FH -- 2M -- 3/60 SPECIFICATI0NS Type: Moving Coil Dynamic Frequency Response: 35 to 12,000 cycles Output Impedance: Output level: Dimensions: 633A -- 30/50 ohms 633C -- 30/50, 150/250 ohms, selective -- 55 dbm/10 dynes/cm- Length 31/2" Diameter 2" Weight: Finish: Mounting: 633A -- 10 ozs. 633C -- 13 ozs. Instrument gray 5/8" -- 24 thread ACCESSORIES See "Microphone Accessories" sheet for desk or floor stands, on-off switches, adapters, and other microphone accessories. ARCHITECTS AND ENGINEERS SPECIFICATIONS This microphone shall be of the Dynamic Moving Coil type having the following speci- fications. The microphone shall have an aluminum diaphragm with tangential com- pliance and the voice coil shall be aluminum ribbon edge-wound. The frequency response shall be from 35 to 12,000 cycles. At 30 cycles it shall not be more than 6 db down and at 12,000 cycles not more than 8 db down. The microphone shall be available in (choose one) (a) 30."50, or (c) 30/50, 150 '250 ohms, and shall be bal- anced with respect to ground. The diameter of the microphone shall not exceed 2" with a length of not more than 3'/~". The swivel adapter shall have %" -- 24 thread. The microphone shall be so designed as to accept a separate baRle for semi-directional pickup pattern. The microphone only shall weigh not more than 13 ozs. The unit shall be designed to be used with plug, jack, and adapter where specified. The output level of the microphone shall be at least -- 55 dbm 10 dynes/cm-. The microphone shall be Altec Lansing Model 633 (select one) (A) or (C). PRINTED IN U.S.A. AL -- 1430-1