Three-Rail Innovations uses a demonstrator to show the operation of the Universal Trackside Accessory Controller at train shows. Pictures illustrate a UTAC mounted and wired to trackside accessories. On your layout, the circuit board can be hidden by a structure or mounted underneath the track surface.

An explanation of demonstrator operation illustrates some the capabilities of the UTAC.

The demonstrator has two track sections, one high-rail (with an insulated outside rail) and one Gargraves (outside rail already insulated). Each track section is divided into four isolated rail blocks with plastic joining pins. (Each track block on the demonstrator is about 10 inches long; on your layout, track blocks can be as long as you want.) A train car in each section is moved back and forth to show the UTAC's operation of trackside accessories.

There are six trackside accessories, all operated by one Universal Trackside Accessory Controller: a Lionel 1045 Flagman, a Lionel 153 Block Signal, a Lionel 6-22947 "Mainline Die-Cast Auto Crossing Gate," a Lionel 154 Flashing Crossbuck, a Lionel 151 Semaphore, and a Marx crossing warning bell.

The car for the high-rail track section starts in the leftmost isolated track block and is moved to the right, into blocks two, three and then four.

As the car is moved right into the second track block, the 153 Block Signal changes from green to red and the 154 Crossbuck starts to flash.

When the car moves into the third track block, the 153 Block Signal stays red, the Crossbuck continues to flash, and the Crossing Gate starts to lower.

When the car is in the fourth track block, the 153 Block Signal stays red, the Crossbuck stops flashing, the Crossing Gate starts to raise, and the Marx Warning Bell sounds for ten seconds. After the bell rings for ten seconds it goes off, and will not start again until the car is moved out of the fourth block and enters it again.

When the car is returned to the first block, the Block Signal changes from red to green.

The car for the Gargraves track section starts in the rightmost isolated track block and is moved to the left, into blocks two, three and then four.

As the car is moved left into the second track block, the 151 Semaphore lowers its flag and the 154 Crossbuck starts to flash.

When the car moves into the third track block, the Semaphore flag stays down, the Crossbuck continues to flash, and the Crossing Gate starts to lower.

When the car is in the fourth track block, the Semaphore flag stays down, the Crossbuck stops flashing, the Crossing Gate starts to raise, and the Lionel 1045 Flagman waves his flag.

When the car is returned to the first block, the Semaphore flag returns to the up position.

The UTAC mounting on the demonstrator clearly shows the connections needed to operate six trackside accessories. Barrier strips are employed to make connections clear and to allow convenient changes.

• Wires to the eight isolated outside rail track sections are connected to the barrier strip on the left. (Only six are used.)
• Wires connect directly from an isolated outside rail (left barrier strip) to the center barrier strips to activate an accessory simply.
• The middle barrier strip simply provides a convenient connection from from track block combinations to the UTAC inputs.
• "Combining" diodes are used to operate more than one accessory from the same isolated outside rail track block.
• "Combining" diodes are also used to operate an accessory when train trucks are in any of two or more isolated outside rail track blocks.
• Wires from the UTAC outputs connect to each of the eight elements of the six trackside accessories on the demonstrator.

The demonstrator shows simple operation of trackside accessories as a train moves into an insulated rail block, and also shows how track blocks can be combined to operate an accessory and how the same track block can activate more than one trackside accessory.