The models 524-M and 525-M are mantel models housed in attractively designed moulded cabinets, which are produced in three colours: Ivory, Walnut and Burgundy. Features of design include: Tropic-proof construction, automatic volume control, magnetite cores in I.F. transformers and broadcast oscillator coils, air-dielectric trimming capacitors. Electrically, model 524-M closely resembles the models 5I2-M/5I9-M, differences being in the addition of a power switch on the volume control (R8) and a capacity to mains aeri-al. (See circuit diagram and code.) For all other information, refer to the 5I2-M/5I9-M Service Manual. Model 525-M is the same as model 518-M, except that the power switch is situated on the volume control (RIO). Refer to the model 510-M Service Manual for all other information.