Tommy
Hello & Welcome to the Forum!

I haven't been able to locate a schematic for your "818-5000-040 Circuit Board RailSounds" but the Lionel Parts & Service Department may have one available.
If not, your Elec. Engr. friend should be able to reverse engineer your board and you can go from there.

Happy Rails!
Dave

Thanks, Dave!   I'll contact Lionel Service/Parts.

Tom

Greetings and Merry Christmas,

My name is Tom Cox and I live in Chapel Hill, NC.  I only have TWO Lionel items, but I love them.  They are large scale, 1:32.  They are a powered Burlington Northern GP-20 with Rail Sounds installed, and an  un-powered unit to go with it.  I bought these at a train show circa 1998-2000.  I'd love to talk with others who run Lionel Large Scale.  I see there is a Large Scale Forum here, but there's only one post.

Here is a nice story that shows the realism of Railsounds.  About 15 years ago, I had a big oval of track set up on our front patio, for my GP-20.  One morning my wife and mother in law went for a walk around the neighborhood. While they were gone, I came out and started running my GP-20, blowing the diesel horn and activating the bell.  Several hundred yards away, completely out of sight,  my mother in law turned to my wife and said,  "I didn't know there was a railroad track in this neighborhood."  That's how loud and realistic the sounds are.

I'd like to learn more about the possibility of adding Command Control.  But this GP-20 is DC powered.
I've read the manual carefully but still have some questions.  If anyone knows of a good resource, I'd appreciate it.

Regards and Happy Holidays,

Tom