Gotta have that whistle! (That's 99% of the reason a 5 year old wants to run a train set. :-) )
OK! You guys have convinced me. I have gotten way too complicated, just by trying to go too cheap with my little AC transformer.
I'm gonna spring for either an LW or SW transformer to run the trains on AC, and use the little transformer (plus a bridge rectifier) just to run DC accessories.
I managed to buy a Scout engine and tender, in VG condition, all working, for only $45.00, so that is why I am going to run AC in the tracks. The LW and SW transformers have whistle and reverse buttons, so that eliminates many of the problems in wiring a separate whistle. (If it doesn't, I will power a free standing whistle with DC from the bridged transformer.)
I am starting a new post about the LW vs. SW choice. If anyone has any pros or cons on these, I would greatly appreciate your replying to the new post.
None of the great info you provided so far on reverse polarity switches, whistle control boxes, and bridges will go to waste, as I will run an separate inner loop, with yard runners, on DC. (These won't be working a layout yard, but will just be cute little engines hauling a couple of cars around, between the main AC tracks.)
Thanks for all of your advice so far.
Mannyrock
