Table of Contents
How does a stepped attenuator work?
Usually the switches are set up with a gradually increasing amount of resistance on each switch position, which yields a stepped attenuator that gradually lowers a signal level at its output for each subsequent position of the switch.
What is a stepped potentiometer?
A potentiometer uses some type of strip of resistive material, and then a wiper slides across it to provide variable levels. A stepped attenuator, on the other hand, is basically a series of switches, with each position having a specific value of resistor tied across it.
What are the different types of attenuators?
RF attenuators are generally used in electronic circuitry, while optical ones are used in fiber optics. There are essentially six different kinds of RF designs: fixed, step, continuously variable, programmable, dc bias and dc blocking.
Are attenuators bidirectional?
RF attenuators are bidirectional two port passive devices. As its name implies, it attenuates or reduces signal power level while the signal pass through it.
How does a passive preamp work?
Passive Preamplifier In essence is merely a volume control designed to attenuate the signal going from the source (usually a CD player) to the amplifier. Since it is passive, it has no inherent gain because it has no active components (tubes or transistors) in the signal path.
What is a digital step attenuator?
A digital attenuator, unlike variable attenuators, switches in discrete and finite attenuation states. This switching is usually achieved in binary steps. Digital attenuators employ semiconductor devices to achieve each attenuation step.
How many types of attenuators are there?
Attenuators are majorly classified into three types fixed attenuators, variable attenuators and step attenuators.
What is RF attenuator?
RF attenuators are essentially electrical resistors that are put in line with an RF signal and reduce the signal strength by converting some amount of RF energy into heat. The amount of resistance used is what determines the amount of attenuation.
What is the point of a passive preamp?
Can a stepped attenuator be used with a concentric potentiometer?
A true stepped attenuator switches both resistors to maintain constant input and output impedance. This could be done with a dual concentric potentiometer, but would take perfect tracking, most likkely with hand trimming via knife or laser. Tracking is also a major issue in stereo potentiometers.
What are the advantages and disadvantages of a step attenuator?
The advantages of a stepped attenuator are the possibility of better sound because of the parts quality. The downside of this arrangement is the volume is controlled in a series of fixed steps and you may or may not like the step level. There are pots that can come close to the performance of a stepped attenuator, but rarely do they.
What are some common problems with potentiometers?
Tracking is also a major issue in stereo potentiometers. The left and right vary relatively, shifting the balance as you change volume. Stepped attenuators obviate tracking errors.
Why are stepped attenuators used in audio mixing boards?
For many years almost all broadcast audio mixing boards used stepped attenuators for reasons of reliability.