Abstract: A modular solid-state radar transmitter apparatus for producing waveforms whose amplitude may be varied over time. The transmitter achieves pulse modulation on either an intrapulse or pulse to pulse basis, while at the same time reducing stress on individual solid-state modules. Intrapulse modulation and pulse to pulse modulation can be produced with the disclosed modular solid-state transmitter because the number of modules and the sequence in which they are activated is selectable. These selections provide the various desired levels of transmitted power and thus effectively achieve modulation. In order to achieve this intrapulse modulation, a variable combiner is introduced whose coupling factor is coordinated with the module activations. In one embodiment, variable combining is accomplished by the use of RF switching logic for combining pairs of signals in parallel. In this case, RF switches are programmed to act as a conventional combiner when all modules are active.