Siemens TC12 Installation, Commissioning And Maintenance Handbook page 153

4.3.3.3 Carrier Detect Level Switch
This switch selects the carrier detect sensitivity when:
The test set is in Instation mode and is receiving Reply messages from OTUs.
The test set is in Outstation Mode and is receiving Control messages from the
Instation.
The test set is in Monitor mode and is receiving both Control and Reply
Turn the Carrier Detect Level Switch to the desired sensitivity, -33 dBm, -39 dBm
or -42 dBm (these levels are equal to the carrier detect levels that can be set on
the Modem PCB and OTU PCB). –39 dBm is the standard selection for use in the
U.K.
4.3.3.4 Transmit Level Attenuation Switches
IMPORTANT NOTE - For UK Usage the Transmit Level of the Test Set should
only be set between –13 dBm and –63 dBm. Under NO circumstances should
the transmit level be set higher than –13 dBm, i.e. the attenuation switches
should be set to at least 13 dBm (see below).
The test set front panel contains six transmit level attenuation switches. These
switches select the transmit level when:
The test set is in Instation mode and is sending Control messages to OTUs.
The test set is in Outstation Mode and is sending Reply messages to the Instation.
The Maximum transmit Level is 0 dBm when all attenuation switches are in the
OFF position. Setting the appropriate attenuation switch to ON, allows this 0 dBm
level to be reduced by 1, 2, 4, 8, 16, 32dBm or any level between 0 dBm and –63
dBm by setting combinations of the attenuation switches to the ON position.
4.3.3.5 Test set/Handset Selection Switch
This switch allows the switching of the PC serial port 1 between the test set
modem 1 (when it is being used in test set mode, where it is used for Control
messages) and the 25 way D type "HANDSET" when the PC is to be used to
communicate with other hardware via its serial port comm1, e.g. controller handset
port when PC is acting as a handset.
When being used as a test set this should be in test set position.
IF the test set is to be used as a handset for an STC controller etc, using the
STC PITS software also supplied with the test set. The switch should be set to
handset and the appropriate cable connected from the test set HANDSET
socket to the controller etc.
OR
IF it is to be used as a monitor for a TC12 Instation PC, using the STC CTERM
software also supplied with the test set. The switch should be set to handset
666/HE/43100/000
TC12 Installation, Commissioning & Maintenance Handbook
Page 143 Issue 10