Note: The links on the left side of this page and the other Model CT-3 pages will take you to detailed information about the new coffee table's design and construction.

CTI Electronics Modules

Wirng of the CTI Electronics modules is complete. The CTI modules, along with most of the remaining electronics, are mounted on two long 1/4-inch thick plywood strips. The plywood strips are located in the equipment box under the layout. These strips (front side and back side) are shown in the photos below and in the photo at the bottom of the Lift Mechanism Construction page.

I should note that wiring and testing of the first eight blocks of track did not go quite as planned. Call it Murphy's Law (anything that can go wrong will go wrong), or call it the simple truth that two wrongs don't make a right.

When I first ran the train, I noticed that eastbound trains were triggering the westbound sensors, and westbound trains were triggering the eastbound sensors. Obviously, something was miswired. Without putting much thought into the cause (and without reading the instructions), I tried reversing the polarity of the connections to the throttle. The result was that eastbound trains still triggered the westbound sensors, and westbound trains still triggered the eastbound sensors, AND forward was now reverse, and reverse was now forward. It seems that you can't fix bad wiring by adding more bad wiring. Two wrongs definitely do not make a right.

The solution, by the way, was to change the throttle wiring back to the way it was in the first place, and then rewire the block sensors in accordance with the instruction manual. (If all else fails, read the instructions.)

Power Supplies

Power supply wiring is also complete. The next photo shows four of the layout's seven power supplies. These four, which are standard plug-in adapters, provide power for the three throttles and the layout's turnouts.

The next photo shows the 12-volt power supply that provides power for most of the layout's electronics, and the 5-volt supply that provides power for the layout's scenery lights. The only power supply that is not shown in these photos is the supply that provides power for the lift mechanism.

Four of the power supplies are protected by fuses; however, the three throttle supplies are protected by 12-volt lamps wired in series with the 12-VDC outputs of the supplies (photo below). In the event of a short circuit—e.g., a train derailment—the increased current flow will illuminate the appropriate lamp, thus limiting the current flow and protecting the throttle and its wiring. As soon as the lamp lights up, a photo diode will detect the light, and the software will then disconnect the throttle from the track. As soon as the throttle disconnects from the track, current drops to zero, and the lamp turns off.

Scenery Lights, etc.

Most of the scenery-light wiring is complete, including street lights and two of the five planned emergency vehicle flashing lights. A few items (for example, grade crossing lights & gates) will take awhile to design and construct, so they will have to be installed at a later date.

The photo below shows the first test of the lights in the main town. Although the photo doesn't show it very well, the fire engine is equipped with flashing lights, and there is a police car on the road up the hill (left side of photo) with flashing lights. More information about these vehicles (including videos) is available on the Test Track Scenery page.

While I am on the subject of lights, I should mention that all scenery lights are LEDs. Many are 5 mm high-intensity LEDs, while some are smaller surface-mount technology LEDs. Building lights are custom built plug-in LED assemblies. Each assembly includes the necessary current limiting resistors to allow it to operate on 5 VDC at approximately 15 mA current.

Photos of two types of LED assemblies are shown below. The one on the left is a 2x3 mm surface-mount LED, while the one on the right is a standard 5 mm LED. Both are mounted on resistors that are encased in epoxy. The 2x3 surface-mount LED is more expensive and not quite as bright as the standard LED. However, the 2x3 is available in white or incandescent, which means that some buildings appear to be illuminated by fluorescent lamps, while others appear to be illuminated by incandescent lamps.

For other types of scenery lighting, surface-mount micro-LEDs and nano-LEDs are used.

Fire in Fireplace

One really interesting special lighting project is already complete and operational. It is a flickering fire in a fireplace (see photo below). The fire effect is provided by three orange LEDs mounted under the floor of the house, and an electronic module mounted under the layout. The electronic module illuminates the LEDs randomly, resulting in a very realistic looking fire.

Burning Building

A burning building is presently under construction. It will use the same type of “fire effect” electronics that the fireplace uses. This will eventually be a very active fire scene involving a fire engine, fire chief's car, police car, and ambulance—all with flashing lights.

Water Wheel

Not everything is a great success when it comes to operating scenery. The water wheel (photo below) is a good example of something that didn't operate as well as anticipated. The plastic gearbox did a good job of turning the wheel; however, the gearbox noise was horrible.

Nonetheless, the concept was a success. The motor and gearbox assembly was hidden by a small removable hill, and the long shaft that drives the water wheel did not not actually touch the mill house. That was important! Otherwise, the mill house might rotate with the water wheel.

Eventually, I was able to locate a much better motor and gearbox assembly (shown below on the right). This device was very quiet and operated very smoothly. Note that the shaft on the new gearbox is made of parts that I found in my storage shed. It isn't pretty, but it works.

With the removable scenery in place, and the river at flood stage, the water wheel is beginning to look good!

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