The dual-socket, can be inserted in the socket of the lights were not dimming; also make it flicker light, and flicker frequency is adjustable, can be used to set off the indoor atmosphere.
Work

Circuit shown in Figure 1 ( Click here to download the schematic diagram ). When S is open, the circuit is a dimming socket. AC voltage is rectified by the VD1-VD4 into a pulsating DC voltage, added to the VS between the anode and cathode. R1, R2, RP and C1 form RC trigger circuit, when the voltage across C1 rises a certain value, VS conduction, light is lit. When added to the VS pulse between the anode and cathode voltage zero crossing, VS off. Adjustment potentiometer RP C1 charging rate can be changed, thus changing the conduction angle of the VS, so that corresponding changes in voltage across the lamp to achieve the objective of non-dimming. The voltage regulator circuit across the range of the lamp 150-220V, to meet the requirements of the general dimming interior lights. When S is closed, because access to a large capacitor C2, the circuit becomes a flashing circuit. Larger capacity for C2, charging time is longer, when the voltage across C2 when the charge to be even, C2 through the RP, R2 VS control to the very discharge, so that VS conduction, electric light. AC zero crossing, VS block, lights out. C2 Recharge, the formation of ultra-low frequency oscillation cycle, lights will flash light, adjust potentiometer RP, C2 discharge rate can change, that change the lights flicker frequency.
Selection and production of components
Parts list below.

RP is best to use insulated from the shaft rotation, ensure safe use.