What's the difference between Atlas GP35's (Japan and China versions)

[randgust]

OK, the original Atlas/Kato weighs in a 92.2 grams.

An "Atlas Classic" weighs in at 77 grams

New production (full DCC board) weighs in at around 65 grams.

What's really impressive is that the traction coefficient of my Kato-built GP35 runs around 20%, an Atlas Classic pulls around 14% out of the box and will go up to 20% once the plating wears off the wheels.   Slick-wheel new production Atlas is around 10%.   So you can see there are measurable reasons why I really like the old girls if I'm trying to actually pull a train.

And if you think this is a spread, the all-time worst is a 1982 Kato GP38 vs. a 2000 Atlas GP38, in terms of weight and tractive effort.

[peteski]

Word of warning if planning on replacing the Yellow LEDs with White LEDs:
White LEDs have very low tolerance for reverse current (related to reverse voltage).  That means the LED can get damaged (burned out) easily when running on DC with no protection diode.  Also, white LEDs are very efficiant and the BEMF from the motor in DC locos will make the LED opposite the travel direction flicker when the wheels lose contact with track (running over dirt in the rails).  To prevent that flicker, a capacitor needs to be added in parallel with the White LED.  If interested, I can whip out a diagram of what is needed for a white LED conversion.