Full track voltage 18V I'd have thought. I've not seen any voltage dropping electronics in mine.
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Oh hang on - I'm thinking of my heavyweight coaches. George Schreyer reckons the bulbs in those (larger bulbs than the Sierra) are only 14v.
Are your Sierra coach lights track powered or 9V battery? My pair of Sierras are from a start set, being the simpler version with no interiors nor lights. The underframe has mouldings for lights and smoke switches but no sign of a battery compartment?
Replacement bulbs for Sierra coaches and caboose marker lights are part 29502, sold in packs of 10.
Still not seen any mention of voltage yet.
Bachmann uk website says they have 29502 in stock at £14
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