7116C provides pure sine wave with very low total harmonic distortion. (approx. 0.1% THD ). The total harmonic distortion of 7116C consists of 2nd Harmonic component only and nearly without higher order harmonic components. So, 7116C is very suitable to test the sound quality ( spurious noise inspection ) of all kinds of loudspeaker, headphone, receivers, piezo, speakers system…etc.
The frequency produced by 7116C is more stable than the ordinary beat frequency oscillator produced. and the sine wave provided by 7116C is purer than the ordinary function generator. Therefore, 7116C has both advantages of low distortion and high stability. do not use the ordinary function generator to test the spurious noise ( rattle and buzz ) of loudspeaker, loudspeaker, receiver, etc.… Because user will easily neglect the prohibited spurious noise caused originally from the high order distortion component of the function generator.
Specification
1. Frequency Range: Cover 20Hz to 20KHz in one range, ( usually under 15Hz and higher than 21KHz ). 2. Frequency Counter: 4 digits display, resolution 1Hz, accuracy ±1Hz. 3. Signal: Sine Wave, THD. < 0.15% ( 1KHz, 10V ), THD. 0.1% typical. 4. Power Output: 7116C ( 20W ) 0- 12.6V 8 OHMS load. ( At rated line 0- 9.0V 4 OHMS load.
voltage ) 7116C ( 60W ) 0- 22.0V 8 OHMS load.
0 - 15.5V 4 OHMS load. 7116C ( 100W ) 0- 28.3V 8 OHMS load.
0 - 20.0V 4 OHMS load. Continuously adjustable with short circuit protection.
5. Voltage Meter: 3 3/4 Digits, autorange ( Two Ranges ). Low Range: 0.000V-3.300V ( Approx. ) Resolution 0.001V High Range: 3.30V-38.00V ( Approx. ) Resolution 0.01V Accurancy: ± 0.6% of reading ±2dgts.
6. Output Protection Circuit: Triple-protection, The amplifier won't be burnt out even if the output terminal is continuously shorted all day long. The output terminal will become an open circuit when the load is shorted, And will have power output again automatically when the shorted condition was vanished. 7. Sweeping Mode: Logarithmic Sweep. 8. Sweeping Width: Maximum ratio is 1:1000, 20Hz to 20KHz in one sweep. 9. Sweep Time: 0.3∼40 SEC., Continuously adjustable. 10. Power Consumption: 7116C ( 20W ) 45VA Max. 7116C ( 60W ) 100VA Max. 7116C ( 100W ) 160VA Max. 11. Min. Loading impedance : must be > 3.2 12. Dimension: 37 ( L ) × 28 ( W ) × 13 ( H ) Cm. 13. Weight: 7116C ( 20W ) 6.0 KGS. Approx. 7116C ( 60W ) 8.0 KGS. Approx. 7116C ( 100W ) 10.0 KGS. Approx.
1. Automatic Sweep Generator : Depress Auto / Manu (8) pushbutton, Then 7116C will sweep forth and back between the frequencies set by start adjustment knobs and stop knob.
2. Manual Sweep Generator : Depress start (3) or stop (4) pushbutton, adjust Start / Stop coarse knob.
3. A Constant Frequency Generator : Depress start (3) or stop (4) pushbutton, And adjust start Coarse / Fine knob (5) / (6) or stop knob (7) to the frequency desired.
Measuring The Lowest Resonant Frequency Fo Of A Loudspeaker
The lowest resonant frequency of a midrange or a tweeter is a very important parameter when designing the speaker system. And the lowest resonant frequency of a woofer would affect the regeneration of low frequency greatly. Therefore, It's necessary to measure the Fo value of each kinds of loudspeaker. And 7116C can measure the Fo value manually.
1. Connect the loudspeaker to the output terminal of 7116C. 2. depress the Fo pushbutton (2). 3. Adjust the output voltage to approximately 0.5V. 4. Adjust the start Coarse / Fine knob, To start at 20Hz up to a higher frequency slowly. ( Especially slowly for the woofer ) The voltage value will increase as the frequency increasing. A maximum voltage should be reached at a certain frequency, And the voltage value will fall down when the frequency goes higher again. Please turn the start Coarse / Fine knob back to the frequency at the highest voltage, And the frequency is the lowest resonant frequency of the loudspeaker at that voltage.
5. In EIA standard, It is recommended to test the Fo value with 1.0V ± 10% voltage across the terminals of the loudspeaker. So user should adjust the voltage volume to 1.0V after the Fo value was found. Then repeat steps 1. to 4, To make sure that the lowest resonant frequency found is exactly at the highest voltage of 1.0V
