With interchangeable scales. A versatile instrument and demonstration meter that can be converted to an a.c., or d.c. voltmeter or ammeter with selection of various ranges for each mode. With a high quality moving coil, spring controlled movement with full scale... 

For experiments in diode characteristics. A double diode valve EB91 or equivalent is mounted on a two part plastic box 90x90x30 mm with sockets for two anodes, heater and cathode

Two brass blocks with 4mm insulated terminals are mounted on a moulded base, an accurately tapered plug with a fluted top fits into the tapered hole between the two blocks, ensuring very low contact resistance.

High sensitivity, very useful as null detector. Housed in sturdy plastic case with in-built lamp and scale arrangement, taut band type movement, with Alcomax magnet, clamp and free arrangement for safe transportation, easy replacement of the 6V lamp, working on ...