[sdiy] Re: My friend the CD4069

[studio271]

Er... I read the first reply by someone who had two links to stuff 
but deleted the email before I had a response to the ideas 
presented... The circuit is actually very predictable and steady, 
even if it may seem not to be... Although the ascii schem was 
unreadable in my email, I'll pretend you were able to understand 
it.

Occasionally it will fire when first started up because the cap 
still has energy, but that's not a real problem for me. But is 
very reliable and works right everytime. I tried replacing the 
first inverter with a connection to ground from resistor to the 
next inverter, but when set for short times, that made the output 
very low. I found that using a 1 Meg pot and a 10 uF cap gave a 
good scale between 0 and 9 seconds. I'm guessing that the first 
inverter is needed as the CMOS scale puts the off as between 0V 
and 1.5V (or whereabouts), so it is still putting current out at 
some low voltage.

-Drew 

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