Another Analog Problem I Need Help With!

I'm trying to get Miniatronics Point to Point Automatic Reversing Unit to work. The analog engine does run back and forth, but only if I keep manually
changing directions. (It's supposed to automatically cause the engine to reverse directions when it goes over a light sensor installed between the ties at each end of the point to point section of track.) I'm using a Bachmann Spectrum power pack. It's as if the light sensing unit isn't even connected! Also, the instructions say that you can adjust the sensitivity by turning the knob for each sensor until the LED lights up - well, I tried adjusting both, and could not get either LED to light up, at full, one way or the other. Is it possible the included 12v transformer isn't producing enough juice to power the unit? I ask because I tried crossing the output wires, and barely could get a spark out of the thing!
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Frank Eva
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Ouch! Don't do that! Get a multimeter. Next make sure that you have plenty of light over those sensors. You can use your multimeter to make sure that the sensors are working correctly. The sensor should measure about 6,000 ohms in bright light, 600,000 in deep shadow.
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Just my $0.02 worth. Hope it helps
Gordon Reeder
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To adjust a light sensoe you need to shade the sensor being adgusted. Shade the righr sensor and adjust its knob untel the LED lights. Uncover and the LED should go out. Do the same for the left sensor. The unit should work then.
Frank Eva wrote:

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Frank Eva wrote:

If you have this set up as a diorama and want to use it in a dark room you could put a scale street lamp almost directly over the sesor. That way when the room is dark the lamp over the loading platform will do dual service.
If the stop point is in a tunnel a small lamp almost directly over the sensor will be needed.
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