metal rectifier

Hence, metal rectifiers are still manufactured in small quantities today.

The metal rectifier and the frequency changer valve will probably need changing, as with most of these, but that won't break the bank.

A selenium rectifier is a type of metal rectifier, invented in 1933.

I remember the vile stink when I dismantled a blown metal rectifier.

Metal rectifiers were also used as envelope detector (AM demodulator) diodes in radio receivers.

The metal rectifier ages, going high resistance but not keeling over entirely like a valve, reducing the HT, but keeping the set working.

Another early type of semiconductor device is the metal rectifier in which the semiconductor is copper oxide or selenium.

It was used for battery chargers and similar applications from the 1920s until lower-cost metal rectifiers, and later semiconductor diodes, supplanted it.

As solid-state metal rectifiers became available for low-voltage rectification in the 1920s, mercury arc tubes became limited to higher voltage and especially high-power applications.

Before the development of silicon semiconductor rectifiers, vacuum tube thermionic diodes and copper oxide- or selenium-based metal rectifier stacks were used.

The cat's-whisker detectors used in the early days of wireless and metal rectifiers used in early power applications can be considered primitive Schottky diodes.

The principle of operation of a metal rectifier is related to modern semiconductor rectifiers (Schottky diodes and p-n diodes), but somewhat more complex.

Many purpose-designed transformer-rectifier ("Rectiformer") units were specifically designed around the characteristics of metal rectifiers, and substituting silicon rectifiers would necessitate replacing the complete assembly.

As is the case with many other industrial processes, it is often considerably cheaper and more convenient to pay someone to manufacture replacement "legacy" metal rectifiers than to replace the rectiformer.

These are mostly in electroplating, aluminium smelting and similar high-current low-voltage industrial applications, where the lower forward voltage drop of metal rectifiers is more important than their reverse breakdown voltage.

Metal rectifiers have been replaced by silicon diodes in most devices, however there are certain applications where the replacement of metal rectifiers with silicon units has proven impractical.

A number of rectifier discs would need to be used in series to provide an adequate reverse breakdown voltage figure - a bridge rectifier for a 12V battery charger would often use 12 metal rectifiers.

In some countries the term "metal rectifier" is applied to all such devices; in others the term "metal rectifier" normally refers to copper-oxide types, and "selenium rectifier" to selenium-iron types.

Metal rectifiers consist of washer-like discs of different metals, either copper (with an oxide layer to provide the rectification) or steel plated with selenium, interspersed with aluminium discs (which were often of a larger size, to provide cooling).