The MSTX-1823 is a low cost, highly integrated MMIC-based transmitter, suitable for use in the 18 to 23 GHz microwave radio bands. The transmitter design is based on two MMIC chips from Mimix Broadband, the XU1002 transmitter and the XP1013 medium power amplifier. The transmitter MMIC (XU1002) is designed to operate from 17 to 24 GHz, but the module bandwidth is confined by the printed bandpass filter for LO leakage suppression. The 18 GHz band is cover by low-band (17.7 - 18.7 GHz) and high-band (18.7 - 19.7 GHz) versions of the transmitter. A printed bandpass filter sets these bands, and is the only frequency determining element from 17 - 24 GHz. Features in the transmitter are sub-harmonic mixing, image rejection, and LO buffering. Typical performance of the module includes a typical 22 dBm of output P1dB, 23 dBm of output saturated power, 55 dB of image rejection, 30 dB of gain, and 10 dB RF return loss.