Williams F7 with true blast horn

[Iowa Meatpacker]

I just picked up,these units to repaint in the Chicago  Great Western livery. They came with out any paperwork, and I am trying to figure out the horn/bell sequencing. Anyone have the key to the horn and bell sounding sequence?

Thanks.

[ADCX Rob]

It's too simple to believe - whistle/horn button starts the horn sequence, it ends on its own.  Bell button starts the bell, bell button again stops the bell.

[phillyreading]

If it is True Blast 2 it will play the grade crossing sequence for the horn or whistle button, and the bell button will activate the bell like ADCX Rob mentions. True Blast 1 only has the single horn sound and bell. If the engine has diesel revving sounds and/or train leaving announcement on start up you have Station Sounds from the Crown Edition era, which I like better then the True Blast 2 horn unit.