Scientech Technologies Pvt. Ltd. Offers Single Phase Controlled Rectifier with Cosine Firing Scheme, ST2709. Scientech Technologies Pvt. Ltd. Is an ISO 9001:2000 certified company and is the manufacturer of test and measurement instruments. The Single Phase Controlled Rectifier is a compact and ready to use power electronics experiment board having Cosine firing circuit on board. It helps the students to know generating of firing pulses for single phase converter with this cosine firing scheme. This Single Phase Controlled Rectifier with Cosine Firing Scheme comes with the following key features: