I know this thread is old but I thought I would add a little info to it ......... the mrc AG 990 is a very old school power pack as it has no electronics .......... it is just a variable transformer and a full wave bridge this lets it deal with a higher current and not have any trouble like the control master 20 ......... I have had one running the loop in the store sence they first came out ........ and I think it will still work long after the trains don't |