Aerospace research and more with microphone technology from Microtech Gefell

Since 2011, the United Nations annually celebrates the International Day of Human Space Flight on 12 April.

In its resolution A/RES/65/271 the General Assembly declared 12 April as the International Day of Human Space Flight “…to celebrate each year at the international level the beginning of the space era for mankind, reaffirming the important contribution of space science and technology in achieving sustainable development goals and increasing the well-being of States and peoples, as well as ensuring the realization of their aspiration to maintain outer space for peaceful purposes.”

44 years ago, the first German saw the Earth from space. On board – microphone technology from Gefell.

26 August 1978 the Soyuz 31 rocket started at the space port of Baikonour. One of the crew members of the „Interkosmos“ mission was Sigmund Jähn, the first and only Pilot-Cosmonaut of the GDR (Wikipedia/Bundesarchiv,Bild183-T0709-148/Peter Koard/CC-BY-SA,CCBY-SA 3.0).

The Interkosmos programme offered the opportunity to carry out important experiments in basic research, including acoustic measurements with technology from Gefell.

With the experiment „Audio“, it was attempted to record possible changes of hearing within the frequency range 250-8000 Hz, which are caused by the space flight factor Weightlessness.
Under the influence of the redistribution of blood and other liquid substances in the human body, the functional condition of the sense of hearing changes. Substantial changes of the
perceptions of sound volume may occur. i.e. all noises are heard louder.
Using the precision impulse sound level meter 00024 of the VEB RFT Messelektronik „Otto Schön“ Dresden, equipped with the 1/2 inch measurement microphone preamplifier
MV 202 and the measurement microphone capsule MK 202 of the company Georg Neumann Gefell noise measurements were performed in the orbital station Salut 6 at different locations of the crew members.

The measured values of 60-70 dBA near the ground were anything but ideal and demonstrated a health-damaging noise exposure in the space station.

Even later, back on earth, astronauts liked to use proven microphone technology from Gefell. For example, during the 15th Space Days in Morgenröthe-Rautenkranz.

The cosmonauts – Dr Sigmund Jähn, Maxim Wiktorowitsch Surajew and astronauts – Dr Alexander Gerst, Reinhold Ewald, Dr Gerhard Thiele again used a special microphone from Gefell in their lectures – the cardioid plane microphone KEM 975.

Until today acoustic measurement technology from Gefell supports the development of technology for aerospace research.

For example, it is currently planned to use the new digital measuring system MV 240 in the development of a special acoustic measuring device for the International Space Station ISS.

The future of  acoustic measurements – MV 240 digital- 1/2“ Microphone Preamplifier with integrated ADC

The innovative MV 240 digital is the first an all-in-one USB solution, which differs in every respect from all commercially available analog-digital solutions in terms of design, functionality  and quality.

The user is absolutely independent of special manufacturer software, possibility of using commercially available measurement software, the system is fully compatible with all common operating systems, such as Windows® (XP, Vista, 7, 8, 8.1, 10), Linux, Mac OS®, ioS®),

With the specially developed high-end, low noise capsule and the new, integrated electronics the MV 240 expands the circle of potential users considerably.

Exactness and simplified operation make it possible to optimize existing and find new, cost-saving applications (e.g. R&D, industry, environment,  occupational health and safety, Study or training sector).

Existing disadvantages could be overcome, e.g:

• time-consuming and personnel-intensive installation and operation,
• Errors due to complicated coordination of several electronic and software components,
• handling the electrical voltage as a coupler by the user,
• Measurable / audible USB artifacts, 
• Insufficient sensitivity or limited frequency range, etc.

The MV 240 thus offers the possibility of solving all disadvantages of previous AD solutions with just one device, replacing 2 analogue microphones, 2 analogue front end channels and part of the digital signal processing in a cost-saving way.