LED Flassher for Bicycle indicators with auto cancel.

[Johnny 5C]

I'd like to build a simple indicator system for my bike. I was thinking along the lines of a single pole double throw momentary toggle switch, (on) off (on), driving a set of LED placed on the handlebar ends. If the toggle is clicked left (and back to off) the left LED's flash 5-7 times in 0.5hz cycles, for instance. The same for a right toggle. I have experience with microcontrollers, but I would like to make this as simple as possible, and hence, cheap, with discrete components, 555's etc.

The (on) off (on) switch has to stay, because i have already made a fixing for it on the handlebars, which works!
Cheers in advance.

Johnny

 

[Dragon Tamer]

If you want simple and cheap the use four 555 timers. Two for monostable for the 2.5 -3.5 seconds that they should be on, having one for each side. The monostable will drive another 555 in stable operation with a 0.5Hz output signal. It doesn't get that much cheaper than that.

 

[Johnny 5C]

Dragon,

Thanks. I could use two 556's.
So, the monostable produces a 5-6 second pulse, which triggers the second stable stage to flash at 0.5hz. Im sure i can find examples of the monostable and stable wiring on the net.

Cheers.

 

[Dragon Tamer]

The monostable 555 simply allows the astable to run freely as long as it's output is high. If you need anymore help, it is being discussed in this thread: https://www.electro-tech-online.com/threads/small-timer-project.123599/