Sorry about taking so much time to return. I couldn't find a camera which would work properly, but what matters the most is the schematic, I guess. Check the attached file for that.
I got it to work, but there's still some instability source to figure out. I'll try asking for a burrowed oscilloscope at school. I guess that it's either the oscillator stage that goes out of synchronism between its phases at moments, or the amplifier stage that's unbalanced (somehow/somewhat), or the motor is temperamental when using sinewaves which are switched by relay (transients?).
If you spot something that might be causing me trouble, I'd be glad to know. I'll be posting more in here to let you know development until I get these kinks ironed out. In the future I plan to use ganged up potentiometers instead of the 1.2MOhm ones so to control motor speed.
I got it to work, but there's still some instability source to figure out. I'll try asking for a burrowed oscilloscope at school. I guess that it's either the oscillator stage that goes out of synchronism between its phases at moments, or the amplifier stage that's unbalanced (somehow/somewhat), or the motor is temperamental when using sinewaves which are switched by relay (transients?).
If you spot something that might be causing me trouble, I'd be glad to know. I'll be posting more in here to let you know development until I get these kinks ironed out. In the future I plan to use ganged up potentiometers instead of the 1.2MOhm ones so to control motor speed.