Nite Rider Lights
- Paul Hill
- hillpa@ntlworld.com
- 25.316 Views
- moderate
- Non tested
Description
The circuit is drawn with PCB 123 which you can download for free from http://www.pcb123.com
As a keen cyclist I am always looking for ways to be seen at night. I wanted something that was a novelty and would catch the motorists eye. So looking around at my fellow cyclists rear lights, I came up with the idea of ‘NITE-RIDER’. NINE extra bright LED’s running from left to right and right to left continuously. It could be constructed with red LEDs for use on the rear of the bike or white LED’s for an extra eye catcher on the front of the bike.
All IC’s are CMOS devices so that a 9V PP3 battery can be used, and the current drawn is very low so that it will last as long as possible.
Parts
Part | Quantity | Value |
IC4 | 1 | 555 timer |
IC1 | 1 | 4027 flip flop |
IC2,IC3 | 2 | 4017 Decade Counter |
IC5, IC6, IC7 | 3 | 4071 OR gate |
R3 | 1 | 470 Ohm resistor 1/4 watt |
R1, R2 | 2 | 10K resistors 1/4 watt |
C1 | 1 | 6.8UF Capasitor 16V |
LED1-LED9 | 9 | Super brght LED’s |
Battery | 1 | 9V PP3 Battery |
SW1 | 1 | single pole switch |
How it works
IC4, C1, R1 and R2 are used for the clock pulse which is fed to both the counters IC2 and IC3 Pin 14.
IC1 is a Flip Flop and is used as a switch to enable ether IC2 or IC3 at pin 13.
IC7a detects when ether IC2 or IC3 has reached Q9 of the counter pin 11.
IC5, IC6 and IC7a protects the outputs of the counters IC2 and IC3 using OR gates which is then fed to the Anodes of the LED’s 1 to 9.
Nice post
Good circuit – is there a pic of the finished item? Some suggestions: There should be a cap across supply (100microF or so). Better to use Cmos 555. Better still, there are 2 unused gates in IC7, so use 4001 (quad NOR) for IC5,6 and 7, use IC7a (and all of IC5 and 6) to drive LEDs (referenced to V+ instead – gates should drive LED cathodes with common anodes’ R to V+), use IC7b to make an oscillator (100K+100n?), then use IC7c and IC7d wired as OR (i.e. IC7d inverts IC7c out). In any event, all unused inputs should be tied to either supply rail (including the 4027).
Thanks for the comments and feedback. This is a rather old project, but someone may want to rebuild.