Panasonic DBS 824 Manual page 316

FF3
Software Version CPC-S and CPC-M, Version 1 0 and higher
Address FF3 (ExtPort)# 16# (0 or l)#
Description
The offhook signaling tone can be sent repeatedly or only once
Programming
Related Programming
Issued 3/l 195
FF3 (l-16 or l-24)# 16# (0 or l)#
Extension Port
CPC-S 1-16
CPC-M 1-24
FF3 (ExtPort)# 7# (0 or l)#
FF3 (ExtPort)# 15# (0 or l)#
DBS 824-l O-400
(approximately every 6 seconds)
3-l 9