The interesting fact about that building is that it used to house the CTC boards and dispatchers for the entire WP, from Oakland to Salt Lake City. All WP traffic went through downtown Sacto, but to be a good neighbor, WP had a policy (I was never certain whether it was official, and written, or was fairly informal) of not running trains through there during weekday rush hours. Crews knew it as the "iron curtain," in my recollection.
When traversing downtown Sacramento at all other times only the bell was rung continuously. No horn unless something or someone on the track was creating additional danger. Speed limit, per Special Instructions, was 15 mph.