This JAVA interface gives the possibility for working with the radio emission data of radio sources in clusters of galaxies from the Cluster database. ... For this, after loading the document with optical (or radio) data for the requested cluster, click on [ radio spectra (1.2 or 1.1)] in the top line of the document and then choose interface version which is compatible with your Internet-browser. ... For more information about the JDK support in the browsers see Java for browsers . ...