Sawtooth Oscillator

Potis suppose to be wired always with all its three pins. This uneven amplitude is difficult to understand and need some inside understanding of an time discret simulator system like everycircuit. Short, there is a SCR which switches super fast, faster then the simulator can follow, it does not catch this edge at the same moment every time. This cause a different amplitudes. This can be changed with a higher sample rate, but it need an extemly high sampling rate cause SCR do work as fast like a nuclear chain reaction when fired. All SCR or similar fast edges in circuit do make this trouble. Hope this helps.

here a special sim setup, http://everycircuit.com/circuit/6643504170926080