No, buses operated by NJTransit Bus Operations do not use the trunked system. Two of the frequencies (857 & 859.3875) are set up as conventional channels. You should also program the input frequencies (812 & 814.3875). The frequencies are simplex, therefore you will not hear the mobile unit transmitting unless you have the input frequencies programmed and are in close proximity to the transmitting unit.
On the trunked system you'll hear the River Line, Academy Buses operating in South Jersey and some NJT Police communications.