How to – T1 Circuits and Wiring – Das Blinken Lichten Jan 21, 201030 thoughts on “ How to – T1 Circuits and Wiring ” Raul May 14, 2010 at 8:16 am. Question? Most documents I have read for how to wire a RJ48C or RJ48x say connect R1 & T1 to pins 4 & 5 and connect R & T to pins 1 & 2. This means the pinout on my RJ48 jack is not the same as the jack in the demarc box. Which is correct?