Common problems in the use of conference system

1. Maintenance of projector

In the use of projector, the most important problem is to keep good heat dissipation. The projector has two power switches, one is the soft switch (power key) and the other is the hard switch (power switch). After the use of the projector, first press the power key to turn off the projector. In fact, the projector is not really finished at this time, and the cooling fan on one side is still rotating. Because the heat released by the projector is huge, the manufacturer has designed a three to five minute cooling process. If the projector is turned off at this time, the internal heat cannot be discharged, and the LCD or bulb will be burned. Turn off the hard switch after the fan stops rotating. In general, the projector should be closed for four or five hours after a continuous use, so that it can rest. This will extend the service life of light bulbs and LCD panels. Do not vibrate the projector during projection.

2. The screen color of projector is different from that of display

When the color of the projector screen is different from the color of the display, it is possible that the VGA cable is not connected properly or a cable of a certain color is dropped inside, in addition, the LCD board may be burnt out.

3. Some characters of the projector are not completely displayed on the screen

When some characters of the projector are not completely displayed on the screen, it is possible that the resolution of some projectors is not enough, the display of characters and graphics is not complete, and the resolution of the computer can be reduced to see whether it will be completely displayed. If not, one of the three LCD chips has been burnt out.

4. The projector appears dark yellow or the color is not full

If the projector appears dark yellow and the color is not bright. It may be that the life of the bulb is over, and the bulb shall be replaced (it is worth noting that the service time of the bulb shall be reset after replacement, otherwise the new bulb will be easily aged according to the old time.

5. Can I use two microphones of the same frequency at the same time

Cannot be used at the same time. Wireless transmission cannot be “mixed” in the air. Even at the same frequency, the receiver cannot mix two transmission signals. For example, it is impossible for two FM radio stations to send signals on the same frequency. Because this will cause confusion, resulting in audio distortion. All in all, each wireless transmitter should have a separate receiver with its own frequency.

6. What is the frequency difference between wireless microphones to avoid interference?

It depends, but at least 4MHz. We can’t answer this question explicitly here, because it involves complicated calculation. In general, the frequency gap required by cheaper wireless systems is large, because their receivers are simple in design and few in selection. This limits the number of channels it is compatible with. The system with higher price has better filtering performance, closer distance between channels, and more compatible channels. If we say “you don’t want to make your own calculations”, we must be right. If you need, please contact the manufacturer or agent, they will help you calculate. Most manufacturers have calculated the compatible frequencies for each of Shure’s wireless features, so you don’t have to do these tedious mathematical calculations yourself.

7. UHF is better than VHF, right?

These two frequency bands for wireless microphones have their own advantages and disadvantages. This is determined by the users of the frequency band, the physical characteristics of the frequency band, and the adjustment limit of the frequency band.

The following are the advantages of UHF over VHF:

? UHF band is not “crowded” with VHF band.

? UHF with flexible frequency is widely used.

? UHF features provide more compatible systems. [for example, Shure LX and SC (VHF band) systems can only provide 12 compatible channels, while Shure UHF band systems can provide more than 100 compatible channels. ]

? UHF system has higher power output than VHF, wider frequency shift, better dynamic range and better signal-to-noise ratio.

VHF is superior to UHF in several aspects:

1. VHF system is cheaper.

2. VHF has a larger transmitting range under a specified transmitting power.

3. VHF signal transmission, even through non-metallic materials. VHF has a long wavelength and is not easily absorbed by human body.

8. Can UHF system be compatible with VHF system?

Yes, UHF can be compatible even if the maximum number of compatible VHF systems is used. (however, the current VHF antenna, VHF separator or VHF antenna distribution amplifier of UHF receiver cannot be connected.).