U1 & U2 - NE555 timer
Q1 - 5A, 400 PIV triac (BT136)
D1-D3 - IN4001 rectifier diodes
D4-D6 - IN4148 switching diodes
R1 - 5.6K
R2 -2.2K
R3 -470 ohms
R4 - 100K linear potentiometer with plastic shaft
(all resistors ¼ watt, 5% tolerance)
C1 - 1000mfd, 12V
C2 - 1mfd, 12V
C3,C4 - 0.1mfd,50V ceramic
T1 - 220V primary 6V-0-6V secondary, 150ma
F1 - 5-amp fuse
(You will have to connect the AC line to T1 primary. I have not shown that)