Siemens 2000

The Siemens 2000 is a 16-mm - film projector provided by the manufacturer Siemens was brought in 1951 to the market.

Application area

It was and is very popular, especially in schools, and is still sometimes used for school films.

origin

The series of Siemens projectors goes back to the 1930s. Even back then there were devices with optical sound.

execution

The robust construction made it the ideal school film device, as it prevented that a new device had to be purchased within a short time if operated by inexperienced operators in school. Due to the modular design, the subsequent conversion of a silent film device into a sound film device was possible within a very short time.

Lamp power

The device offered the possibility of using lamps of different power. This enabled the light output to be adapted to different sized screens. There was a choice of lamp outputs of 250, 375, 500 or 750 watts, which were operated directly on the mains voltage via a series resistor. This also shows the main disadvantage: when using a different lamp strength, it was also necessary to change the lamp series resistor . In addition, there is the high connected load of the device, because when a lamp with 110 volt lamp voltage is operated on the 230 volt mains, the same output of the lamp is again converted into heat at the series resistor. A connected load of 1000 watts is required for operation with a 500 watt lamp. In the versions with a series transformer, the heat load could be reduced considerably. Conversions to halogen lamps are also common. This means that the amount of heat given off can be further reduced with the same light output.

Picture change numbers

As one of the few 16 mm projectors, the Siemens 2000 enables the speed to be set continuously between 16 and 26 images per second using a centrifugal regulator switch; three image change numbers (16, 18 and 24 images / s) can be set precisely using a stroboscope disk. The option of infinitely variable speed control made the device interesting because copies of silent films can also be shown at the appropriate speed.

Aperture number

The aperture can be switched to two or three wings.

asbestos

However, this projector also had some disadvantages: For example, asbestos was used in almost all models - in some cases even directly in the air flow of the fan.

Executions

The Siemens 2000 was available in very different versions: silent film versions, versions for optical sound, for light and magnetic sound with permanently flanged or separate under-bench tube amplifier, with and without sound recording option, as well as devices with a separate tape drive on the back of the projector for dubbing your own film recordings. Later in the 1960s, the tube amplifiers were replaced by transistor amplifiers.

A few years before the Siemens cinema division closed in 1969 , a varifocal lens for the Siemens 2000 was presented.