The 20-01 four channel SELCALL translator/blanker is a replacement for the SALCOM 12-19-5000 four channel tone sequential signalling translator. The 12-19-5000 itself was a replacement for the earlier the 12-19-0000 Signalling Translator which had superseded the SIGTEC P1800/P1810 translators. The 20-01 has the additional optional of a switchable (on/off) “Tone Blanking” circuit for removing the received SELCALL audio to the operator consoles, if so desired.
The 20-01 provides a SELCALL encoder function to translate the RS232 commands from a PC based CAD (Computer Aided Dispatch) system to 600 Ohm balanced audio signals. The decoder function translates audio SELCALL sequences in the 5-Tone + Status or 13-tone SELCALL formats from radio equipment to RS232 data suitable for CAD software.
The encoder/decoder functionality is configurable using the command set currently supported by the SALCOM 12-19-0000 and the primary command set in the SIGTEC P1800/P1810.
Each 20-01 PMR channel (“processing channel”) provides two RS232 serial ports – Each with independently configurable SELCALL mode and port data rate. This allows one port to be configured to signal Fire Stations using the 5 Tone plus Status format, with the second configured with the FENZ 13-tone format for decoding signalling from Fire appliances and cars.
Each radio channel slot utilises a 6-wire audio interface for connection to the radio equipment and an interface for an operator console which provides the “Tone Blanking” feature on all inbound audio traffic.
Audio levels for the console port, radio port and SELCALL output to the radio port are independently adjustable for each channel.