I have a small starter layout (N scale on a 4x4 layout) and wanted to try DCC, so I purchased a MRC Prodigy set based on the recommendation at my local hobby shop. Since I'm still in the layout phases, I've yet to purchase a locomotive with a decoder yet. I was testing the layout with a Kato Budd RDC car just to make sure power was functioning. When I throttle down to a setting below "10" (throttle goes from 0 -90), the loco stops and makes a squaling noise. Once I throttle up over 10, the car moves and the squeal stops. Any ideas what causes this? I cannot slow the loco to a realistic speed for coupling if I can't go below 10.
Prodigy DCC - low speed = locomotive squeal
Jun 09, 2004
1 Replies
DCC presents a fairly high frequency square wave AC of about 13.2 volts to the tracks. It modulates the relative duration of the positive and negative swings to signal decoders. To operate DC locomotives, it "stretches" either the + or the - side of the signal (forwards or backwards) to give a net voltage so that the motor vibrates more one way than the other.
When the motor is stopped (equal + and -), it is really vibrating and the squeal you hear is that vibration. For most motors, no harm is done; there are some sealed motors which will overheat, but I don't think your RDC is one of them. I wouldn't leave an engine in that state for long just to be on the safe side, but the squeal is normal.
Ed
in article fILxc.39302$ snipped-for-privacy@twister.rdc-kc.rr.com, TMN at snipped-for-privacy@hotmail.com wrote on 6/9/04 2:57 PM:
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required