Abstract: The invention relates to an output amplifier for a transmitting tube, having an operating frequency located in the FM- and the VHF- frequency bands. In order to match the output impedance of the preamplifier to the input impedance of the output amplifier the output amplifier includes a broad-band impedance transformer. Mechanical and electrical flexibility is obtained by using an impedance transformer formed from series/parallel arrangements of coaxial cables. The impedance transformer needs little room and nevertheless provides a broadband impedance match.

Abstract: A device comprising a band-pass filter comprising two concentrically arranged coaxial resonator cavities and a coupling capacitor disposed between these resonator cavities, wherein the bandwidth of the filter can be changed by means of a replaceable dielectric body disposed between the plates since the device is separable in two individually associated parts.

Abstract: Amplifier device for the UHF-TV band, assembled from cylindrical conductors which are coaxially arranged with respect to one another and connected to a tetrode. The screen grid is grounded and the control grid is provided with dc voltage connecting terminals required for setting the tetrode.