Filter classification  

The wave filter was first invented by GA Campbell and O.I.Lobel of Nokia Bell Labs. A filter is a reactive network that  passes the desired frequency band unimpeded, while almost completely rejecting all other bands. The filter is made up of purely reactive elements. Otherwise, the passband attenuation of the filter network will never be zero. Filters differ from simple resonant circuits in that they provide essentially constant transmission over the entire band  they accept. This bandwidth can be between any limits, depending on your design. Ideally, the filter should not produce  attenuation in the desired band, called the transmission or passband, but provide complete or infinite attenuation in all other frequencies, called the attenuation  or stopband. The frequency that separates the transmission band from the attenuation band is defined as the cutoff frequency of the wave filter and is represented by fc. Filter networks are widely used in communication systems to separate the various voice channels of carrier frequency telephone lines. Filters also apply to instrumentation, telemetry equipment, etc. When you need to transmit or attenuate a limited transmission, or when you need to attenuate a limited range of frequencies. The filter can, in principle, have any number of passbands separated by the decay band. However, they fall into four common types. Low pass, high pass, band pass and band removal.  

Silence  

The attenuator is a two-port resistance network  used to reduce the signal level by a specified amount. Many applications require the introduction of a specific loss between the source and the matched load without changing the impedance ratio. Attenuators can be used for this purpose. The attenuator can be symmetrical or asymmetric and can be a fixed constant damping attenuator  called a pad. The variable attenuator is used as a volume control for the broadcast section. Attenuators are also used in the lab to get small  voltage or current readings to test the circuit. The increase or decrease in performance due to the insertion or replacement of proximity elements in the network can be easily expressed in decibels (db) or nepal. That is, the attenuation is expressed in decibels (db) or nepal. Balancer  

An equalizer is a network designed to compensate for the distortion that occurs in a signal as it passes through the electrical network. In general, every electrical network has attenuation distortion and phase distortion. Attenuation distortion is caused by the non-uniformity of attenuation with respect to frequency characteristics.