Possibly a warm air heater/blower ignition source? or something of that ilk.
Peter & Rita Forbes
Yes, very probable. A petrol fired aircraft cabin heater maybe? One other
thing - maybe it was for a ''shower of sparks'' ignition booster system for
an old piston aircraft engine starting system. I worked on some more modern
examples that used a trembler coil system, but that mag would probably do a
similar job - maybe the pulley was an extra, as standard a handle?
I don't think it would have been aircraft-related, but something like a mobile
steam cleaner driven off an engine with no mains source would fit the bill
Peter A Forbes
Prepair Ltd, Rushden, UK
Had this from the vendor:
"Inside is a single coil, there are no points, just the coil with 2 leads coming
out if it. Its the same principle as the old fashioned bicycle generator that
used to rub on the tyre to provide electricity for lighting. The set up is
therefore a single wound coil on top of 2 pole pieces, and a rotating magnet
armature. It is a simple alternating current generator. The two leads out are
not shielded, they just have very very thick insulation. We tried it on a AC
digital voltmeter and a simple spin by hand gave 4 digits on the meter, the
first of which was a 1, so over 1000 volts just with a hand spin !!, but hardly
any amps. No idea what it was for, so any guesses welcome".
Peter & Rita Forbes
Is there a precise definition of a magneto? The item in question could
possibly be better described as an alternator, albeit one with the shape
that most people would describe as a magneto. I wonder what components a
device would need, or what would such a device have to produce in order to
be considered a genuine magneto?
I've always considered a magneto to be entirely self sufficient and not rely
on external power, but after that the waters start to muddy...
How about thus.
A magneto is an electro-mechanical device for producing pulses of
electricity by spinning a coil of wire in a magnetic field applied by a
permanent magnet or by spinning a permanent magnet within a coil of wire.
The magneto may produce a low tension current from a single winding that is
discharged through a mechanically operated igniter situated inside the
cylinder of an internal combustion engine. High tension versions have both
primary & secondary windings & generate an HT current that will produce a
spark across the points of a sparking plug screwed into the combustion
chamber of an ICE. A mechanically operated contact breaker times the HT
There are various designs and broadly speaking they are either of the
flywheel type or a separate unit that may be fitted in a number of
Other applications may be found in the mining industry and in early
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