Value of old B&G kit on eBay?

Did you know that there are two sorts? The earlier ones, as on the eBay list in the OP, are straightforwardly current driven. 0 - 10mA, I think. Later ones look identical except for the work "Syncro" on the face and use sine and cosine drivers so the needle can be driven through 360o. Writing a driver for either would have its challenges, but they are so beautiful that it would be worth doing. I keep spares of everything, and when I run out I shall look for ways of driving the repeaters with modern instruments.

I didn't realise that. I thought the 360degree wind angle displays were all 3-wire. 3 phases at 120 degree, with a DC offset so each signal ranged 1 to 9 volts or something?
Or was that just the MHU?
I never did work out exactly how the wind angle sensor worked, lots of intricate coils of wire and a few transistors IIRC. But I did make it work by simply cleaning off the corrosion and bridging a pcb track that had corroded through!
 
I didn't realise that. I thought the 360degree wind angle displays were all 3-wire. 3 phases at 120 degree, with a DC offset so each signal ranged 1 to 9 volts or something?

That may be how the pre-Synchro 360o ones worked - I only have a windspeed one of those (useless to me, available for postage only). The Synchro ones are, as far as I can see, all the same whether 360o or 270o. Six wires per unit, iirc - sine, cosine and illumination.
 
That may be how the pre-Synchro 360o ones worked - I only have a windspeed one of those (useless to me, available for postage only). The Synchro ones are, as far as I can see, all the same whether 360o or 270o. Six wires per unit, iirc - sine, cosine and illumination.

Same 3 phase principles used by Stowe wind direction displays. I managed to duplicate the function using Arduino. Just some gentle trig / maths involved :-)
 
Looks like the mast cable is three-phase.
The one I sorted was a Hydra, with digital and analogue repeaters.
I assume the expensive looking Hydra box converted everything.
I am still curious exactly how the angle sensor works.
And how ours got full of salt water....
 
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