Successful Use of Electromagnets?

[BigJim]

You are right. I left electronic "tech"ing a lot of years ago. (CMOS was still new) Memory is a little rusty. Getting back into it is a major part of the appeal of model railroading.

I must have been thinking about the protection for CMOS inputs where two diodes are connected to both power connections to prevent the input from going above the positive or below ground. Output protection diodes, like this picture from the L239 data sheet, are connected parallel to the load (coil).

 

[Gary S.]

Hey Loren, and anyone else interested:

I've got a portion of my track down now, and I'm happy to report that the double coil electromagnets are working beautifully. I've got them installed on the mainline, and i've got Kadee permanent magnets on the spurs and they are working flawlessly also. I must mention that I have not had a single problem with unwanted coupling with the permanent magnets... when I pull some cars back out of a spur and go over the magnet, so far, no problems at all.

Everything is coming together nicely.

 

[Nomad]

Hey Gary, I'm glad your having such good luck with those magnets:thumb: . It's always nice when things come together like that. Your layout is looking real good too. You might consider removing the roadbed from the siding tracks though, and taper down to the bare dirt, (so to speak). The siding tracks are usally low speed and not as well maintained as the mainline, so they are not up on high ballast, at least not in my area. I hope I explained that right.

Loren

 

[Gary S.]

I understand about the spurs. What I am doing is making all the track level, mainline and spurs at the same height, so I don't have to worry about the cars rolling around since operation is my number one goal. What I plan on doing is using sculptamold to taper the top height of the spur roadbed down to the bottom height of the mainline. I'm hoping this will create the illusion that the spurs are not up on roadbed and not as well maintained. On the other hand, since I am modeling a shortline, the mainline doesn't need to be up on a high speed main roadbed either. Anyway, as I get further along, I'll figure out what to do to create the effect, using sculptamold to raise the level of the foam up wherever needed. Ithink by using some ditches and various uneven terrain between the mainline and spurs, I can create the look you are talking about.

How are things coming on your layout?