes, this should work - the held call should recall back to you, making your
phone ring.

Cheers
Paul