With primary of heavy gauge enamelled copper wire, approximate resistance 0.5 ohms wound on former 110 x 30 mm length x diameter. Secondary coil of fine enamelled copper wire, approximately resistance 100 ohms on former 110 x 82 mm length x diameter. Both coils fitted with 4 mm sockets. Iron core 120 x 15 mm length x diameter.

Transmission Type 30 x 25 mm. available 15000 lines per inch. Plate covered with mounted in plastic frame.
Diffraction Grating School quality 25 x 30 mm. 13400 lines per inch mounted in plastic frame.
Transmission type 38 x 50 mm. available 15,000 lines per inch. Replica on glass plate covered with another glass plate.

Pocket size multimeter is self-contained portable test set that measures a wide range of Voltages, Currents and Resistances. This is an indispensable instrument for servicing and maintenance of electronic equipment, radio and television. The meter is so designed and its movement is heavily damped to avoid damage to the meter movement.

DC Voltage : 200mV-1000V+ 0.5%+2

AC Voltage : 200mV-750V+ 1.2%+10

DC Current : 200ohmA-10A + 1%+2

Resistance : 200Ohm-2000KOhm + 0.8% + 2

Maximum Display : 1999

Display Size : 16 x 48 mm

Range : Manual

Standard Accessories : Battery, Testing Probes with Instruction Manual

To explain the principle of dicode

An accurately balanced magnetic needle, strongly magnetised is fitted with hardened steel pivot marking in jewels cup bearings. The needle can be easily removed for reversal. The inclination scale is of chrome brass graduated in degrees 0-90 four times. The case is made of non-magnetic steel alloy, duco painted, has easily removable plate glass window and rotates fully on a heavy brass base, is rotation being measured by a brass chrome dial reading 0-360^o. It is fitted with levelling screw and spirit level.

With cobalt steel needle, 10 cm long, graduated quadrant fully rotatable on metal base marked every 45 degree.

Metal, Painted, wih spout

Polished, 300 x 13 mm length x diam.

Containing 25 expendable steel springs, 2 wide steel springs, 114 x 75 mm diam, 2 soft latex foam blocks, reels of copper wire, one of 32 swg & two of 26 swg, each 50 g, 1 length valve latex tube, 4 elastic cords with eyelets and 4 soft erasers for twisting.

A: With detachable 'snap-on bakelite cover, metal thread terminals, silver contacts. Dome gang dia. 75 mm approx. For use on 3 to 4.5V AC/DC supplies.

B: As above, but works on 230 Volts AC/DC, 50-60 Hz.

Specification.

On stand, with insulated base

Iron, U core, circular section, with flat ends, has one bobbin in each limb wound with enamelled copper wire, with armature.

Comprising one electroscope, one packet of metal leaves, 4 metallised spheres, 1 reel of nylon thread,two polythene plates 75 x 75 mm, one electrophorus plate with insulating handle, 1 proof plane. two aluminium cans, one cellulose acetate strip, 1 polythene strip, one stirrup for suspending strips, one flannel rubber, one wire hook and instructions.

To demonstrate different conductivities of different metals. Rods of 5 different metals and wood, fitted along one side of a metal tank.

Two cast metal uprights, height 18 cm, fitted with two nickel plated rods supporting expansion bar of length 38 cm. Expansion bar is fixed to one upright and moves a pointer on the other, when heated. With scale reading0 to 90°, supplied with one each aluminium, brass and iron expansion bars.

For demonstrating the different thermal expansions of various liquids.

Comprising five bulb tubes with plastic scales, mounted in a frame and supported in a water trough 240 x 108 x 77 mm deep.

The frame has clamps to secure it to the trough and two cross members, the lower cross member having holes, and the upper tubules to locate the bulb tubes.

Dimensions overall 240 x 115 x 460 mm high approx. Bulb diameter 35 mm. Bulb stem 400 mm. Supplied complete with glass bulbs and scale.

Insulated with crocodile clip at each end which will accomodate a 4 mm plug.

Length	Colour
300 mm	Black
300 mm	Red
500 mm	Black
500 mm	Red
900 mm	Black
900 mm	Red

As above with 4mm. Plug at both ends.

For demonstrating magnetic replusion. Comprises six ceramic ring magnets around a rod fixed on a base.

About 20 cms in dia by 44 mm wide turned and carefully balanced, mounted on a horizontal shaft, held in ball bearings. The wheel is marked and pointer is fixed to the bracket. The bracket has four holes and can be fixed to the wall also.

For parallelogram and polygon of forces. A strong drawing board 750 x 600 mm, fitted with brackets for fixing to a wall. Clear space is left all round the edges for attachment of pulleys etc., supplied with pulleys, cords but without masses.

With moulded captive head, 4mm. Socket, nuts and washers. The screw top will clamp ordinary connecting wires and spade terminals. Color: Black, Red

To convert ordinary screw terminals for use with 4 mm plug connectors. This adapter consists of a standard type of spade terminal with an insulated 4 mm. Screw-on hard plastic socket connector.

A: Charged porous pot 150 x 60 mm height x diameter, with brass terminal, having e.m.f. 1.5 volts and zinc rod 12.5 mm diameter in rectangular polythene jar. B: As above, but in glass jar.

Clear glass, ground edges.