Re: Athearn PA to DCC

Ross Kudlick


The bottom motor brush IS NOT electrically isolated from track power!

The left side wheels transmit track power to the frame which then is
transmitted to the bottom motor brush through some contact "tangs" in the
bottom bush retainer strap. This is directly under the center of the motor
where it is difficult to see, or get to with your meter.

The TCS web site has pictures of a T1 installation in an Athearn blue box
PA1 here:

If you Google "Athearn dcc conversion" you will find several "How to"
articles and videos on installing a decoder in the Athearn blue box
locomotives. I particularly like Brian Arnold's here:

The Athearn blue box locomotives are easy conversions and highlight the
basic requirement that you need to "Isolate the motor brushes from track

I usually "swap" the top and bottom brush retainer straps; this puts the one
with the "tangs" on the top; and place apiece of electrical tape under the
motor for insurance.


Ross Kudlick

-----Original Message-----
From: [] On
Behalf Of
Sent: Sunday, September 01, 2013 4:12 AM
Subject: [WiringForDCC] Athearn PA to DCC

I am in the process of converting an older Athearn PA to DCC.
The right wheels of both trucks pick up the hot side with an angle bracket
that slides over the metal piece that goes from front to back and provides
the voltage for the single headlight as well as the motor. The left wheels
are all connected to the frame. The motor does appear to be isolated from
the frame, by both visually and electrical ohms check. I want to install a
DCC decoder, probably a TCS-1. I plan to remove the top strap, solder wires
to the two pickups and connect them both to the input voltage point for the
decoder, screw a small terminal lug to the frame and connect the other input
wire for the decoder to it. Then connect the motor, by soldering wires to
the flat contact strips, replacing the bulb with a LED and resistor. Then I
should be good to go.
Comments or thoughts?
Mike G

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