The telecommunication input channel controls the connection to a telephone balance unit (or hybrid). It features a balanced mono line-level input on Neutrik XLR and a balanced line-level cleanfeed output for return to the hybrid. Selecting the CUE/PFL & T/B button routes the pre-fader input signal to the monitoring system where the signal can be heard via headphones and/or loudspeakers. Additionally, talkback is automatically routed to the caller via the cleanfeed system. This allows the presenter or technical operator to communicate with the caller before putting them live on air. The PFL can be automatically deactivated when opening the fader.nnThere is a remote logic output to put the hybrid "on hold" using the LINE HOLD button. The remote output on the 9-pin D-type socket is driven by an NPN opto-isolator and can be momentary or latching.nnSelecting the PGM and/or AUD buttons routes the channel's audio output to the PGM and/or AUD mix buses. The buttons are illuminated green to indicate routing status. Changing the PGM button state is inhibited when the channel is "live".nnSelecting the PGM button also routes the channel to one of two true cleanfeed buses (jumper selectable). When selecting the AUD button only, for example to record off-air telephone conversations, a cleanfeed is generated via the channel's mix-minus system. When both PGM and AUD are selected, the channel operates in true cleanfeed mode, sending the PGM signal to the cleanfeed bus.nnEqualisation is fitted as standard and is activated by the EQ button, offering 10dB of cut and boost at HF (6.5kHz) and LF (100Hz). The EQ button switches the equalisation in and out of the signal path and illuminates yellow when EQ is active.