early HO ac gilbert hudsons run on ac power.

[retsignalmtr]

i recently bought an A C Gilbert HO scale hudson locomotive that runs on AC power. does anyone know about how old it would be and can it be converted to run on DC power?

[daveklepper]

I had such a Hudson when I was a youngster. It will run on dc power without modification. However, if the sequential reverser is working, like its operation on ac, it will go forward and then the next time you apply power it will reverse and then go forward, etc. Reversing the polarity with the motor that comes with it will not change direction because both the field coil and the armature are reversed, cancelling out the effect of the reversal.

Pittman, the permanent magnet manufacteror located in Sellersville, PA, right on the LVT Liberty Bell Limited Interurban Line, made a permanent magnet specificlly for this locomotive, with most of the magnet material in an extension cylinder that fitted into the model's boiler. Replacement of the wound field coil with this permanent magnet made the locomtive behave like a normal HO model with polarity reversal and also improved smoothness of operation and ability to haul. In the fall of 1948 I went to Sellversville, using the PRR to Philly and Market St. El and the interuruban to visit Pittman. I like the conversion.

[daveklepper]

I should add the sequential reverser was in the tender, and it alternated the connections between the field coil and the armerture to reverse with every application of power.

[daveklepper]

I should also note that the sequence reverser (which switches polarity of the amerture with respect to the field coil) is NOT needed when the Pittman permanent magnet is installed (would mess things up), and the model locomtive will not run on AC with the permanent magnet. Also getting the polarity right to conform with other HO models might take trial and error.