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Pennsylvania Railroad

Pennsylvanie Railroad position light signals can be connected to the Signalist SC1 as in the below diagram. A second single head can be connected to terminals E,F, G and H when a single head configuration is required instead of A, B, C and D.

PRR twin head position light connected to a SC1

Pennsylvania railroad position light signal wiring diagram

PRR 'Devil Eyes' twin head position light connected to a SC1

Pennsylvania Railroad position light signal wiring

Use CV38=74 for a twin head signal using extended accessory protocol
Use CV38=67 for two single head signals using extended accessory protocol
Use CV38=8 for a twin head or two single head signals using standard accessory protocol

Note that when using the CV38=8 configuration flashing aspects can be acheived by toggling between the solid aspect and dark. Software such as JMRI will do this automatically.

PRR Rule	Description	CV38=74 Aspect N^o	CV38=67 Aspect N^o	Aspect
292	Stop	0	0	R
294	Take siding	1	-	X
291	Stop and Proceed	2	-	R Y
290	Restricting	3	-	R \
289	Permissive	4	3	\
288	Slow Approach	5	-	R /
287	Slow Clear	6	-
285A	Caution	7	-	\ Y
285	Approach	8	1	/
284	Approach Slow	9	-	/ /
283A	Medium App. (flashing)	10	-	R /
283	Medium to Clear	11	-	R \|
282	Approach Medium	12	-	/ \|
281	Clear	13	2	\|
280	Clear Block	14	-	\| Y
-	Dark	15	8

Key R=Red, G =Green, g=Flashing Green, Y=Yellow, y=Flashing Yellow, L=Lunar, W=White.
N=Normal or Closed, R=Reversed or Thrown

In JMRI use DCC Signal Mast Decoder for CV38=74 and CV38=67, use Quad Output for CV38=8

Signal reference chart for 1956 rules can be found at the Signals of the US website:- PRR PDF