This is the most popular slow-motion turnout machine. With linkage included, it's very easy to install, includes an auxiliary set of DPDT (Double-Pole Double-Throw) contacts, is usable with all scales and is made in the U.S.A. Here's how it works...

Mounting is easy: Drill a hole in the roadbed to allow a control wire to go down from the control hole in the throw-bar of the turnout. Screw the Tortoise to the bottom of the layout so the control wire will be in-line with the hole. Poke the wire through the hole and attach it to the Tortoise. While the linkage that comes with the Tortoise is adequate for most turnouts, many people substitute a piece of piano wire of the same diameter (piano wire is a bit stiffer) or the next size larger when using Peco turnouts with the over-center spring. We carry two sizes of piano wire, but recommend the 0.039.

The Tortoise motor is wound with very fine wire. As such, there is a lot of resistance in the windings. This means that it draws very little current and makes very little heat. This affords several advantages: cut-off contacts are unnecessary, no burned out coils or other components, and since the motor is always powered, it always holds pressure on the points to the stock rail, and direction-indication LEDs can be wired directly in line.

Controlling the Tortoise is easy. Applying DC voltage in one polarity makes it go one way. Reversing the polarity makes it go the other way. Many people simply use a DPDT toggle switch to control the polarity. There are ways to use SPDT switches with two DC power supplies or an AC power supply. Since the Tortoise draws so little current, it can be connected directly to a Digitrax DS44, DS54, DS64, or many other turnout controllers (in lieu of the toggle switch). If manual control is desired along with DCC control, use the DS54 or DS64 and connect push buttons to their inputs. This allows control via local push buttons, your hand-held throttle, computer, or route programming in Chief, TD-SRC8 or computer.

The Tortoise has a set of DPDT contacts that can be used for various things such as powering a turnout frog, controlling a signal, or even controlling the track polarity in a reverse loop or turn-around wye. They can even be used to wire the tortoise to have three stopping points: thrown, centered, and closed.

While these contacts are supposed to be "break before make", some are not. What this means is that one set of contacts are supposed to break continuity before the other set makes continuity. If a Tortoise makes before breaking, it will cause a short if used to power a frog and in some other applications. If this is the case, you have two or three alternatives...

Obviously, the first alternative is to send the Tortoise to Circuitron for repair or replacement. If you're not worried about voiding their warranty, you can open the Tortoise and correct the problem. Correcting the problem is very easy. The contacts are wipers that run along some metal traces. You can either cut the offending traces a little shorter, or squeeze the offending contacts a little smaller. Another way is to use a single contact to control an external DPDT relay.

The last alternative that some people use, but we recommend against, is installing an 1157 automotive bulb in one of the leads. This keeps it from creating a full short, but also will keep any Short-Circuit Protection from working. This means that if you really do have a short on the track at that point, the Short-Circuit Protection won't work and there could be up to 3 amps coursing through the truck of your loco. 3 amps is enough to melt truck parts on HO- and S-scale cars or locomotives, but can melt the trucks right out from under an N-scale diesel.