If I did not go the microcontroller PWM route I would use a Johnson counter (twisted ring counter) to directly generate three 120 degree phases. There is a good example here:
http://www.allaboutcircuits.com/vol_4/chpt_12/6.html On Wed, 27 Mar 2013 21:55:32 -0400, Bob Camp <li...@rtty.us> wrote: >Hi > >If three phase is actually needed, I'd suggest something like a cheap PIC with >three PWM outputs. Fairly simple R/C's on the outputs should be plenty good >enough to filter out any crud. Good frequency stability / accurate phase shift >/ cheap. What's not to like . > >Bob > >On Mar 27, 2013, at 9:44 PM, kb0...@juno.com wrote: > >> Bill Ezell; >> >> Your Gyro may require 3 phase, 400 cps, 28 vac, Sine wave. >> >> A simple "Buffered Phase Shift Oscillator" for 400 cps can create the Sine >> Wave. >> https://www.circuitlab.com/circuit/h6v28g/buffered-phase-shift-oscillator/https://www.circuitlab.com/circuit/bakd83/phase-shift-oscillator-ii/You >> will need to add an AGC to the output for frequency stability. >> A "3 Phase Generator" can create the 3 phase >> output.https://www.circuitlab.com/circuit/m4u5nw/3-phase-generator/ Add 3 >> Amplifiers (one for each phase) to reach voltage/power. >> If the Gyro is directional, it will take several hours to stabilize. >> >> Carl _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
