Took my Ives 258 apart for some cleaning and oiling and this thing is wired into the motor.
Steve
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Its a capacitor, but don't know why its there.
Bill
It's possible someone was trying to mitigate some RF interference or reduce sparking at the brushes.
Someone's attempt at a "keep-alive"??
Buzz
What ever it was for, it is probably really old and there is a question if it is any good. There is a way to test them, a google search found some ways. I would remove it and try the engine. Have to remove to test anyway.
Bill
ADCX Rob posted:It's possible someone was trying to mitigate some RF interference or reduce sparking at the brushes.
i tend to agree, but what a bizarre choice. 0.1uF is the value you'd want to arrest voltage spikes, but the physical size is dictated by the breakdown voltage which is ~10x the value needed.
I've heard of this being done to provide gradual starting and stopping (and to ease wear on the gear train) on coin-operated or push-button commercial layouts. When the coin drops, full power is applied to the track, but the mech accelerates gradually as the cap charges. When time runs out, power is cut and the loco coasts to a stop.
Yes prewar spur-gear drives have some built-in coasting, but adding a cap avoids the inevitable wheel spin on a full-power start and conserves the life of the mechanism. I forget the exact venue, but a friend of my father's built a display like this many years ago.
Ted Sowirka posted:I've heard of this being done to provide gradual starting and stopping ...
this would only work with DC, capacitors pass AC ... and not with a capacitor value as small as 0.1uF.
