The stability and reliability of "Touch the power control on the chip CAP" ("PX", No. 3/99, p. 35) can be improved by modifying and simplifying the scheme. To improve security, George recommends the resistor R1 (the original numbering scheme) replace with 2 series of 3 MW. Performance is not deteriorating, if in the original diagram, the capacitor C1 and the resistor R3 is short-circuiting, and a protective Zener diode VD1 to get inside the IC there is a corresponding built-in protection. Moving the Zener diode VD2 at a common point VD3/C5, you can achieve proper operation of the rectifier that feeds the IC, and in addition, you receive the possibility is high voltage CDB as VD3 to use a cheap low-voltage KD521 or KD522. As the throttle Etc.1 Yuri recommends a standard DM 0,6 50 µh, and triac - TS-10, paying attention that the Pinout in the last sheet of the magazine "Radio" was incorrect.
Author: Yuri Pencils, Izyum, Kharkov region; Publication: N. Bolshakov, rf.atnn.ru