unit was produced for Europools and had three modes of operation; silence
and then a background rumble followed by a big thunder crack, continuous
background rumble and then the thunder crack or just straight into the
thunder crack. This simple kit was produced for the site electrician to
install during the contruction stage of the project and was supplied with
full installation, operation and maintenance instructions. The speakers
shown were for testing only, the actual speakers for the installation
were over double the power of the test speakers!