PIC controlled 907 clone

I recently found this on ebay:http://www.ebay.com/itm/1PCS-Solder...180398?hash=item36058a3fee:g:bK8AAOSw0HVWBRRH and had a 12-0-12 transformer lying around. I had a look on the net and found a lot of Arduino PWM controlled versions. I check the original 936D schematic and found it was running off 24V ac using a triac control. I threw in a pic16F628A, moc3021 and a BTA10-600 and got myself a temperature controlled iron. Of course this does not come close to a real 936D (which is discontinued by the way). But instead of buying those not terrible 936D controller clones on ebay I decided to make mine. It has four temperature settings and it regulates at +-3 degrees at tip level. I just moved the controller from breadboard to stripboard to see how stable it is. It can also controlled using an LM358(U1A amp and U1B comparator ) and a pot instead of a pic, some more precautions are necessary to ensure a stable vref for the comparator and feedback compensation but otherwise it works just a s fine. If anyone has built something similar feedback/sharing is welcome. Thanks
 
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