Low-cost 1 Watt RF power amplifier (in progress)

Low-cost, 800mA RF power amplifier used for tabletop MRI scanners to drive small solenoid coils (~1cm diameter NMR sample tubes). This board uses the Motorola MHW592 RF amplifier module, which is obsolete, but available on eBay. The board runs on 24 Volts and includes a linear regulator and blanking circuit controlled by a gating signal from the spectrometer. The blanking cuts power to the RFPA quickly (for instance to eliminate unwanted RF noise during signal readout). There is an optional low-power first gain stage that can be bypassed with a jumper wire if it is not needed.

Datasheet for MHW592: https://datasheetspdf.com/pdf-file/1114767/Motorola/MHW592/1 The MHW592 provides 35dB of gain with a 1dB compression point of 900mW.

Click here to download EAGLE board files (layout and schematic), GERBER files, and Bill of Materials.