The model 534-MB is a mantel model designed for dry-cell battery operation. Battery connections are shown in the accompanying diagram. Features of design include: Tropic-proof construction, automatic volume control, magnetite cores in I.F. transformers and broadcast oscillator coil, air-dielectric trimming capacitors, straight-line edge-lighted plastic dial scale. Chassis Removal. First remove the control knobs by pulling them straight off their spindles. Then remove the cabinet back. It is fastened to the cabinet body by four screws. The chassis is held in the cabinet by four screws through the base of the cabinet. Removal of these enables the chassis to be withdrawn from the cabinet. When replacing the cabinet back make sure that the battery cable passes through the hole provided in the cabinet back.