DIYbanter - View Single Post

Wolf K

On 15/05/2011 4:16 PM, wrote:
Wolf wrote:

[snip]
he DCC decoders convert rail power (14-18V, 50/60HZ)

If you can't even the basics right about DCC, why bother posting?

[snip]

AIUI, DCC puts a digital signal on top of an AC propulsion current. The
latter is rectified to sine wave DC by the decoder, and is in turn
chopped to provide average voltages below the maximum, thus controlling
the speed of the locomotive. If this is incorrect, please elucidate.

The signal is delivered to the locomotive in the form of data packets,
whose format is specified in NMRA Standard S-9.1. This standard also
indicates that the propulsion current is AC, Vmax between 14 and 18V RMS.

My recollection of the propulsion current and the signal current
relationship is that the former is "ordinary" AC, ie, 50/60Hz, depending
on country, and the latter a high frequency, whose value I've probably
got wrong, because I wrote from memory. Kindly correct and elucidate my
errors.

Thanks,
Wolf K.