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Materials
Gerber file
CAM/CAD data for the PCB referred to in this article is available as a Gerber file. Elektor GREEN and GOLD members can exclusively download these files for free as part of their membership. Gerber files allow a PCB to be produced on an appropriate device available locally, or through an online PCB manufacturing service.
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Component list
R1,R3,R5,R7,R9,R11 = 220
R2,R6,R10 = 1k
R4,R8,R12,R13 = 47k
R14 = 330
R15-R22 = 10k
R23,R24,R25 = 22k
R26 = 1k8
Capacitors:
C1,C11 = 100nF (C1 5mm lead pitch)
C2,C5 = 220µF 16V radial
C3 = 22nF, lead pitch 5mm
C4,C7-C10 = 4µF7 63V radial
C6 = 220µF 25V radial
Inductors:
L1 = 47µH
Semiconductors:
D1-D22 = 1N4148
D23 = LED, low current
D24 = 1N4007
T1-T3 = BC212B
T4 = BC549C or BC550C
T5-T10 = BC237B
IC1 = PIC16F628-20/P, programmed, order code 050039-41*
IC2 = MAX232
IC3,IC4,IC5 = IL250 (H11AA4)
IC6 = 78L05
IC7 = 7809
Miscellaneous:
JP1-JP16 = 2-way pinheader and 8 jumpers
K1-K4 = RJ11 PCB mount socket
K5 = 9-way sub-D socket (female), angled pins, PCB mount
X1 = not fitted, see text
RE1,RE2,RE3 = 12V PCB relay, bistable, two energising solenoids 2 x 400?, two changeover contacts, e.g., DS2E-ML2-12VJ Panasonic (Schuricht # 407220; www.schuricht.de)
2 wire links
LCM First Server 1.1 + PIC source & hex code files 050039-81
PCB, ref. 050039-1 from The PCBShop
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