Additional PBX services - Electronic PBXs have a number of additional services that are disabled by default.

                                                                
            Additional electronic PBX services               
                                                                
                                                                
    Electronic PBXs have a number of additional services that
disabled by default.   for additional services, apparently
need to pay extra money.  Your telephone
the station must be of an electronic type, and your device must
support tone dialing.                            
                                                                
                                                                
    > direct connection with a shutter speed of five seconds <                  
                                                                
                                                                
    If you do not dial within five seconds after picking up the phone
number, then direct communication is activated.                              
                                                                
                                                                
    > record direct number <                                                                
    *52*99 99 99#                                               
    check: *#52*99 99 99#                                    
    Cancel: #52#                                                
    where 99 99 99 is the number of the called subscriber.                  
                                                                
                                                                
    > Abbreviated dialing <                                
                                                                
                                                                
    destination: *51*11*99 99 99#                                
    check: *#51*11*99 99 99#                                 
    Cancel: #51*99#                                             
    usage: **11                                         
 where 11 is the abbreviated dialing code, and 99-99-99 is the full number   
                                                                
                                                                
    > Unconditional forwarding of incoming calls <                                                                
    entry: *21*99 99 99#                                       
    check: *#21*99 99 99#                                    
    Cancel: #21#                                                
    where 99 99 99 is the forwarding number.                         
                                                                
                                                                
    > forwarding incoming calls when busy <    
                                                                
                                                                
    entry: *22*99 99 99#                                       
    check: *#22*99 99 99#                                    
 Cancel: #22#                                                
    where 99 99 99 is the forwarding number.                         
                                                                
                                                                
    > Temporary restriction of incoming calls .e5. <          
                                                                
Restriction: *e5*password#                                
    verification: *#e5*password#                                  
    Cancel: #e5*password#                                     
                                                                
                                                                
    > Temporary restriction of outgoing communication                     
      and incoming calls <                                   
                                                                
                                                                
    Restriction: *ech*passcode#                                
 check: *#ech*passcode#                                  
    Cancel: #ech*passcode#