Siemens optiPoint 500 entry Operating Instructions Manual page 48

Without prior announcement:
Setting up a conference call:
First call
Consultation
In the case of a telephone with no "conference" key:
First call
Consultation
Expanding conference (to includ e up to 8 users):
Add-on conference
Storing/activating variable call forwarding:
Store
In the case of a telephone with no "store" and "call forwarding" keys:
C F::
+
Activating/deactivating fixed call forwarding:
Deactivating:
Call forwarding
Activating:
Call forwarding
Cancelling destination for fixed call forwarding:
Store
+
Disconnect/Clear
In the case of a telephone with no "store" and "call forwarding" keys:
C G;:
+ e.g.
Storing individual speed dialling numbers:
Store
+
Store
In the case of a telephone with no "store" key:
C G;A
+
Consultation
E
+
E
+
Consultation
+
Call forwarding
E
for UK or *44 +
or
+
Call forwarding
+
Store
I
for UK +
F?=
+
.
E
(not for UK) +
+
Conference
FB
+ for UK or *3.
E FB
+ +
E
+ (destination) +
I
(destination) +
G::
or for UK or #44.
F::
for UK or *44.
+
Call forwarding
.
.
E
for UK or #8 +
E
(0..9) + (destination) +
E I
+ + .
.
for UK or *3 etc.
Store
.
E
(0..9) + (destination)
I
.
.