Grandstream Networks HT503 User Manual page 33

"#". Wait for dial tone and hang up. (dial tone indicates successful forward)
*73 Cancel Unconditional Call Forward. To cancel "Unconditional Call Forward", dial "*73",
wait for dial tone, then hang up.
*78 Enable Do Not Disturb (DND): When enabled all incoming calls are rejected.
*79 Disable Do Not Disturb (DND): When disabled, incoming calls are accepted.
*87 Blind Transfer
*90 Busy Call Forward: Dial "*90" and then the forwarding number followed by "#". Wait
for dial tone then hang up.
*91 Cancel Busy Call Forward. To cancel "Busy Call Forward", dial "*91", wait for dial tone,
then hang up.
*92 Delayed Call Forward. Dial "*92" and then the forwarding number followed by "#". Wait
for dial tone then hang up.
*93 Cancel Delayed Call Forward. To cancel Delayed Call Forward, dial "*93", wait for dial
tone, then hang up.
Flash/Hook Toggles between active call and incoming call (call waiting tone). If not in conversation,
flash/hook will switch to a new channel for a new call.
# Pressing pound sign will serve as Re-Dial key.
HT503 User Manual
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