SPECIFICATIONS for SPEAKER TEST OSCILLATOR Model OG-484
1. GENERAL DESCRIPTION The OG-484 speaker test oscillator is specially designed to test loudspeakers. The oscillator allows manual and automatic sweeping of the oscillation frequency. Automatic start sweeping and repetitive sweeping are available for automatic sweeping. The oscillator is equipped with a 50 W power amplifier in it to drive a speaker with a load impedance of 1.5 Ω to 8 Ω. 2. CHARACTERISTICS 1) The OG-484 provides manual and automatic sweeping modes. In the manual and automatic sweeping, the output voltage can be changed to preset levels at the preset frequency points. 2) The OG-484 includes a 50 W high-power amplifier which can be connected to a low impedance load of 1.5 Ω to 8 Ω. 3) Provided with protective circuit for an output short-circuit. This circuit will cut the output signal when a shorting should occur across the speaker output terminals carrying an output voltage of 300 mv or greater. In addition, a built-in output relay will make the output terminal open. 4) A unique endless rotary frequency sweeping dial is equipped to allow a highly faithful manual sweeping. This unique dial design eliminates a clicking noise which is generated with a conventional oscillator whenever the rotary dial is moved through the frequency free arc area. 5) With the automatic start sweeping mode, a sweeping automatically starts from the preset frequency point when a speaker to test is connected to the output signal terminal. Sweeping continues until the speaker is disconnected. The sweep starting frequency is automatically restored to the preset point upon speaker disconnection. 6) A digital indicator shows the oscillation frequency or output voltage as selected with a switch. The digital indicator has an auto-ranging capability. 3. PERFORMANCE Operation Modes There are four modes. 1) Full Manual The oscillation frequency is manually swept with the rotary dial in the range from 10 Hz to 20 khz. 2) Step Manual The oscillation frequency is manually swept with the rotary dial changing the output voltage to preset levels at preset frequency points. 1
3) Step Sweep The oscillation frequency is automatically swept changing the output voltage to preset levels at preset frequency points. 4) Preset This mode is used when frequency and output voltage level of above-mentioned 2) and 3) are set. Frequency Points to Set --- See the chart below. Four Points: START F., F1, F2 and STOP F. Output Voltages to Set--- See the chart below. Three Steps: V1 (from START F. to F1), V2 (from F1 to F2) and V3 (from F2 to STOP F.) V1 Step Mode Function Chart V2 V Output Voltage START F. F1 F2 STOP F. Frequency Power Amplifier 1) Max. Output Wattage and Voltage: 50 W, 20 V (connection to a load of 8 Ω) 2) Max. Output Wattage at a Variety of Load Impedance: Max. Output Wattage Load Output Voltage 1.5 Ω 8.66 V 50 W 2 Ω 10.0 V 4 Ω 14.1 V 8 Ω 20.0 V 3) Min. Output Wattage: 0.1 W 4) Load Impedance: 1.5 Ω or greater 5) Sweeping Frequency Range: 10 Hz to 20 khz 6) Output level Deviation: ±0.5 db in 100 Hz to 10 khz ±1.0 db in 10 Hz to 20 khz 2
Oscillator 1) Oscillation Frequency Range: 10 Hz to 20 khz 2) Distortion (THD): Within 0.20% in 100 Hz to 1 khz at 8Ω 50 W output Within 0.30% in 10 Hz to 10 khz at 8Ω 50 W output Within 0.40% in 10 Hz to 20 khz at 8Ω 50 W output Within 0.30% in 100 Hz to 1 khz at 1.5Ω 50 W output Within 0.60% in 10 Hz to 10 khz at 1.5Ω 50 W output Within 0.90% in 10 Hz to 20 khz at 1.5Ω 50 W output 3) Frequency Dial Accuracy: ±(8% + 2) Hz To be obtained by manual sweeping with the one-range dial with logarithmically calibrated scale. 4) Sweeping Function: Repetitive sweeping with an automatic start sweeping. 5) Sweeping Time: Adjustable from 0.5 s to10 s (in the sweeping frequency range of 10 Hz to 20 khz) 6) Pause Time: 150 ms ±10 ms 7) Settable Start Frequency Range: 10 Hz to 20 khz 8) Settable Stop Frequency Range: 10 Hz to 20 khz 9) Auto Start Trigger Voltage: 0.1 V or greater (at a load of 1.5 Ω to 8 Ω) 10) OSC Line Output Voltage: 2.4 V ±20% at 20 V output range and the potentiometer set to max., keeping the output signal terminals open. 11) OSC Line Output Impedance: 600 Ω ±10% Digital Indicator 1) Output Voltage Indication Error: Display: 3-1/2 digits with auto-ranging function Indication Error 199.9 V 19.99 V ±(3% + 2) digits 1.999 Error: V ±(3% + 2) digits 2) Oscillation Frequency Indication Error: Display: 3-1/2 digits with auto-ranging function Indication Error 199.9 khz 19.99 khz ±(3% + 2) digits 1999 Hz 199.9 Hz ±(3% + 10) digits 3
Operating Temperature Humidity Ranges 5 C to 40 C 5% to 90% RH (with no condensation) Power Requirements Power Consumption AC 100, 120, 200, 220 or 240 V 50/60 Hz 250 W One of power voltages must be specified when ordering so that transformer tap arrangement can be done at the factory before shipment. Dimensions and Mass 352 (W) 152 (H) 370 (D) mm, excluding extrusions 15 kg Accessory Power cord 1 pc. 4. External View (Front Panel) (Rear Panel) We reserve the right to change specifications without notice for improvement. 4