time signatures are scalable, but generally for people working with step sequencers, yes, each of the 16 steps is a 16th note, and altogether they make a bar.

a typical hard trance kick/bass sequence would have the kick firing on 1, 5, 9, 13, and the bass on 3, 7, 11, 15.

psytrance would have the bass hitting on all 16, but with the hits that coincide with the kick drum either eqed or compressed to stay out of its way. in addition to eqing, you need a synth with really fast envelopes for this to work, else it turns into a big muddy mess with the notes piling up on each other. for this reason many people actually construct their basslines out of drum samples (kicks or lo toms) instead of using a synth.

with techno, it's anything goes, but if you start with the hard trance style bassline, you can gradually add to it and make it more and more complex as your eqing skills grow.