Thanks , Greg. The board produces some “standby “ steam loco sounds - coal shoveling , some clanks , etc. I was hoping that it might have a chuff sensor ( reed switch input ) for analog sounds. One other code number on the board Is “AR1” which I found under the silicone holding the crystal osc in place. It’s definitely HO form factor but is in a G scale Delton 2-8-0 I’m rebuilding so I’m hoping to use it for analog sound.