My first thought would be a tuned LC filter, resonant around 120 Hz. That would have avoided the noise problem and been far more reliable, and a whole lot cheaper.
When I was designing test equipment for factory floor operation we almost always put a Sola Brabd constant voltage transformer ahead of the controls and instrumantation power input. It was always cheaper than even one service call to fix a machine, and it gave us a reputaion for producing very reliable testing machines. The noise on the waveform on the scope traces looks a bit like it comes froman inverter drive circuit for a medium horsepower motor.
NASA's Orion Flight Software Production Systems Manager Darrel G. Raines joins Planet Analog Editor Steve Taranovich and Embedded.com Editor Max Maxfield to talk about embedded flight software used in Orion Spacecraft, part of NASA's Mars mission. Live radio show and live chat. Get your questions ready.
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