DCC Impulses Column - 2
2
2: Opposite rail track pickup added to an O-scale
locomotive.
Variations in track height can pick wheels off the track and dis-
rupt power, as can out-of-gauge wheels or track.
The problem is enhanced if your loco doesn’t have all-wheel
power pickup. Sometimes the wire to a truck breaks, leaving
those wheels not connected to the decoder. Some locomo-
tives are designed with only a few wheels picking up power: for
example, brass steamers, where the loco usually picks up from
the right rail and the tender from the left.
What about opposite rail pickup?
Personally, I recommend adding pickups to locos that are not
designed for all-wheel pickup. Nothing beats having all the
wheels bringing power to you. However, even then disrup-
tions will happen.
Figure 2 shows what I did with an O-scale brass steamer to pick
power off the drivers. The axles pick up off the right rail and
keep the frame at the right-rail voltage. I installed a printed
circuit board that was insulated from the frame of the loco and
added phosphor bronze pickup wires to rub on the tires of the
drivers. The tires were in contact with the rail, but were insu-
lated from the rest of the wheel.
MRH-Mar 2013
