Can you run an un-modified locomotive together with a locomotive equipped with a digital decoder from a digital command station at the same time?
The standard allows for this, although some care needs to be exercised in its use. We refer to this type of operation as analog compatibility mode. The signal is symmetric around the 0 volt level which provides a 0 volt DC component. By expanding the length of the zero bits on the positive side of the signal a positive DC component can be added. Likewise by lengthening the bits on the negative side of the signal a negative DC component can be added. Only the 0 bits can be lengthened in this manner. The result is a non-zero average DC voltage which will run an unmodified locomotive. However, since the complete signal gets to the motor, the stretched zero side causes the motor to turn, and the following instant the unstretched side (the opposite polarity) tries to reverse the motor. The longer (stretched) side wins, but motors do run more noisily and generate more heat. Some high precision can motors (the ironless core type) may be permanently damaged.
Related Questions
- Can you run an un-modified locomotive together with a locomotive equipped with a digital decoder from a digital command station at the same time?
- How is a locomotive that does not have a command control digital decoder installed affected by exposure to the command control signal?
- Can you run a digital decoder equipped locomotive with a conventional 12 volt DC power pack?
