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Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
I bought this kit in a lab clearance sale, but have no idea what it is.
A metal Mullard shield is fixed to the outside of the wooden case. For stylistic reasons, I would guess that the apparatus was made somewhere between 1960 - 1965, the last gasp of the Thermionic Golden Age.
The inductance measures 9.95mH, (Peak Atlas 1%) which I take to be a nominal 10mH. Its resistance is 3R2.
The metal bars are weakly magnetized.
Screwdriver markings in the side elevation picture show that the part with the inductor wound upon it has been screwed up and unscrewed a number of times - presumably to change L.
L has the apperance of a good quality one-off workshop job.
The hook suggests that this part should hang from a retort stand and such.
The metal cylinder does not rotate.
Had it been a piece from an educational equipment company like Griffin and George, I would have assumed that it was a demonstration kit related to magnetics teaching, but Mullard appear to have made it as either a one-off or a small workshop production run.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
That sounds plausible Sulaiman, and I've always thought it had the feel of a physics demonstrator's kit to it, but have never thought of Mullard manufacturing in that sector.
I wonder at the nature of the two bobbins or spindles on the unit with the hook attached. The lower one, made of two metals, is clearly more than a structural element, and would have been expensive to make.
It has the feel of high quality machine shop work to it, so it is possible that it was designed for a Mullard in-house learning programme.
But perhaps it is something so ludicrously simple that I've overlooked it altogether, a device for estimating the distribution of magnetite particles in rhinocerous horn, for example.
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Mullard Mystery Apparatus - What is it?
