Help controling multiple Lionel OTC with one Lionel 2 button switch

You'll need a two pole switch with enough positions to handle all your current operating tracks and any future additions.  The Fastrack one is wired the same as the older tubular UCS tracks, here's that diagram and the lines to switch.  Notice that one of the leads has constant power and the other has track common, both unswitched.  For separate power, connect the constant power to your accessory power supply.

The two common switch poles will go to the switch, and the switch wafer individual contacts will go to each of the UCS track connections.  I'd recommend a switch that will handle at least three amps.  The good part is you won't be carrying current as you switch the rotary switch, that helps.

gunrunner has given you a good start. Think it thru.

The rotary switches can be pricey. Look them up on Mouser, they had the best prices last time I looked. Number was 690-c4d0312s-a. the help desk will put you on to a tech. they tend to be extremely helpful. There is actually one of they techs who is a model railroader. 

Remember also you will need to run one wire from the panel to each of the OTCs to do what you want to do. make sure it is the correct AWG.

Ralph

You'll actually need two wired from the switch to the OTC from the rotary switch, then you'll need a common power to all of them and of course, the common ground, which may be the track ground.  I'd probably use a TVS protection diode across each of the switched connections to the common to clamp any spikes generated by switching the coils.

Surplus places like www.allelectronics.com are a good place to look for appropriate rotary switches, as Ralph notes, from manufacturers they may be a little steep.

Thank you! Your information has been most helpful! I do have one question though; I looked up Ralph's suggested rotary switch on Mouser (690-c4d0312s-a) and it shows it is a 3 deck switch with 1 pole per deck (a total of 3 poles) and has the necessary 12 positions. Is this the one I need or do I need 2 poles per deck? The whole pole/deck thing is still a little confusing to me.

Thank you! Your information has been most helpful! I do have one question though; I looked up Ralph's suggested rotary switch on Mouser (690-c4d0312s-a) and it shows it is a 3 deck switch with 1 pole per deck (a total of 3 poles) and has the necessary 12 positions. Is this the one I need or do I need 2 poles per deck? The whole pole/deck thing is still a little confusing to me. 

I did find a 2 pole switch at Mouser with 2 decks having 1 pole per deck and the 12 positions. Would this be the one I need instead of the one Ralph suggested?

You only need to switch two poles, the other two can be supplied constantly directly to the operating tracks.

The switches Frank offers are only 4 position, so they aren't going to do the trick for you.

Here's one that has three poles (one extra for a selection light if desired) and handles 15A: http://www.ebay.com/itm/ELECTR...S-1-PC-/331018921377

Note the specifications, it'll carry 15 amps, but if you are carrying current during the switching, the ratings are only a fraction of an amp.  As long as you switch without pushing buttons on the control, it'll do the trick just fine.

One pole per deck is a simple concept if you look at a rotary switch wiper.

Take the rotary switch below you purchased.  Each "deck" is a separate layer, and in your switch would have 12 contacts around it and one common wiper to connect to them as you turn the switch.  One of those contacts around the switch will be the common that connects as you turn the switch, the other twelve will be the individual positions.  There are three decks, so there are three rows of contacts.

Glad I could assist, let us know how it works out.  OTOH, if it goes up in smoke, maybe we don't want to know!