I have a Lionel 85003 large scale GP20.  I'm really fond of it!  My question concerns Railsounds, specifically the diesel motor sound.  That motor sound is too loud in relation to the horn and bell.  But there's no way to change JUST the diesel sound.  If I turn down the volume with the knob on one of the trucks, it turns down ALL sounds.
An electronic engineer friend of mine suggested contacting Lionel for a schematic of the card, so I could put a resistor in place, just for the diesel sounds.  But I know Lionel guards that technology very, very carefully! So, I thought I'd ask for ideas on this forum.  Thanks!
Tom

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