Help required please

Hi to everyone.

I wonder if anyone can help me with what must be a simple answer but can't find any reference or real help on the web?

I'm looking to build an American Don't Walk / Walk pedestrian crossing light. I am looking for the Dont Walk sign to light up for ten seconds and then change to the walk sign for ten seconds. That's about it but I can't find any reference to building a circuit that has this amount of delay time between the alternating led lights. I brought the build it yourself alternating kit but the max amount time each lights up is only about 5 seconds. I'm not the best soldering so any advice on how I can do this would be greatly appreciated.

Many thanks.

Welcome to ETO!

Csteve2409 said:

I brought the build it yourself alternating kit but the max amount time each lights up is only about 5 seconds.

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Can you post a schematic of the circuit you used?

Hello, many thanks for your reply.

This is the copy of the details you get with the Vellemans kit.

Many thanks.

I found this: https://www.automation24.com/multif...reviewPriceListId=1&refID=adwords_shopping_US

it's fairly cheap and has a wide supply voltage, but >=12V DC.

The DIN rail and mounts will cost a few extra dollars. https://www.winford.com/products/dinr.php

Timing >seconds is "harder" because the product of R&C (seconds)using practical resistors and capacitors don't cut it.
10 M ohms and 2 uF. So, you either have to use an oscillator and counter or micro-processor

The Velleman's circuit is not ideal for long time delays, but you could try either :
1) replacing R3 and R4 with 270kΩ resistors, or
2) replacing C1 and C2 with 33uF electrolytic capacitors.

Thank you so much.

It does not have to be exactly 10 seconds, just around that sort of time delay between each LED lighting. In fact it could be longer. I had looked at a 555 chip (is that correct?) but truthfully I'm a bit lost when it comes to these things.