Mega Transistor Clock – DIY Electronics Kit ------------------------------------------- A large fully discrete digital clock built without integrated circuits. The complete logic is implemented using individual transistors, diodes and other standard electronic components. The clock is designed by me (the seller) in Slovakia, EU. What makes it special --------------------- The clock contains: - 221 transistors - 596 diodes - hundreds of resistors and other discrete components - no microcontroller - no programmable devices - no integrated logic circuits The circuitry itself performs all clock functions. The large PCB makes the finished clock an impressive electronics display as well as a functional clock. Features -------- - Digital and binary time representation - 24-hour time format - Blinking colons - Six red 1.5" display digits - Two push buttons for setting hours and minutes - 32.768 kHz crystal resonator as the time base - Power supply: 5 V, max. 500 mA - PCB dimensions: 48.5 × 37 cm Assembly -------- This is a substantial DIY electronics project intended for people who enjoy soldering and building electronic circuits. All components are through-hole (THT). There are no SMD components to solder. Basic soldering experience is recommended. Although the individual components are straightforward to install, there are many components, so building the clock requires patience and careful work. Typical build time is around 10 hours. No programming, firmware uploading or special programming equipment is required. A detailed manual is available in Slovak and English. It explains the principle of operation and includes both block-level and detailed schematics. The documentation can be downloaded from my website. The download information is also included in the package. Components ---------- All supplied electronic components are new and sourced from reputable electronics distributors. The design uses standard electronic components, so individual parts can also be replaced if necessary. A detailed component list is provided below. NPN transistors (208 pcs) PNP transistors (13 pcs) diodes 1N4148 (596 pcs) electrolytic capacitors 10 μF / 16 V (10 pcs) electrolytic capacitors 1000 μF / 16 V (2 pcs) ceramic capacitors 100 pF (105 pcs) ceramic capacitors 22 pF (2 pcs) ceramic capacitors 100 nF (12 pcs) ceramic capacitors 22 nF (2 pcs) ceramic capacitor 1 nF resistors 150 Ω (66 pcs) resistors 1 kΩ (74 pcs) resistors 100 kΩ (144 pcs) resistors 10 kΩ (165 pcs) resistors 1 MΩ (2 pcs) resistor 10 MΩ resistor 470 kΩ crystal resonator 32.768 kHz display 38.1 mm (1.5 in) red (6 pcs) LED diodes 5 mm red 20 mcd (24 pcs) radial choke 120 μH or similar push buttons 6 mm for PCB (2 pcs) pin header 1x20, pin spacing 2,54 mm 2-lead PCB screw terminal block Available versions ------------------ Green and black PCB is available - please let me know which one you want, after you order (price of both is the same). The kit contains a PCB and the set of all parts required for assembly. A suitable external 5 V power supply is not included as input voltage and plug type varies by country.