The manuals for our various products describe the required commands using the US terminology that's common in the DCC world. Accessory devices can be set to CLOSED or THROWN. But not all DCC systems use the same terminology!

The documentation for Sig-naTrak® products will refer to "anode" and "cathode". When an LED is lit, the positive end is called the "anode" and the negative end is called the "cathode". To add to any confusion, by convention the cathode is often marked with a "plus" symbol.

Some users may be sent a new processor chip. This will have the correct firmware, but may have no serial number allocated. This needs to be set before the board can be used and programmed. DO THIS BEFORE DOING ANYTHING ON THE LAYOUT! A board with un-programmed serial number can be identified because its green LED flashes steadily after power up.

In general, different kinds of boards need different power supplies. This is because there are no standards for power feeds in the DCC world, and every manufacturer has (potentially) different power feed arrangements. These power feeds alL need to be isolated from each other: i.e. they need to come from separate transformer windings that are not commoned together (e.g. by a common earth). Some general rules follow.

Many DCC and LocoNet interface devices are sold as open circuit boards, to be installed into a layout by the user.

Many reported problems turn out to be electrical problems with problems being caused by inadvertent wiring errors.

One issue that has caused problems on several layouts has been incompletely crimped connectors on LocoNet cables. In several instances this has resulted in a connection that has high resistance, but isn't open circuit. The result is that the cable tests OK with an LT1 but doesn't work properly in practice.

This can be tested for by using a multimeter to look at the voltages on the cable. On a "healthy" LocoNet, the voltage measures from DCS100 "ground" terminal to the centre two LocoNet pins should be 10v or more. However if a cable has a high resistance connector, then the voltage down that segment of LocoNet can be dragged down. Voltages as low as 4v have been seen due to this. If you suspect your LocoNet is not working correctly, check the voltages to the centre two pins and investigate if is less that approx. 9-10v.

The outer pair of wires provide "rail sync" signals with the same packets as are present on the rails. These can sometimes become open circuit, often without affecting many devices they're connected to.

LocoNet carries its signal on one of the centre two wires of the LocoNet cable. However these are connected differently depending on which type of command station you gave:

You can use our products with the Uhlenbrock "Intellibox" DCC system. This has a LocoNet interface.

Many accessory boards have a "DCC accessory address". This is an address that is accessible through DCC "closed" and "thrown" commands from a throttle. Examples are all point control accessory decoders; SE8C signal controllers; and SIGM20 signal controllers. DCC addresses can be between 1 and 2048 (although many throttles can't control addresses above 999). It is important that the addresses allocated for these board do not overlap with each other.

Digital Command Control (DCC) is a model railway control system which allows controls of individual locomotives, rather than control of sections of track. This is a powerful way of controlling multiple locomotives on both simple and complex layouts. To understand its benefits, it is necessary to understand the alternative approaches.