Vacuum Tube

The **Vacuum Tube** is a glass tube that has its gas removed, creating a vacuum. Vacuum tubes contain electrodes for controlling electron flow and were used in early electronic devices as a switch or an amplifier. On Earth, vacuum tubes are considered as generally outdated technology due to the introduction of bipolar transistor, field-effect transistor as well as the usage of integrated circuitry, but in the New World, they are considered as the key component to all electronic devices in the Gra Valkas Empire.

## Overview

A vacuum tube consists of two or more electrodes in a vacuum inside an airtight envelope. Most tubes have glass envelopes with a glass-to-metal seal based on kovar sealable borosilicate glasses, though ceramic and metal envelopes (atop insulating bases) have been used. The electrodes are attached to leads which pass through the envelope via an airtight seal.

## Uses

The Gra Valkas Empire has access to World War 2 level electronic technology which includes radio, radar, television, and primitive calculating devices. Radio and radar are heavily used in military communication and early warning systems. Television makes use of a cathode ray tube, which allows images and sound to be transmitted and received. Calculating the distance, speed, and angle of naval guns is done by computing devices similar to the Eniac machines of the 1940s. Any electrical devices that utilize heat and light also make use of the vacuum tube.

## Disadvantages

* Bulky, hence less suitable for portable products.
* Higher operating voltages generally required.
* High power consumption; needs heater supply that generates waste heat and yields lower efficiency, notably for small-signal circuits.
* Cannot handle high-performance or high-speed computations
* Glass tubes are fragile, compared to metal transistors.
* Sometimes more prone to microphonics than transistors, depending upon circuit and device.
* Cathode electron-emitting materials are used up in operation.
* High-impedance devices that need impedance matching transformer for low-impedance loads, like speakers; however, the magnetic cushion provided by an output transformer prevents the output tubes from blowing up.
* Sometimes higher cost than equivalently powered transistors.

* Short lifespan compared to transistors
* Generates large amounts of heat which can damage other components during prolonged or excessive use.

## Gra Valkas Doctrine

Due to the fact that nearly all of their electronic devices are dependent on the vacuum tube along with the chronic lack of imagination and motivation to innovate, the Gra Valkas engineers and the people in general, believe that they have reached the apex of what science can achieve. As such, they believe that if a task cannot be accomplished by their vacuum tube technology, then it is considered as impossible. For example, when the idea of the AEGIS system was presented to the head of the Advanced Technology Research Institute, it was scoffed as impossible and just a huge lie. In their minds, in order to achieve the same computational power of the AEGIS system, they would have to spend 400 years to shrink a vacuum tube to the size of a coin. For them, a computer is a huge, loud and cumbersome device that can fill a whole building floor. Despite being shown an example of advanced technology in the form of an OLED monitor and SD card, since they did not pertain to the military directly, the ambassadors missed the ramifications of how far behind their technology was with Japan's.

As a result of this narrow-minded thinking, the engineers and the military are caught completely off-guard when facing Japan's superior fighters, radar jamming, and especially guided missile technology. Due to the disadvantages of vacuum tube technology, the Gra Valkas Empire finds itself seriously behind and unable to adapt fast enough. Furthermore, their attempts to combat Japan using their vacuum tube technology has so far failed, such as their anti-missile jammer.