LA-141 ListenIR IR Expansion Radiator for LT-84The LA 141 ListenIR Expansion Radiator is part of the most advanced, lowest cost IR solution available. The LA 141 can be added to the LT 84 ListenIR Transmitter Radiator Combo for additional coverage of up to 30,000 ft (2787 m) with LR 4200 IR LR 5200 IR receivers or 7,500 ft (697 m) with LR 42 LR 44 receivers in single channel mode, when mounted within 100 ft. (30. 48 m) of cable length from the LT 84. Up to four (4) Expansion Radiators (LA 141) can