If you have an analog phone set on your desk the following features are available ... While on an active call, press the "TRN/CNF" key (this will place the first call on hold and give you dial tone), ...
The mobile phone may ... by anything but a set of different tones. If you’ve ever encountered a mechanical exchange you’ll recognise the harsh-sounding low-frequency dial tone, and the various ...
One late night many decades ago, I chanced upon a technical description of the Touch-Tone system ... I bet I can dial the phone! I sprang out of bed and started pecking out a Basic program ...