The Automatic Train XChange controller allows trains to be stopped and started, two trains to operate on the same track loop, and trains to be dispatched from a multiple train yard.

A single ATX controller can operate two trains on a track loop or dispatch one of two trains alternately from a two-track yard. More than one ATX controller can be employed to incorporate multiple train control features within the same XChange layout.

A train XChange layout can be expanded with multiple routes using automatically operated track switches using the Operation of Track Switches feature.

Features are selected by installing "jumpers" across an array of seven rows by two columns of pins in the upper-left corner of the ATX circuit board.

The Train Stop and Wait feature allows a train to stop when a train enters a "stop" track block, wait for a jumpered time between zero and twenty-five seconds, then proceed. A train counter that allows a train to bypass the stop track block between three and nine times may also be configured. An additional control allows a train to be held indefinitely by operator control or by a train in another track block.

A separate control allows a train to be held in a "holding" track block while another train occupies the "stop" track block, allowing two trains to operate on a single loop of track.

The One Train Released, One Train Held/nbe feature allows two trains to operate one-at-a-time on a track loop with a passing siding, configured with two holding tracks in the separate track routes. Each holding track has a "stop" track block.

The ATX controls the "stop" track blocks. Trains are held in a "stop" track block until trains are in both "stop" blocks, then one train is released. Trains can be released alternately with an optional wait time or by a jumper selected train count.

Additional controls allow trains to be held indefinitely, enabled for release, selected by "stop" block, or to allow for one train operation by operator control or by a train in another track block.

The Both Trains Released feature allows two trains to operate on a single loop of track using two "stop" track blocks. A train arriving in one stop block is held until the other train reaches the other stop block, then both trains are released.

Support features turn a relay on when combinations of isolated outside-rail inputs are in designated off or on states. The relay may turn off when any of the designated input states changes or when a specified state occurs. Specific functions are independently selected for each relay: eight functions for relay 1 and four functions for relay 2. Detailed functions are illustrated:

"Block Control" has the ATX controlling a "stop" track blocks so a train may only leave the track block when a designated following track block is clear. The feature may be used to allow more than one train in part of a layout or to extend passing sidings to hold more than one train or to implement block control for track switches.

An automatic layout, running without close operator attention, may require parts of the layout to have different power levels to control train speed on curves, through track switches, up inclines, or down declines. Powering changes will create powering boundaries where engine center-rail pickups and lighted cars will cause a short circuit. The ATX can be used to implement "power passing" for trains traversing the layout in the same direction.

The ATX's Track Switch features allow operation of passing sidings and an automatic layout to be expanded with multiple routes. As a train approaches a track switch from the one-to-two tracks side, the switch is automatically thrown to select the train's route. The Track Switch configuration provides for non-derailing and four jumper selected operating modes: 50-50 Random, Always Same Route, Switch to Free Route/Alternating, and Multiple Alternating.

• 50-50 Random
  A train approaching the one-track side of the switch causes the switch to randomly select the route. Over a long time period, each route will be selected the same number of times.
• Always Same Route
  A train approaching the one-track side of the switch will always traverse Route-1 through the switch leg with its isolated outside-rail connected to the ATX Input-1. With two track switches at opposite ends of a two track "passing" run, trains travelling in one direction will always take one track and trains in the other direction will take the other track.
• Switch to Free Route/Alternating
  A train approaching the one-track side of the switch will take the route through the switch that does not contain a train. If both routes are free the switch will be set to select the route opposite that taken by the last train.
• Multiple Alternating
  A jumper selected (two to eight) number of trains will be routed through Route-1 for each train through Route-2.

Eight modes are available for operating any kind of track switch.

• Relays can be connected to the track switch as a relay for each route, with one relay for off/on and the other for route selection, or as a relay pair for a polarity reverse operation.
• Activation can be "Only for Change:" the track switch is activated only when the selected route is different from the last route through the switch.
• Activation timing may be "Three-Seconds," "Until Opposite Track Block Reached," "Train Over the Switch," or "Always On."

Click for more details on Automatic Track Switch Operation .