â·ÃÊͺ¶ÒÁÃÒ¤Ò à¤Ã×èͧÇÑ´¤ÇÒÁ´Ñ§àÊÕ§ à¤Ã×èͧÇÑ´àÊÕ§ Sound Meter > à¤Ã×èͧÇÑ´ÃдѺ¤ÇÒÁ´Ñ§àÊÕ§ Sound Level Meter Extech 407750 Sound Level Meter with PC Interface à¤Ã×èͧÇÑ´ÃдѺ¤ÇÒÁ´Ñ§àÊÕ§ Sound Level Meter Extech 407750 Sound Level Meter with PC Interface Big backlit display, PC Interface & background sound absorber "High accuracy meets ANSI & IEC 651 Type 2 standards" High accuracy meets ANSI & IEC 651 Type 2 standards Background noise absorber for machine noise measurements filters ambient noise RS-232 interface for capturing data directly on a PC Large display with backlighting and analog bargraph Min/Max Analog AC/DC outputs for connection to a recorder Tripod mount ideal for field use Specifications: Digital Display: 3-1/2 digit (1999 count) Autorange LCD Bargraph Display: 50dB display range (1dB resolution) Measurement Range: 30 to 130dB (35 to 130dB for "C" weighting) Resolution: 0.1dB Accuracy: +/-1.5dB @ 94dB for a 1kHz sine wave Microphone: Electret Condensor .24" (6mmdia.) type Frequency Weighting: "A" and "C" type Time Response: Slow/Fast Sampling time: updates every 0.5 seconds Measurement frequencey range: 31.5Hz to 8KHz Analog output: AC: 0.707Vrms (full scale); DC 10mVDC/dB Applicable Standards: IEC 651 Type 2, ANSI S1.4 Type 2 Power Supply: 9V battery, optional AC adaptor Dimensions: 10x3.1x1.5" (256x80x38mm) Weight: 8.5oz (240g) 407750 Extech Sound Meter à¤Ã×èͧÇÑ´ÃдѺàÊÕ§ à¤Ã×èͧÇÑ´àÊÕ§