BIRDMAN® watches are equipped with the finest Swiss RONDA electro-mechanical movements, hand crafted, tested and built to withstand hostile elements like shocks, water molecules, dirt, pressure, heat and cold.
In the following some basic info about your instrument.
Any timekeeping device will contain at least three different parts: a drive mechanism, an escapement device (way of measuring time), and a method of display. A windup alarm clock, for example, uses a tension spring as a drive mechanism, an escapement wheel, and the gear driven mechanical hands moving across the clock face as a display of the time.
Generations of timepieces through history have worked to improve accuracy. Early mechanical clocks used falling weights as drive devices and a verge and foliot as an escapement device. The verge was a gear tensioned by a weight and the foliot was a ratchet type device that oscillated back and forth on the verge in a hold release pattern creating the familiar tick tock sound of clocks. Escapement wheels in mechanical clocks of today use much the same concept. The discovery of the pendulum by Galileo provided an even more accurate method of timekeeping as the frequency of the pendulum’s swing is not affected in time by its amplitude. In other words, even as the pendulum’s swing weakened in amplitude, the frequency between cycles remained constant.
Having a timepiece that was portable also had its challenges. Pendulum clocks don’t work well in motion. Spring driven clocks give portability, but run faster when newly wound and progressively slower as the spring relaxes. Electric clocks were an improvement, but with still relatively low frequency escapement at 60 cycles per second, were not extremely accurate.
Quartz timepieces use the nature of the quartz crystal to provide a very accurate resonator which gives a constant electronic signal for timekeeping purposes. Quartz crystals are piezoelectric, which means that they generate an electrical charge when mechanical pressure is applied to them. They also vibrate if an electrical charge is applied to them. The frequency of this vibration is a function of the cut and shape of the crystal. Quartz crystals can be cut at a consistent size and shape to vibrate at thousands of times per second, making them extremely stable resonators for keeping very accurate time.
Although the piezoelectric effect of quartz crystals had been understood since the 1880s, the first application of this quartz property in the use of a time piece didn’t occur until 1927. It was in that year that the original quartz clock was invented by W.A. Marrison and J.W. Horton. Their quartz clock was a very large device as compared with today’s quartz wristwatches which also use microchip and liquid crystal. The basic principle behind all watches and clocks is a device that oscillates at a fixed frequency. Early mechanical watches and clocks used a pendulum or springs with some form of regulator to keep the frequency fixed. Time is simply measured by counting these oscillations. A simple device might oscillate at 1Hz (once per second), therefore 1 second would elapse for each oscillation.
Quartz watches began to appear in the early 1970s. They use a crystal of quartz (silicon dioxide) shaped like a small bar. This is a 'piezoelectric' material - when bent or compressed it generates a small electric field (and vice versa).
The crystal is formed to have a natural oscillation at around 32,000Hz. These oscillations generate small electrical signals which are 'divided down' by the circuit within the watch to the required frequency (usually seconds) and translated into pulses which are sent to the watch display or a motor to move the seconds hand.
The advantage of quartz watches is their simplicity and accuracy - crystals maintain their frequency over broad operating conditions and are cheap to make.
Higher accuracy devices generally use a material with even higher frequencies (again the frequency must be as stable as possible). Atomic clocks count the oscillations between the nucleus and the electrons in an atom (typically cesium) which oscillate at around 9 billion Hz.
All our watches are fitted with sapphire crystal. The crystal is cut from the polished slice of solid sapphire that has been created by fusion and crystallization of alumina. Sapphire is so hard that only diamond can scratch it.
The relative stability of the resonator and its driving circuit is much better than its absolute accuracy. Standard-quality resonators of this type are warranted to have a long-term accuracy of about 6 parts per million at 31 °C (87.8 °F): that is, a typical quartz wristwatch will gain or lose 15 seconds per 30 days (within a normal temperature range of 5°C/41°F to 35°C/95°F) or less than a half second clock drift per day when worn near the body.
ISO 1413 shock-resistant standard
Shock resistant is a common mark stamped on the back of wrist watches to indicate how well a watch copes with mechanical shocks. In a mechanical watch, it indicates that the delicate pivots that hold the balance wheel are mounted in a spring suspension system intended to protect them from damage if the watch is dropped. One of the earliest and most widely used was the Incabloc system, invented in 1934. Before the widespread adoption of shock resistant balance pivots in the 1950s, broken balance wheel staffs were a common cause of watch repairs.
Virtually all mechanical watches produced today are shock resistant. Even divers' watches (according to ISO 6425) must correspond not only with such criteria as water resistance, luminosity, magnetic resistance and strap solidity, but also shock resistance.
The International Organization for Standardization issued a standard for shock resistant watches, which many countries have adopted. ISO 1413 Horology—Shock-resistant watches specifies the minimum requirements and describes the corresponding method of test. It is intended to allow homologation tests rather than the individual control of all watches of a production batch. It is based on the simulation of the shock received by a watch on falling accidentally from a height of 1 m on to a horizontal hardwood surface.
In practice shock resistance is generally tested by applying two shocks (one on the 9 o'clock side, and one to the crystal and perpendicular to the face). The shock is usually delivered by a hard plastic hammer mounted as a pendulum, so as to deliver a measured amount of energy, specifically, a 3 kg hammer with an impact velocity of 4.43 m/s. The watch must keep its accuracy to +/- 60 seconds/day as measured before the test.
ISO 2281 water-resistant watches standard
Water Resistant is a common mark stamped on the back of wrist watches to indicate how well a watch is sealed against the ingress of water. It is usually accompanied by an indication of the static test pressure that a sample of newly manufactured watches were exposed to in a leakage test. The test pressure can be indicated either directly in units of pressure such as bar (which is neither an SI nor an cgs unit, but is accepted for use and used by the International Organization for Standardization), atmospheres, or (more commonly) as an equivalent water depth in meters (in the United States sometimes also in feet).
An indication of the test pressure in terms of water depth does not mean a water resistant watch was designed for repeated long-term use in such water depths. For example, a watch marked 30 meters water resistant cannot be expected to withstand activity for longer time periods in a swimming pool, let alone continue to function at 30 meters under water. This is because the test is conducted only once using static pressure on a sample of newly-manufactured watches. The test for qualifying a diving watch for repeated usage in a given depth includes safety margins to take factors into account like aging of the seals, the properties of water and seawater, rapidly changing water pressure and temperature, as well as dynamic mechanical stresses encountered by a watch. Also every diving watch has to be tested for water resistance or water-tightness and resistance at a water overpressure as it is officially defined.
The International Organization for Standardization issued a standard for water resistant watches which also prohibits the term waterproof to be used with watches, which many countries have adopted. The international standard ISO 2281 Horology – Water-resistant watches defines the water resistance of watches. This standard was introduced in 1990 and only designed for watches intended for ordinary daily use and are resistant to water during exercises such as swimming for a short period. They may be used under conditions where water pressure and temperature vary. However, whether they bear an additional indication of overpressure or not, they are not intended for submarine diving.
The ISO 2281 standard specifies a detailed testing procedure for each mark that defines not only pressures but also test duration, water temperature, and other parameters. Besides this ISO 2859-2 Sampling plans indexed by limiting quality (LQ) for isolated lot inspection and ISO 2859-3 Sampling procedures for inspection by attributes – Part 3: Skip-lot sampling procedures concerning procedures regarding lot sampling testing come into play, since not every single watch has to be tested for ISO 2281 approval.