Pioneer XD-J110 - volume control board - Alps ACX1053-A-8130

A motorized potentiometer combines a

potentiometer A potentiometer is a three- terminal resistor with a sliding or rotating contact that forms an adjustable voltage divider. If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat. The measuring instrum ...

with an

electric motor An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a electromagnetic coil, wire winding to gene ...

Uses

Motorized potentiometers can be found in audio/video equipment, specifically

mixing console A mixing console or mixing desk is an electronic device for Audio mixing (recorded music), mixing audio signals, used in sound recording and reproduction and sound reinforcement systems. Inputs to the console include microphones, signals fro ...

s. In this application, they are called ''motorized faders''. Mixing consoles with motorized faders typically are used to save and restore settings on the same console and sometimes to transfer settings to a different console. Save and restore also allows to control more channels then there are sliders by switching which tracks are controlled.https://thehomerecordings.com/mixers-motorized-moving-faders/ While historically, the faders where literal motorized potentiometers, nowadays faders may directly digitize the fader position and apply the value digitally in the digital signal processing. Motorized potentiometers are used in industrial controls.Selco E7800 Motorized Potentiometer Specifications
/ref> Motorized potentiometers may be used for remote control applications.coudoint: Motorized Potentiometers and Rheostats
/ref> Motorized potentiometers can be used to build electrical/electronic

analog computer An analog computer or analogue computer is a type of computation machine (computer) that uses physical phenomena such as Electrical network, electrical, Mechanics, mechanical, or Hydraulics, hydraulic quantities behaving according to the math ...

s. The motorized potentiometer can act as a computing element, but also as a way to convert a physical into an electrical value. Radio control servo motors use a potentiometer as feedback for the servo position.

Features

Some motorized potentiometers allow both manual and motorized operation. Motorized potentiometers can be slide or rotary potentiometers. There also exist multiple turn motorized potentiometers. The end of travel may be detected using

limit switch A limit switch with a roller-lever operator; this is installed on a gate on a canal lock, and indicates the position of a gate to a control system upA limit switch mounted on a moving part of a bridge In electrical engineering, a limit switch ...

es, a peak in motor current as the mechanism stalls, or a separate resistive element used for position feedback.

History

Given that the history of the motorized potentiometer is linked to electronic analog computers, and electronic analog computers to military use, recording keeping and publication were limited, also meaning that parallel invention was highly likely. The

M9 Gun Director The M9 gun director was an electronic director developed by Bell Labs during World War II. This computer continuously calculated trigonometric firing solutions for anti-aircraft weapons against enemy aircraft. When cued by the SCR-584 centimet ...

had a potentiometer controlled by

op amp An operational amplifier (often op amp or opamp) is a DC-coupled electronic voltage amplifier with a differential input, a (usually) single-ended output, and an extremely high gain. Its name comes from its original use of performing mathema ...

s. The ''Bomben-Abwurfrechner BT-9'' has a motor driven potentiometer to convert a pressure into a potentiometer setting.Historische Militär-Rechner: Bomben-Abwurfrechner BT-9 des HUNTER (ein SAAB-Export-Produkt), page 12
/ref> In 1968 a patent was filled describing a motor-potentiometer combination where the motor only engages when energized, allowing manual operation. In 1970 a patent was filled describing a motor-potentiometer with overload clutch and interchangeable gear ratio.

Manufactures

Manufactures are for e.g.

Alps Electric , previously known as is a Japanese multinational corporation, headquartered in Tokyo, Japan, producing electronic devices, including switches, potentiometers, sensors, encoders and touchpads. The company was established in 1948 as Kataoka El ...

.ALPS RK27112MC Specification
/ref>

References

{{Reflist Resistive components Analog computers