Hi Doug
here http://www.pinwiki.com/wiki/index.php?title=EM_Repair then http://www.pinwiki.com/wiki/index.php?title=EM_Repair#Bally_Score_Motor and nice http://www.pinwiki.com/wiki/index.php?title=File:BallyScoreMotor3-4View.jpg (from left to right the Cams "SCM-1", 2,3,4,5 ...). Here http://www.pinwiki.com/wiki/index.php?title=File:Bally_Motor_Switch_Levels.JPG on a given cam: The levels - we see (cam 1) SCM-1A, SCM-1B, SCM-1C, SCM-1D.
Here http://www.pinwiki.com/wiki/index.php?title=File:Bally_score_motor_timing_1975.jpg there is the "timing chart" - the cams are shown top-down --- from left to the right is shown a FULL revolution. The definiton of on Bally and Williams "a TURN" is "HALF a revolution, turn of 180 degrees". Position "0" is "at home, Motor is not running" - then positions "1", "2", "3", "4", "5", "6", "7" comes one after the other as the Motor makes a turn (((of 180 degrees))) - and the end of a turn is: Reaches again "position 0" and stops.
Unfortunately the "timing chart in pinwiki" does NOT match the "picture of the Bally Score-Motor in pinwiki" --- they write: Picture shows the motor of Night Rider - we must look at ipdb-schematics: http://mirror2.ipdb.org/files/1677/Bally_Night_Rider_Schematic.pdf - at ipdb-schematics-A/B-1/2 is the corresponding timing chart - TWELVE cams are shown.
Something rather seldom: Look in the schematics at "cam 12" --- see "actuated on left-0,1,2,3,4,5" then NOT actuated on "left-6,7,right-0,1,2,3,4,5" then "actuated on left-6,7".
Therefore on Nightrider the "cam 12" is NOT (180 degrees) symmetrical. ALL other cams are (180 degrees) symmetrical. The reason / purpose of the cam-12: It has the function of (other solution would be) "Alternating-Relay, Change-Relay".
Lets look in the ipdb-schematics of Capt. Fantastic at Schematics-A/B-35/36/37. ELEVEN cams - everything is (180 degrees) symmetrical. The "cam 2" does pulse all it switches (SCM-2A, SCM-2B, SCM-2C, SCM-2D, (maybe -E, maybe -F (?)) - "cam 2" pulses FIVE times per turn. "Cam 7" actuates its switchstack ONCE in a turn --- rather to the end of a turn - at positon-5.
Lets look again at post-31, JPG --- the "green-1,2" I call "Initial-Current, Initial-Circuitry" so the "green-3" starts pulling --- as it pulls: The switches are moved and the closing "green-4" enables "Self-Hold-Current, Self-Hold-Circuitry". AS SOON as "green-4" closes / is closed: "green-1,2" can open.
Let us let roll the ball through the open gate --- You will be rewarded with some points - the "Bottom Lane Gate 300 Relay" is made pulling (it establishes its own Self-Hold-Circuitry) - the "green-5" does open - NOW the "green-3" STILL pulls (Self-Hold-Circuitry through "green-4,7"). But the "Bottom Lane Gate 300 Relay" makes /made the Score-Motor do a turn --- so time comes when the Motor actuates "cam 7" - SCM-7B opens and the Gate-Relay (green-3) looses Self-Hold-Current and quits pulling so "green-4" opens.
Bally made this (SCM-7) to have a "delay / time elapses" - Ball rolls through the open gate --- after a short period of time the gaten then closes.
This "delay / time elapses" may not be needed when the pin simply changes to the next ball / next player (pulling Outhole-Relay - the Outhole-Relay also makes the Motor do a turn) --- but it is there - we must accept this as a fact. Greetings Rolf
P.S.: Do You have faults in the pin ? - Write.