Laminated U and I cores of low-loss magnetic material, to form a closed core of cross-section 25mm in plane of laminations, 32mm perpendicular to them, I-core length 102mm, U-core external height 102mm, internal height to take bobbin length 77mm.
Pair of pole pieces, each 65x30x25mm, length x width x height with one end shapered to part of a cone for maximum flux density. Hole drilled through total length along cone exis to take a light beam. Pole pieces will accept support rods and shading ring of accessory set 2 and may be clamped at any separation on U-core, or in contact as a non laminated I-core.
Cast aluminium alloy stand consisting of a heavy base on four rubber feet with two removable clamping arms. Maximum dimensions of base 190x200x115mm, width x depth x height. Channel, 35mm wide, 3mm deep to take transformer core, extends across full width. Integral support for arms, to rear, is below the level of the pole-pieces.
Coils for demountable transformer. Wound on rectangular insulating bobbins, overall height 71mm, maximum corss- section including extension to front panel 72x110mm, width x depth, internal corss-section 26.5x33.5, width x depth. Connection to tiop and of bobbin. Front panel clearly marked with number of turns. The 300 and 600 turns coils, intended for low voltages, each have connection to pair of 4mm sockets at 19mm spacing.
The 1200-,3600- and 12000- turn coils may be used on a mains supply and are wired to plug half of three pin flex connector. Earch pin wired to front panel and green 4mm sockets. A separate mains connector, consisting of three pin socket and 1.8m three core flex, is supplied with each mains coil.