Another whatisit?

A vee pulley, so not intended to deliver a timed pulse. A fair number bid for it.

Odd isn't it. Some LT mags ran unsynchronized, mostly USA, but I am at a loss to imagine what this modern example might have been for.

NHH

Possibly a warm air heater/blower ignition source? or something of that ilk.

Peter

-- Peter & Rita Forbes Email: snipped-for-privacy@easynet.co.uk

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?

Julian.

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 perhaps. Peter

-- Peter A Forbes Prepair Ltd, Rushden, UK snipped-for-privacy@prepair.co.uk

I was just looking at the HT lead, it looked very much like some that I've seen, thick and with probable screening to stop radio interference?

Julian.

It's not HT, it is LT (low tension)

Peter

-- Peter A Forbes Prepair Ltd, Rushden, UK snipped-for-privacy@prepair.co.uk

Exactly, why LT? If you wanted to ignite a burner or something surely you would use a normal HT mag and sparking plug. With an LT mag you also need a mechanical ignitor of the break-point type.

NHH

OK, I hadn't spotted that. Would that make it more unlikely to have been an ignition source for a steam cleaner (say)? I suppose the output would be fed to a step-up transformer?

Julian.

Just had a thought - what about a blasting dynamo? I have the bones of an earlier model:-

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

-- Peter & Rita Forbes Email: snipped-for-privacy@easynet.co.uk

Bang goes another theory ;-)

NHH

Part of a Megger style insulation tester ?.

Gentlemen,

Do any of you have some items of interest that maybe you don't know what its for or we might not know..

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...

Julian.

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 current pulse.

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 locations.

Other applications may be found in the mining industry and in early telephone systems.

Discuss .........

Regards,

Kim Siddorn