INSPECTION AND INSTALLATION OF TIMESTOPPER T-IV FINISH SENSORS (Refer to Figure 1)

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BATTERY INSTALLATION:     Slide the battery compartment cover open and install a 9-volt battery.   It is recommended (particularly for critical races like pack derbies) that you use a long life battery and that you always be equipped with a spare, fresh battery.   If the unit will be used for several hours during a Pinewood Derby competition, install a new battery at the beginning so the races won’t be interrupted with a battery change.

SENSOR INSTALLATION:     Be careful to mount the Finish Sensors in each lane along a common finish line.   First draw (or score, or paint, or tape) a straight reference line perpendicular to the lanes at the finish line.   Then drill the sensor mounting holes along this line as described in the next paragraph.   This line will be the official finish line.

At the finish line and on the centerline of each lane of your track, drill a hole 5/16" in diameter vertically through the track.   The figure (Figure 1) shows how the Finish Sensors are to be installed and how they operate, whereby each car crossing the finish line interrupts the overhead illumination from reaching the Finish Sensor located on the finish line in the middle of that car's lane.   This figure also illustrates the installation of a Finish Sensor within a 5/16" hole (see next paragraph).

The provided rubber tubes allow the Finish Sensors (the phototransistors) to be easily inserted snugly within the drilled holes.   Each tube is slit down one side (lengthwise) in order to allow a Finish Sensor (phototransistor) to be gently inserted within the tube before installation of the resulting sensor-in-tube sub-assembly into the track.   When installing Finish Sensors, be sure to position the lens of each sensor about 1/4" below the top surface of the guide rails of the track.   From the underside of the track, and using the rubber tubing provided as a protective sleeve around the body of the sensor, insert each sensor body snugly into its respectively chosen hole (per lane number associations made in step 1 above).   The body of each sensor should be positioned within its respective hole in the track such that the small transparent window is facing skyward.   By recessing each sensor about 1/4" below the top surface of the track, the portion of hole and tube left above the lens of the sensor should act somewhat as a tunnel to the sensor to partially shield it from light sources other than directly overhead.   The extra length to each tube allows you to easily grasp it from below for removal when taking down a track for storage.

Mount an incandescent lamp(s) 1 to 5 feet directly above the finish line of the track to illuminate all of the Finish Sensors.   Multiple lamps may be positioned across the finish line.   Proper operation of the sensors requires good illumination on each sensor (at times when there are no cars over the sensor holes).

ALIGNMENT MODE:     The alignment mode is used to adjust the over-head light and the photo-transistor sensors to give a positive response to the racer crossing the finish line.   The alignment mode is also useful to test that the photosensors and cables are in operating condition.   And the alignment mode is useful to identify which sensor is associated with which LED on the display, so that the sensors can be installed in the lanes corresponding to the lane numbers marked on the display.   It is advisable to mark the track lanes with their desired lane numbers.   To activate the Alignment Mode, Depress the Race Reset Switch while sliding the Power Switch to the ON (Up) position.   The front panel LEDs will have an alternating flash for about 3 or 4 seconds and then the LEDs will be either on or off.   At this point, proper alignment is indicated by all LEDs being off.   Any LEDs that are on, are not properly illuminated.   Adjust the height and positions of the light until all LEDs are off.   It may be necessary to check that all photo transistor sensors are mounted in the track such that they are pointed sufficiently upward.   After proper adjustment is done, double check the setup by blocking the light from reaching each individual photo-transistor sensor and checking that a single respective LED indicator comes on.   Turn the Power switch on the unit to OFF to exit the Alignment mode.

IMPORTANT:     To protect each Finish Sensor from potential damage caused by excessive pull on its cable, clamp each cable securely to the track within 4" to 6" of the respective sensor, leaving some slack between the fastening clamp and the sensor.   Also remember at the end of a derby, before taking your track down for transportation and/or storage, to remove the sensors and cables for their protection.

Next read the section on OPERATION OF THE TIMESTOPPER MODEL T-IV.