shenzhen baichuan electronics
The instrument is mainly used to measure and sort the sensitivity and working current of the electret microphone at two frequencies of 1000Hz and 70Hz. The sensitivity of 1000Hz and 70Hz is indicated by two pointers of a double-pointer meter respectively (the black pointer indicates 1000Hz and the red pointer indicates 70Hz). The working current of the electret microphone is directly indicated by an ammeter. Because the electret microphone tester adopts a double-pointer ammeter with a large open surface, it can easily and accurately read out the voltage values at two frequencies of 1000Hz and 70Hz, and quickly measure the performance of the electret microphone.
The instrument has the characteristics of convenient use, accurate testing, and fast speed. It is especially suitable for electret microphone production lineman technical indicators:
- The sensitivity test is divided into three grades:60 dB — 40 dB50 dB ～ 30db40 dB ～ 20db
2. Test accuracy: + – 0.5dB
3. Working current range of electret microphone: 0 ~ 1mA, accuracy 2.5%
4. Working voltage of electret microphone: 1.5V 2V 2.5V 3V 4.5V 6V
accuracy + – 2%
5. Working load resistance of electret microphone: 680 ohm 1K ohm 1.5k ohm 2K ohm 2.2k ohm 3K ohm accuracy + – 1%
6. Test signal frequency: 1000Hz 70Hz accuracy + – 1.5% + – 1 word
7. The working voltage of the instrument is 220V + – 5% / 50Hz, and the power consumption is about 15W
Easy operation
1. When the machine is not turned on, check the appearance, adjust the mechanical zero position of the meter head (generally, it is not necessary to adjust, but it has been adjusted when leaving the factory), and insert the test probe (on the panel) and the acoustic cavity (the acoustic cavity socket is on the back of the instrument), turn on the power and preheat for five minutes. Turn the 1kHz and 70Hz knobs (the two knobs at the bottom of the panel) counterclockwise to the minimum
2. According to the working parameters of the electret microphone, set the working voltage, load resistance, test frequency (point frequency or mixing) and select the range switch * (the secondary switch generally selects the middle position).
3. Then put the standard electret microphone on the appropriate test space of the acoustic cavity,
4. Use the test probe to test the standard electret microphone (pay attention to the positive and negative electrodes, the marked end of the test probe is the negative electrode), and the ammeter has a current display.
5. Keep the test probe test standard electret microphone still, and slowly rotate the 1kHz and 70Hz knobs. The reading of the gauge needle is the same as the data of the standard electret microphone, and the calibration is completed.
6. Place the electret microphone to be measured for the test.
Simple operation
1. Without powering on the instrument, check the appearance, adjust the mechanical zero position of the meter head (generally do not need to be adjusted, it has been adjusted at the factory), insert the test meter pen (on the panel) and the sound cavity (the socket of the sound cavity is on the back of the instrument), turn on the power and warm up for five minutes. 1KHZ and 70HZ knob (the bottom two knobs on the panel) twisted counterclockwise to the minimum!
2. According to the electret microphone working parameters set the electret microphone working voltage, load resistance, test frequency (point frequency or mixing frequency) and select a good range switch * (the second switch generally choose the middle position).
3. Then put the standard electret microphone in the acoustic cavity on the appropriate test empty.
4. Use the test meter pen to test the standard electret microphone, (pay attention to the positive and negative poles, the test pen has a marking end for the negative pole), the ammeter has a current display.
5. Keep the test pen to test the standard electret microphone does not move, while slowly rotating the 1KHZ and 70HZ knob, the meter needle readings and standard electret transmission microphone data is the same, the end of calibration.
6. Place the need to measure the electret microphone test.