Campus Cable TV System Design 20

1.Digital front-end, or analog + digital front-end. It can be watched on a regular TV.

2.I don't understand what you mean by the second question, in fact, all channels have to be modulated to RF. Otherwise, there is no way to transmit it.

As for reducing mutual interference, that is the essential work of the modulator, as long as the channels are reasonably arranged, do not repeat, and try to avoid the frequencies with serious interference of secondary and tertiary beats. In addition, the high-quality modulator is a fixed channel, and a certain channel needs to be customized from the manufacturer when purchasing. If your network is not very large, you can use a jet frequency modulator, which has a low degree of out-of-band rejection and will affect other channels, and occasionally use one or two to have no obvious impact.

The lower limit frequency of the channel is divided according to the division of China's electric channel, and it can be above 50m, depending on the specific situation. If your network is a two-way network, that's a different story. Depends on your uplink and downlink splitting frequency.

3, you don't have a third.

4.The mixer can be used using a normal passive mixer, since you are only mixing in four ways, there is no need to consider gain, and at the same time, it does not produce other nonlinear distortion. There is no damage to the signal, and you can even use the quad splitter upside down.

5. The signal strength can only be measured by an instrument, which is called a field strength meter. The signal strength can be adjusted and controlled by the modulator, which is common to the modulator, if it is too small, it can only be amplified with the amplifier. For where to use in your question, it's best to use a single-channel amplifier.

6.Satellite dishes have actually solved your problem, if you have to open the program, you can install a fixed channel TV antenna for the TV station you want to accept, in this case you need to use a demodulator, and then add a modulator (or just a channel converter). Because the received signal generally cannot be transmitted locally, co-channel interference will occur.

7.You're asking for a broadcast control station. The most basic requirements are also analog-to-digital conversion, format conversion, digital-to-analog conversion, you can ask the computer vendor, there should be many ways. In addition to large-capacity hard disks, it is also necessary to have powerful memory and express, and have powerful corresponding software.

First of all, confirm whether to introduce external network signal sources, such as cable TV signals and satellite signals

Literally, it should be a CCTV network, which is only used on campus and is not open to the public

But why do you only have 5 channel numbers when you transmit 10 signals, you probably mean 10 terminals and 10 outputs?? Keeping the programs of channel 25-30 introduced by the extranet?

The question is vague and unclear, does the campus cable TV network use satellite programs to build its own front-end? If you want to transmit several sets of programs, the channel settings are: 1ch, 2ch...

I don't understand the meaning, do you want to keep d25-d30?

It's very simple, just buy an ordinary TV card. Plug it directly into the PCI slot of the computer, install the included software, and connect it to the cable to watch cable TV. Computer accessories are sold everywhere.

1 amplifier, to 407 distribution, to 4 410, amplifier test port (minus 20db) and then one way is enough for 25 rooms, very simple, it should be noted that the amplifier input is not less than 65, the amplifier amplifies the 30db signal, and the decreasing end of the layer is not lower than about 60, after all, the analog requirements are not so high.

Please take a look at the campus TV station construction plan: campus TV station live broadcast, recording and broadcasting plan.