Abstract: A modulation amplifier includes a signal converter, a summator and a plurality of high frequency stages (3.sub.1-m or 4.sub.1-n). The high frequency stages (3.sub.1-m) are driven by equiphased control signals (s.sub.1-m); the high frequency stages (4.sub.1-n) are driven by control signals (t.sub.1-n) of different phase .PHI..sub.1-n. The high frequency stages (3.sub.1-m or 4.sub.1-n) can be selected in an arbitrary manner by the control signals (s.sub.1-m or t.sub.1-n). The summator adds the high frequency output signals (x.sub.1-m or y.sub.1-n) of the high frequency stages (3.sub.1-m or 4.sub.1-n). The output signal can be conveyed, for example, to a low pass and a subsequent load. The phases (.PHI..sub.1-n) of the output signals (y.sub.1-n) of the high frequency stages (4.sub.1-n) correspond to those of the control signals (t.sub.1-m). So many high frequency stages (3.sub.

Abstract: In an amplitude-modulated broadcast transmitter for various types of modulation, particularly DSB (double sideband), SSB (single sideband) and ISB (independent sideband), of at least one AF signal to be transmitted, the sum and the difference is formed from the two input channels (7a, 7b). Either the sum or the difference is subjected to a Hilbert transformation in a Hilbert transformer (12). From these signals, an amplitude signal is formed in an amplitude processor (22) and a phase signal is formed in a cyclic sampler (21) and a phase conditioner (23). The amplitude signal is used for anode modulating the transmitting tube (5) and the phase signal is used for grid modulating the transmitting tube. The amplitude-modulated broadcast transmitter for various types of modulation has the advantage that the three types of modulation ISB, DSB and SSB can be set by allocating the AF signals to be transmitted to the two input channels (7a, 7b).