Parts for the New Laser Gate


All the parts can be obtained from Digikey and Conrad.

From "DigiKey"

Item Number/Description Price (Dec 2011)
PIC16F690-I/P-ND
(IC PIC MCU flash 20DIP) $2.44
X909-ND
ZIT-20.00MX ceramic resonator $0.60
609-3291-ND
Conn Header 6POS $0.44
480-1952-ND
Phototransistor NPN T1 (SDP8405-003) $2.10
A404AE-ND
20 Pin Solder Tail Dip Socket $1.53
768-1028-ND
Cable USB to TTL Serial Conv $20.00

We note that it is very important to have the correct IR detector. The one listed above, SDP8405-003 made by Honeywell, works well. The detector must have the following resistance properties: high resistance without laser (above 2000 Ohms), and a low resistance when the laser is shining on it (less than 500 Ohms). This change in resistance acts as a TTL switch on pin 11. I believe the pin goes from low to high at around 1000 Ohms.

From "Conrad"

Item Number/Description Price (Aug 2013)
526819-62
Steckplatine EIC-801 € 8,43
524530-62
Verdrahtungs-Set EIC-J-S Steckbruecken-Set € 6,84
165193-62
Batteriehalter BH2AAW Kunststoff Schwarz € 3,19
184560-62
LED 3 mm RTL 934 HD Rot 45deg € 0,07
816476-62
Lasermodule Red 1 mW Laserfuchs LFD650-1-12 € 7,50
405175-62
Resistor: 220 Ohms, 0.5 W € 0,09

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