23-04-2022, 08:48 PM
Hi Jeremy
The standard setup for a Ruby is a 6 volt "Third Brush" generator. This does its own regulation (after a fashion) so it doesn't actually need a Regulator in the full sense of the word, just a Cut-Out plus a half charge resistor controlled by the Lighting/Charging switch.
One possibility is to use a modern power diode in place of the Cut-Out, a Schottky type is best as it only drops about half a volt. A current rating of say 20 Amps or more would suit. It might benefit from a small heatsink as it will dissipate a few watts. All the cutout or diode does is to stop current flowing back from battery to dynamo when revs are low or the engine is stopped.
The half charge resistor can be replicated with a modern power resistor, it needs to be about 1.5 ohms and rated at about 5 watts.
Build both these components into an old empty cutout or regulator box and you will keep a period look.
The standard setup for a Ruby is a 6 volt "Third Brush" generator. This does its own regulation (after a fashion) so it doesn't actually need a Regulator in the full sense of the word, just a Cut-Out plus a half charge resistor controlled by the Lighting/Charging switch.
One possibility is to use a modern power diode in place of the Cut-Out, a Schottky type is best as it only drops about half a volt. A current rating of say 20 Amps or more would suit. It might benefit from a small heatsink as it will dissipate a few watts. All the cutout or diode does is to stop current flowing back from battery to dynamo when revs are low or the engine is stopped.
The half charge resistor can be replicated with a modern power resistor, it needs to be about 1.5 ohms and rated at about 5 watts.
Build both these components into an old empty cutout or regulator box and you will keep a period look.