A planetary gearbox decrease drive is a mechanical device to shift rotational quickness. A planetary reduction drive is a little scale version using ball bearings in an epicyclic arrangement instead of toothed 
gears.
Reduction drives are used in engines of all kinds to increase the quantity of torque per revolution of a shaft: the gearbox of any car is a ubiquitous exemplory case of a decrease drive. Common home uses are washers, meals blenders and window-winders. Reduction drives are also used to diminish the rotational swiftness of an insight shaft to an appropriate output speed. Reduction drives could be a gear train style or belt driven.
Planetary reduction drives are usually attached between your shaft of the variable capacitor and the tuning knob of any radio, to allow great adjustments of the tuning capacitor with soft motions of the knob. Planetary drives are found in this situation to avoid “backlash”, making tuning easier. If the capacitor drive has backlash, when one attempts to listen in a station, the tuning knob will feel sloppy and it will be hard to perform small adjustments. Gear-drives can be made to have no backlash through the use of split gears and spring tension however the shaft bearings have to be very precise.