Would a tec three transformer (throdle controler) work for Lionel, and Marx trains? What would be the best way to wire it up? Thank you all.
The MRC Tech 3 (not Tec 3) is good for 0-20 volts DC, 30 volt-amperes, and 2.3 amperes. That’s enough voltage but a little light on power and current for many O-gauge trains. You will get continuous whistle or bell unless you disconnect them. Manufacturers of modern locomotives may claim (probably wrongly) that running on DC will damage their products and consider that you have voided any warranty. Traditional locomotives will not mind the DC, but will tend to draw more current than newer ones. Both old and new locomotives are easy to modify for DC reversing if you want to do that.
What Bob says is true, but it does depend on the kinds of trains you are going to run.
First off, many smaller Lionel and K-Line transformers are light on amperage too. They will run your locomotive and a lighted caboose, but not much more. Illuminated cars place excessive strain on these smaller transformers. Also, are the locomotives the lesser expensive modern type with truck mounted DC can motors or the older type (or more expensive newer ones) with the open frame AC “Pullmor” motor? The truck mounted DC can motored type use far less current than does a loco with a “Pullmor” motor.
For a period, many of the lesser expensive locomotives made during the MPC years and into the LTI years did not come with diesel horns, so they are easily run on DC current. And once you hear the horn on some of these locos you may want to disconnect it anyways.
I opted several years ago after some experimenting to run my layout on DC current. Most of my locos are the lesser expensive truck mounted DC can motored type. I have discovered that by removing the circuit board reverse unit and wiring the motors directly to the feeder wires, that these types of locos do run better on DC current. They also use less current too. I like the MRC power packs, but for economic reasons opted to make my own reverse button unit with a full-wave bridge rectifier (similar I suppose to the Lionel 6-5900, no longer made) and use my trusty reliable 1033. With the B-U voltage setting (0-11 volts) I get smooth operation, can make the locos crawl, and can add plenty of illuminated cars while never worrying about a young visitor running the train too fast and off the track. Of course, with the lower voltage efficiency of the locomotive, I have to use lower voltage bulbs in all cars and locos for adequate illumination. Instead of the typical 12-18 volt bulbs I use 5-7 volt bulbs. I also prefer off board sound and for the investment, you simply cannot beat the value of the MRC #312 Sound Station. I think had Lionel come up with tha