Ace Olympic V Xmit and "ProStar" Rcvr.
If it has a gold sticker it is legal to use.I'm not sure when ACE quit making the "Olympic" system, But it's safe to assume that if has been gold stickered it's older than 1991(unless the user wanted the sticker,just to be able to show it had one). Incidentally, the transmitter circuit is the same(uses the same IC "NE5044") as the Hitec Focus 4 & 6, or the Futaba Atack & tower systems produced until a few years ago,So it's hardly outdated and "obsolete".You can tell if it's mode 1 or 2 by which stick does Not center itself( throttle).If it is the wrong mode just move the "centering" spring from one stick to the other.Adjacent channel rejection is all done by the receiver, the ProStar is a good receiver and clearly OK to use. You could always send it to a shop for a "Tune-up",But whether it's needed is a matter for debate.It never hurts to have a system tuned,but how often it's Needed is a matter of opinion.