Author Topic: Douglas Dragonfly Ammeter and Bulb Mounting Bracket Wanted  (Read 116 times)

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Offline BrmBrm

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Douglas Dragonfly Ammeter and Bulb Mounting Bracket Wanted
Including the resistor winding (if that's what it is).
 :idea: Or details of how to make the bulb mounting bracket and resistor.  :idea:

Offline eddie

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Re: Douglas Dragonfly Ammeter and Bulb Mounting Bracket Wanted
« Reply #1 on: 30 Nov 2018 at 17:05 »
The baseplate is just 1/16" thick tufnol with the bulbholder and resistor mounted on it. The ignition warning light bulb is a 2.5 volt bulb with the resistor wired in parallel to it - thus dropping the bulb voltage to 2.5 volts, but more importantly, permitting the ignition system to keep working in the event of a bulb failure.

  Eddie.

Offline BrmBrm

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Re: Douglas Dragonfly Ammeter and Bulb Mounting Bracket Wanted
« Reply #2 on: 01 Dec 2018 at 17:00 »
Thanks Eddie, I'll get a 2" ammeter and have a go at the bulb mounting bracket and resistor.
any idea of the resistance value. Possibly a piece of wire from an old electric fire element,
Thanks again.

 

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