# JMRI: SLSF-1973 Signaling Definition

This directory contains signaling definitions corresponding to the SLSF (Frisco) rules as described in the July 1978 Revision of the St. Louis San Francisco Railway Company publication "RULES for the Maintenance of way and Structures" effective July 1,1973, chapter titled Description of Signals. As noted in the source material, these rules are rules of the Frisco Transportation department.

Per Frisco rule 280, dwarf signals display the same indication as high signals.

Selected pages from the 1957 St. Louis San Francisco Railway Company publication "Rules of the Transportation Department" are avaialble on the Frisco Modelers and Information Group website.

See the aspect page.

Signal Mast definitions:

- Triple searchlight signal
- Triple searchlight signal with Triangle plackard
- Double searchlight signal
- Double searchlight permissive signal
- Double searchlight grade signal
- Double searchlight signal with Triangle placard
- Single searchlight signal
- Single searchlight permissive signal
- Single searchlight grade signal

Note: Signals with a triangle plackard display Approach Limited instead of Approach Medium.