![Black Box FX1236OA Manual Download Page 18](http://html.mh-extra.com/html/black-box/fx1236oa/fx1236oa_manual_2764154018.webp)
17
CHAPTER 4: Operation
4. Operation
4.1 Incoming Calls
The Outgoing only units (FX6412OA, FX6824OA, FX1236OA, and FX1648OA)
do not support incoming call applications. The units were designed for outbound
calling only.
4.2 Outgoing Calls
Any IST device connected to a port on the Plug and Play Phone Line Manager
XLO can access dial tone to make an outbound call. The number of IST devices
that can be in use simultaneously is equal to the number of telephone lines
connected to the Plug and Play Phone Line Manager XLO. See the chart in
Section 3.1
for primary IST to Line Port connections.
Outgoing calls will cause the IST Port LED and the Line Port LED to light solid.
If none of the line ports are available (busy on another call with another IST port),
then the originating outgoing IST Port LED will flash until an outgoing line port
does become available. If any of the line ports have line present switch (SW1
and/or SW2) set to on, and there is no line attached, the Line Port LED will flash
and then pass the call to the next line port. When an available line port is accessed,
both the IST Port and the Line Port LEDs will light solid and remain on
throughout the duration of the call.
When an IST device hangs up (goes on-hook) and terminates the outgoing call,
the IST Port LED will go out first and the Line Port LED will flash for 3 seconds (to
allow the line to stabilize) before another IST Port can access the line for dial tone
and outgoing calls.
4.3 Data-Transmission Speed
The Plug and Play Phone Line Manager XLO is transparent to speed. It has been
designed to transmit data at the highest level of speed allowable on a business
telephone line.