I have Call waiting. The door bell at the main door of my apartment building rings through the phone.
When I'm on the phone I can hear the beep for call waitng when the door bell is rung but don't know how to switch lines.
My phone is an ASTRA 390
On the Astra 390 while on the phone, one of the soft keys (ones that change function beside the LCD screen) should read "flash". Pressing that while on the phone should hold the one call, and switch you to the new incoming front door call. Once on the door call, I believe it's press "9" to trip the door switch. You can then use the "flash" button to get back to the first call.
I hope this helps.
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