Craft Drill Controller

for semi-automated PCB drilling — and more

Published in issue 372, December 2007

Resistors
R1,R28,R29 = 100
R2,R6,R9,R10,R15,R18,R21,R24 = 1k
R3 = 15Ω 2W
R4,R30 = 2kΩ2
R5,R12,R13 = 15k
R7,R8,R11,R16,R17,R22,R23 = 4kΩ7
R14,R19 = 2kΩ7
R20, R25 = 10k
R26,R27 = 100k
P1,P2 = 5kΩ linear-law potentiometer
P3,P4 = 10kΩ linear-law potentiometer
P5 = 50kΩ linear-law stereo potentiometer
Capacitors
C1 = 100nF
C2 = 470nF
C3,C4,C7,C8 = 220μF 25V radial electrolytic
C5,C6 = 220nF
C9,C10 = 22nF
Semiconductors
D1,D6,D7,D8,D9,D10,D11 = 1N4148
D2,D3,D4,D5,D12,D13 = LED, low current
T1,T4 = BS170
T2,T3,T8,T9,T10,T11= BC560C
T5,T6,T14,T15,T16,T17= BC550C
T7 = TIP122
T12,T13 = BS250P (watch suffix P)
IC1 = L7805CV
Miscellaneous
S1 = on/off switch, 1 make contact
S2 = on/off switch, 1 make contact
S3 = footswitch, on/off, 1 make contact, see text.
S4 = single-pole changeover switch
S5 = single-pole changeover switch
PCB, ref. 060291-I from ThePCBShop; free artwork download # 060291-1.zip
Front & rear panel artwork files