Counting lighting strikes---need to count pulses

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qrper

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Gang…

It’s raining out and I’ve been thinking of doing a project. Right now, it’s a few marks on the paper.

Here’s the jest of the project. I want to make a lighting detector. It would make a great spring project!

Using an am radio tuned to the low end of the band, the audio output will be converted over to dc and a small amount of capaitance added to smooth out the dc. From here, the resulting dc will be feed to a voltage comparator An adjustable reference voltage will set the trip point of the comparator. When the radio detects a lighting strike, the audio will peak and the resulting voltage will cause the comparator to change states, sending out a low to high transition.

So, I need something to count these pulses. Lets say I would like to count ten lighting strikes, have the counter output a logic level from low to high ( I can invert if need be)

After the first lighting strike, a timer will start and after a minute or so, the timer runs out and resets the counter. This will prevent false tripping as I only want to know about lighting strikes that happen within my timer range.

If the lighting is coming fast enough the counter (say 10 lighting strikes or the comparator will toggle from low to high for ten times) will flip and its output will light a light, launch missiles or blow a horn.

Any ideas on how to count my pulses? I was thinking maybe a 4017, but I only need a few counts.
 
the 4017 is the easy way IMHO

unless you want a 7 segment display.
for a 3 digit counter = 1- 14553 + 4511
a one digit counter = 1/2 of a 4518 + 4511
or
7490 + 7475 + 7447

IMHO the 4017 is the best bet. add a schmith trigger or a 4011 to clean up the input pulse.
the 4017 can be connected to count to N (N =1-10)
 
thanks for the idea..

no, there's no need for a display, I just want to count pulses.. and then after N count, do something like drive a alarm or what not.

you think cleaning up the pulses before the 4017 would be a good idea?
 
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