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How to wire two 555s in parallel?

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Hello.  Newbie here.

I read with interest the article by John Adams about using a 555 as a timer

I am trying to build a controller that would activate a relay in a "non regular" way.  In other words, when I use the astable example John gives, depending on the values used, the circuit will give me "on for 1 sec, off for 2 secs, on for 1 sec, off for 2secs, etc...".  This pattern repeats until power is turned off.  What I would like is to get an irregular pattern such as "on for 1 sec, off for 2.7 sces, on for 0.8 sec, off for 1.4 secs, etc..."  I am not too picky about the actual intervals, as long as it appears more random. 

I was thinking that I could run two 555s with one set for one timing (1 sec on and 2secs off for example) and then second one set for a different timing (1.6 sec On and 1.3 off for example.  I would then take these two outputs and combine them to get a more irregular pattern to trigger my relay.

My question is How do I combine these two outputs without getting overloads or feedbacks or whatever dangerous thing might happen if I simply connect them together before going to the relay.

Or maybe there is a better way to achieve this...

Any help would be greatly appreciated.

Thank you


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