Table of Contents

EMC-Test results

EMC is the abbreviation for Electro Magnetic Compatibility. It does describe the capability of electronic devices to co-exist in an electronic environment. In general one can distinguish between two interference phenomena:

Inside a glider, there is various electronic equipment, which can create unwanted electromagnetic noise on the one hand side, and equipment, which is very sensitive to interference on the other hand side. Especially the radio is subject to both, being disturbed by other electronic instrumentation (Computers, Cellphones, DC-DC-converters…) while listening, and creating very strong signals while transmitting. If we consider the unwanted emissions created by a device, there are two possible ways for emissions:

The closer the spearation of devices is, the more critical EMC issues are. In a narrow cockpit the need for well behaved equipment is obvious to ensure proper function of all devices in use. Therefore we tested the OpenVario for compliance to the most important EMC standards and present the results here.

Frequency Ranges to be protected

The following freguency ranges are used in airborne equipment and need to be protected against unwanted disturbances:

Frequency Range in MHz Service Description Nominal Value Measured Remarks
117.975–137 VHF AM Radio dBµV/m x Very sensitive to disturbance due to AM https://en.wikipedia.org/wiki/Airband#Spectrum_usage
320-340 ILS dBµV/m x Not really important for gliders…
868 FLARM dBµV/m x RX case only
1227.60 L2GPS dBµV/m x L2GPS https://en.wikipedia.org/wiki/GPS_signals#Frequencies_used_by_GPS
1575.42 L1GPS dBµV/m x L1GPS
960-1164 GPS dBµV/m x DO-160
1559-1610 GPS dBµV/m x DO-160
1610-1680 GPS dBµV/m x DO-160
5020-5100 ? dBµV/m x DO-160

EMC Standards for Airborne Equipment

There are many EMC-standards in general, but for civil aviation the most often applied standard is the RTCA/DO-160F. Further there is an important military standard called MIL STD 461F, although not applicable to the OpenVario, it gives valuable information about the EMC characteristics.

Conducted RF Emissions

DO-160F section 21.4

Coming soon…

Radiated RF Emissions

DO-160F section 21.5

Coming soon…