Sanyo VL-2300 - Manual (Page 220)

208 Section 3A: Sprint PCS Service Features – The Basics
To respond to an incoming call when Answer on Hold is activated:
ᮣ Press (or press Options [right softkey], highlight
Flash, and press ).
(The Answer on Hold will be automatically deactivated.
See page 32 for Answer on Hold.)
To switch back to the first caller:
ᮣ Press again (or press Options [right softkey],
highlight Flash and press ).
Tip: For those calls where you don’t want to be interrupted, you can
temporarily disable Call Waiting by pressing before
placing your call. Call Waiting is automatically reactivated once you end the
call.